37 files changed, 1682 insertions, 1328 deletions

diff --git a/Xamarin.PropertyEditing.Mac/Controls/BasePointEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/BasePointEditorControl.cs
index b438f2c..287a92f 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/BasePointEditorControl.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/BasePointEditorControl.cs
@@ -15,7 +15,7 @@ namespace Xamarin.PropertyEditing.Mac
 		internal NumericSpinEditor<T> YEditor { get; set; }
 
 		public override NSView FirstKeyView => XEditor;
-		public override NSView LastKeyView => YEditor;
+		public override NSView LastKeyView => YEditor.DecrementButton;
 
 		public BasePointEditorControl ()
 		{
diff --git a/Xamarin.PropertyEditing.Mac/Controls/BaseRectangleEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/BaseRectangleEditorControl.cs
index 5cdd872..1c57694 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/BaseRectangleEditorControl.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/BaseRectangleEditorControl.cs
@@ -21,7 +21,7 @@ namespace Xamarin.PropertyEditing.Mac
 		protected NumericSpinEditor<T> HeightEditor { get; set; }
 
 		public override NSView FirstKeyView => XEditor;
-		public override NSView LastKeyView => HeightEditor;
+		public override NSView LastKeyView => HeightEditor.DecrementButton;
 
 		public BaseRectangleEditorControl ()
 		{
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericSpinEditor.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericSpinEditor.cs
index edb17f5..1aabaa0 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericSpinEditor.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericSpinEditor.cs
@@ -2,6 +2,8 @@
 using AppKit;
 using CoreGraphics;
 using Foundation;
+using Xamarin.PropertyEditing.Drawing;
+using Xamarin.PropertyEditing.Themes;
 
 namespace Xamarin.PropertyEditing.Mac
 {
@@ -12,8 +14,21 @@ namespace Xamarin.PropertyEditing.Mac
 	internal class NumericSpinEditor : NSView, INSAccessibilityGroup
 	{
 		NumericTextField numericEditor;
-		NSStepper stepper;
-		bool editing;
+		public NumericTextField NumericEditor {
+			get { return numericEditor; }
+		}
+
+		UpSpinnerButton incrementButton;
+		public UpSpinnerButton IncrementButton {
+			get { return incrementButton; }
+		}
+
+		DownSpinnerButton decrementButton;
+		public DownSpinnerButton DecrementButton {
+			get { return decrementButton; }
+		}
+
+		protected bool editing;
 
 		public event EventHandler ValueChanged;
 		public event EventHandler EditingEnded;
@@ -31,28 +46,16 @@ namespace Xamarin.PropertyEditing.Mac
 			set { ((NSTextFieldCell)numericEditor.Cell).PlaceholderString = value; }
 		}
 
-		NSStepper Stepper {
-			get { return stepper; }
-		}
-
-		public NSTextField TextField {
-			get { return numericEditor; }
-		}
-
 		public override CGSize IntrinsicContentSize {
 			get {
-				var baseSize = stepper.IntrinsicContentSize;
-				return new CGSize (baseSize.Width + 40, baseSize.Height);
+				var baseSize = numericEditor.IntrinsicContentSize;
+				return new CGSize (baseSize.Width + 20, baseSize.Height);
 			}
 		}
 
 		public NSColor BackgroundColor {
-			get {
-				return numericEditor.BackgroundColor;
-			}
-			set {
-				numericEditor.BackgroundColor = value;
-			}
+			get { return numericEditor.BackgroundColor; }
+			set { numericEditor.BackgroundColor = value; }
 		}
 
 		public override nfloat BaselineOffsetFromBottom {
@@ -66,7 +69,7 @@ namespace Xamarin.PropertyEditing.Mac
 
 
 		public double Value {
-			get { return stepper.DoubleValue; }
+			get { return numericEditor.DoubleValue; }
 			set { SetValue (value); }
 		}
 
@@ -76,47 +79,38 @@ namespace Xamarin.PropertyEditing.Mac
 			set { SetValue (value); }
 		}
 
-		public bool Wrap {
-			get { return stepper.ValueWraps; }
-			set { stepper.ValueWraps = value; }
-		}
-
 		public double MinimumValue {
-			get { return stepper.MinValue; }
+			get { return formatter.Minimum.DoubleValue; }
 			set {
-				stepper.MinValue = value;
 				formatter.Minimum = new NSNumber (value);
 			}
 		}
 
 		public double MaximumValue {
-			get { return stepper.MaxValue; }
+			get { return formatter.Maximum.DoubleValue; }
 			set {
-				stepper.MaxValue = value;
 				formatter.Maximum = new NSNumber (value);
 			}
 		}
 
+		double incrementValue = 1.0f;
 		public double IncrementValue {
-			get { return stepper.Increment; }
-			set { stepper.Increment = value; }
+			get { return incrementValue; }
+			set { incrementValue = value; }
 		}
 
 		public bool Enabled {
-			get {
-				return numericEditor.Enabled;
-			}
+			get { return numericEditor.Enabled; }
 			set {
 				numericEditor.Enabled = value;
-				stepper.Enabled = value;
+				incrementButton.Enabled = value;
+				decrementButton.Enabled = value;
 			}
 		}
 
 		NSNumberFormatter formatter;
 		public NSNumberFormatter Formatter {
-			get {
-				return formatter;
-			}
+			get { return formatter; }
 			set {
 				formatter = value;
 				numericEditor.Formatter = formatter;
@@ -124,32 +118,31 @@ namespace Xamarin.PropertyEditing.Mac
 		}
 
 		public bool IsIndeterminate {
-			get {
-				return !string.IsNullOrEmpty (numericEditor.StringValue);
-			}
+			get { return !string.IsNullOrEmpty (numericEditor.StringValue); }
 			set {
 				if (value)
 					numericEditor.StringValue = string.Empty;
-				else
-					numericEditor.DoubleValue = stepper.DoubleValue;
 			}
 		}
 
 		public bool Editable {
-			get {
-				return numericEditor.Editable;
-			}
+			get { return numericEditor.Editable; }
 			set {
 				numericEditor.Editable = value;
-				stepper.Enabled = value;
+				incrementButton.Enabled = value;
+				decrementButton.Enabled = value;
 			}
 		}
 
 		public NSNumberFormatterStyle NumberStyle {
 			get { return formatter.NumberStyle; }
-			set {
-				formatter.NumberStyle = value;
-			}
+			set { formatter.NumberStyle = value; }
+		}
+
+		public bool AllowRatios
+		{
+			get { return numericEditor.AllowRatios; }
+			set { numericEditor.AllowRatios = value; }
 		}
 
 		protected virtual void OnConfigureNumericTextField ()
@@ -157,6 +150,12 @@ namespace Xamarin.PropertyEditing.Mac
 			numericEditor.Formatter = formatter;
 		}
 
+		public bool AllowNegativeValues
+		{
+			get { return numericEditor.AllowNegativeValues; }
+			set { numericEditor.AllowNegativeValues = value; }
+		}
+
 		public virtual void Reset ()
 		{
 		}
@@ -166,99 +165,110 @@ namespace Xamarin.PropertyEditing.Mac
 			TranslatesAutoresizingMaskIntoConstraints = false;
 			var controlSize = NSControlSize.Small;
 
-			stepper = new NSStepper {
-				TranslatesAutoresizingMaskIntoConstraints = false,
-				ValueWraps = false,
-				ControlSize = controlSize,
-			};
+			incrementButton = new UpSpinnerButton ();
+
+			decrementButton = new DownSpinnerButton ();
 
 			formatter = new NSNumberFormatter {
 				FormatterBehavior = NSNumberFormatterBehavior.Version_10_4,
 				Locale = NSLocale.CurrentLocale,
 				MaximumFractionDigits = 15,
+				Maximum = double.MaxValue,
+				Minimum = double.MinValue,
 				NumberStyle = NSNumberFormatterStyle.Decimal,
 				UsesGroupingSeparator = false,
 			};
 
 			numericEditor = new NumericTextField {
 				Alignment = NSTextAlignment.Right,
-				Formatter = formatter,
 				TranslatesAutoresizingMaskIntoConstraints = false,
 				Font = NSFont.FromFontName (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultFontSize),
 				ControlSize = controlSize,
 			};
 
-			stepper.Activated += (s, e) => {
-				OnStepperActivated (s, e);
-			};
+			incrementButton.OnMouseLeftDown += (sender, e) => { IncrementNumericValue (); };
+			decrementButton.OnMouseLeftDown += (sender, e) => { DecrementNumericValue (); };
 
-			numericEditor.KeyArrowUp += (sender, e) => { IncrementNumericValue (); };
-			numericEditor.KeyArrowDown += (sender, e) => { DecrementNumericValue (); };
+			numericEditor.KeyArrowUp += (sender, e) => { IncrementNumericValue (e); };
+			numericEditor.KeyArrowDown += (sender, e) => { DecrementNumericValue (e); };
 
 			numericEditor.ValidatedEditingEnded += (s, e) => {
 				OnEditingEnded (s, e);
 			};
 
-			AddSubview (stepper);
 			AddSubview (numericEditor);
+			AddSubview (incrementButton);
+			AddSubview (decrementButton);
 
 			this.DoConstraints (new[] {
 				numericEditor.ConstraintTo (this, (n, c) => n.Width == c.Width - 16),
-				numericEditor.ConstraintTo (this, (n, c) => n.Height == 19),
-				stepper.ConstraintTo (numericEditor, (s, n) => s.Left == n.Right + 4),
-				stepper.ConstraintTo (numericEditor, (s, n) => s.Top == n.Top),
+				numericEditor.ConstraintTo (this, (n, c) => n.Height == PropertyEditorControl.DefaultControlHeight - 3),
+				incrementButton.ConstraintTo (numericEditor, (s, n) => s.Left == n.Right + 5),
+				incrementButton.ConstraintTo (numericEditor, (s, n) => s.Top == n.Top + 1),
+				incrementButton.ConstraintTo (numericEditor, (s, n) => s.Width == 9),
+				incrementButton.ConstraintTo (numericEditor, (s, n) => s.Height == 9),
+				decrementButton.ConstraintTo (numericEditor, (s, n) => s.Left == n.Right + 5),
+				decrementButton.ConstraintTo (numericEditor, (s, n) => s.Top == n.Top + 10),
+				decrementButton.ConstraintTo (numericEditor, (s, n) => s.Width == 9),
+				decrementButton.ConstraintTo (numericEditor, (s, n) => s.Height == 9),
 			});
+
+			PropertyEditorPanel.ThemeManager.ThemeChanged += ThemeManager_ThemeChanged;
+
+			UpdateTheme ();
 		}
 
-		protected virtual void SetStepperActivated ()
+		protected override void Dispose (bool disposing)
 		{
-			SetValue (stepper.DoubleValue);
+			if (disposing) {
+				PropertyEditorPanel.ThemeManager.ThemeChanged -= ThemeManager_ThemeChanged;
+			}
 		}
 
-		protected void OnStepperActivated (object sender, EventArgs e)
+		void ThemeManager_ThemeChanged (object sender, EventArgs e)
 		{
-			if (!editing) {
-				editing = true;
-				SetStepperActivated ();
-				if (ValueChanged != null)
-					ValueChanged (this, EventArgs.Empty);
-				editing = false;
-			}
+			UpdateTheme ();
 		}
 
-		protected void OnValueChanged (object sender, EventArgs e)
+		protected void UpdateTheme ()
 		{
-			if (!editing) {
-				editing = true;
-				SetValue (numericEditor.StringValue);
-				if (ValueChanged != null)
-					ValueChanged (this, EventArgs.Empty);
-				editing = false;
+			this.Appearance = PropertyEditorPanel.ThemeManager.CurrentAppearance;
+
+			// Skin the inc/dec buttons until we support theming files
+			switch (PropertyEditorPanel.ThemeManager.Theme) {
+				case PropertyEditorTheme.Dark:
+					incrementButton.Image = NSImage.ImageNamed ("stepper-up"); // TODO path to proper image
+					decrementButton.Image = NSImage.ImageNamed ("stepper-down"); // TODO path to proper image
+					break;
+
+				case PropertyEditorTheme.Light:
+					incrementButton.Image = NSImage.ImageNamed ("stepper-up"); // TODO path to proper image
+					decrementButton.Image = NSImage.ImageNamed ("stepper-down"); // TODO path to proper image
+					break;
+
+				case PropertyEditorTheme.None:
+					incrementButton.Image = NSImage.ImageNamed ("stepper-up"); // TODO path to proper image
+					decrementButton.Image = NSImage.ImageNamed ("stepper-down"); // TODO path to proper image
+					break;
 			}
+
 		}
 
-		protected void OnEditingEnded (object sender, EventArgs e)
+		virtual protected void OnEditingEnded (object sender, EventArgs e)
 		{
 			if (!editing) {
 				editing = true;
 				SetValue (numericEditor.StringValue);
-				if (EditingEnded != null)
-					EditingEnded (this, EventArgs.Empty);
-				if (ValueChanged != null)
-					ValueChanged (this, EventArgs.Empty);
+				EditingEnded?.Invoke (this, EventArgs.Empty);
 				editing = false;
 			}
 		}
 
 		void SetValue (string value)
 		{
-			//Regulates maximun and minium out of range
-			if (!string.IsNullOrEmpty (value)) {
-				stepper.DoubleValue = CoerceValue (FieldValidation.FixInitialValue (value, Value.ToEditorString ()).ToEditorDouble ());
-				numericEditor.StringValue = FieldValidation.RoundDoubleValue (stepper.DoubleValue.ToEditorString (), NumericMode == ValidationType.Decimal ? FieldValidation.DefaultXcodeMaxRoundDigits : 0);
-			} else {
-				stepper.StringValue = value;
+			if (numericEditor.StringValue != value) {
 				numericEditor.StringValue = value;
+				NotifyingValueChanged (EventArgs.Empty);
 			}
 		}
 
@@ -267,21 +277,40 @@ namespace Xamarin.PropertyEditing.Mac
 			SetValue (value.ToString ());
 		}
 
-		protected double CoerceValue (double val)
+		protected void NotifyingValueChanged (EventArgs eventArgs)
+		{
+			ValueChanged?.Invoke (this, eventArgs);
+		}
+
+		public void IncrementNumericValue (bool shiftPressed = false)
+		{
+			if (!editing) {
+				editing = true;
+				SetIncrementOrDecrementValue (shiftPressed ? 10 * incrementValue : incrementValue);
+				editing = false;
+			}
+		}
+
+		public void DecrementNumericValue (bool shiftPressed = false)
 		{
-			return FieldValidation.CoerceValue (val, MinimumValue, MaximumValue);
+			if (!editing) {
+				editing = true;
+				SetIncrementOrDecrementValue (-(shiftPressed ? 10 * incrementValue : incrementValue));
+				editing = false;
+			}
 		}
 
-		public void IncrementNumericValue ()
+		virtual protected void SetIncrementOrDecrementValue (double incDevValue)
 		{
-			SetValue (stepper.DoubleValue + IncrementValue);
-			OnStepperActivated (stepper, EventArgs.Empty);
+			// Constrain our value to our Min/Max before we set it
+			var newValue = Clamp (numericEditor.DoubleValue + incDevValue);
+
+			SetValue (newValue);
 		}
 
-		public void DecrementNumericValue ()
+		public double Clamp (double value)
 		{
-			SetValue (stepper.DoubleValue - IncrementValue);
-			OnStepperActivated (stepper, EventArgs.Empty);
+			return (double)Decimal.Round ((decimal)(value < MinimumValue ? MinimumValue : value > MaximumValue ? MaximumValue : value), Digits);
 		}
 	}
 }
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericTextField.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericTextField.cs
index bd3a045..f324c9b 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericTextField.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/NumericTextField.cs
@@ -25,8 +25,8 @@ namespace Xamarin.PropertyEditing.Mac
 			get; set;
 		}
 
-		public event EventHandler KeyArrowUp;
-		public event EventHandler KeyArrowDown;
+		public event EventHandler<bool> KeyArrowUp;
+		public event EventHandler<bool> KeyArrowDown;
 		public event EventHandler ValidatedEditingEnded;
 
 		public NumericTextField ()
@@ -34,15 +34,15 @@ namespace Xamarin.PropertyEditing.Mac
 			AllowNegativeValues = true;
 
 			var keyUpDownDelegate = new KeyUpDownDelegate ();
-			keyUpDownDelegate.KeyArrowUp += (sender, e) => { OnKeyArrowUp (); };
-			keyUpDownDelegate.KeyArrowDown += (sender, e) => { OnKeyArrowDown (); };
+			keyUpDownDelegate.KeyArrowUp += (sender, e) => { OnKeyArrowUp (e); };
+			keyUpDownDelegate.KeyArrowDown += (sender, e) => { OnKeyArrowDown (e); };
 			Delegate = keyUpDownDelegate;
 		}
 
-		public override bool ShouldBeginEditing (NSText fieldEditor)
+		public override bool ShouldBeginEditing (NSText textObject)
 		{
-			CachedCurrentEditor = fieldEditor;
-			cachedValueString = fieldEditor.Value;
+			CachedCurrentEditor = textObject;
+			cachedValueString = textObject.Value;
 
 			if (AllowRatios)
 				CachedCurrentEditor.Delegate = new RatioValidateDelegate (this);
@@ -52,27 +52,19 @@ namespace Xamarin.PropertyEditing.Mac
 			return true;
 		}
 
-		protected virtual void OnKeyArrowUp ()
+		protected virtual void OnKeyArrowUp (bool shiftPressed)
 		{
-			var handler = KeyArrowUp;
-			if (handler != null) {
-				handler (this, EventArgs.Empty);
-			}
+			KeyArrowUp?.Invoke (this, shiftPressed);
 		}
 
-		protected virtual void OnKeyArrowDown ()
+		protected virtual void OnKeyArrowDown (bool shiftPressed)
 		{
-			var handler = KeyArrowDown;
-			if (handler != null) {
-				handler (this, EventArgs.Empty);
-			}
+			KeyArrowDown?.Invoke (this, shiftPressed);
 		}
 
-		public virtual void RaiseValidatedEditingEnded ()
+		public virtual void NotifyValidatedEditingEnded ()
 		{
-			var handler = ValidatedEditingEnded;
-			if (handler != null)
-				handler (this, EventArgs.Empty);
+			ValidatedEditingEnded?.Invoke (this, EventArgs.Empty);
 		}
 
 		public virtual void ResetInvalidInput ()
@@ -80,12 +72,66 @@ namespace Xamarin.PropertyEditing.Mac
 			this.StringValue = cachedValueString;
 		}
 
+		public static bool CheckIfNumber (string finalString, ValidationType mode, bool allowNegativeValues)
+		{
+			return mode == ValidationType.Decimal ?
+				ValidateDecimal (finalString, allowNegativeValues) :
+				ValidateInteger (finalString, allowNegativeValues);
+		}
+
+		public static bool ValidateDecimal (string finalString, bool allowNegativeValues)
+		{
+			double value;
+			//Checks parsing to number
+			if (!double.TryParse (finalString, System.Globalization.NumberStyles.Any, System.Globalization.CultureInfo.CurrentUICulture, out value))
+				return false;
+			//Checks if needs to be possitive value
+			if (!allowNegativeValues && value < 0)
+				return false;
+			//Checks a common validation
+			return ViewModels.RatioViewModel.IsValidInput (finalString);
+		}
+
+		public static bool ValidateInteger (string finalString, bool allowNegativeValues)
+		{
+			int value;
+			//Checks parsing to number
+			if (!int.TryParse (finalString, out value))
+				return false;
+			//Checks if needs to be possitive value
+			if (!allowNegativeValues && value < 0)
+				return false;
+			//Checks a common validation
+			return ViewModels.RatioViewModel.IsValidInput (finalString);
+		}
+
+		public static bool CheckIfRatio (string finalString, ValidationType mode, bool allowNegativeValues)
+		{
+			var parts = finalString.Split (ViewModels.RatioViewModel.SplitSeparators, StringSplitOptions.RemoveEmptyEntries);
+			if (parts.Length == 2) {
+				bool parsed = true;
+
+				if (!CheckIfNumber (parts[0], mode, allowNegativeValues))
+					parsed = false;
+
+				if (!String.IsNullOrEmpty (parts[1]) && !CheckIfNumber (parts[1], mode, allowNegativeValues))
+					parsed = false;
+
+				if (parsed)
+					return true;
+			} else if (parts.Length == 1) { // We have a potential whole number, let's make sure
+				if (CheckIfNumber (parts[0], mode, allowNegativeValues)) {
+					return true;
+				}
+			}
+			return false;
+		}
 	}
 
 	class KeyUpDownDelegate : NSTextFieldDelegate
 	{
-		public event EventHandler KeyArrowUp;
-		public event EventHandler KeyArrowDown;
+		public event EventHandler<bool> KeyArrowUp;
+		public event EventHandler<bool> KeyArrowDown;
 
 		public override bool DoCommandBySelector (NSControl control, NSTextView textView, Selector commandSelector)
 		{
@@ -96,27 +142,27 @@ namespace Xamarin.PropertyEditing.Mac
 				case "moveDown:":
 					OnKeyArrowDown ();
 					break;
+				case "moveUpAndModifySelection:":
+					OnKeyArrowUp (true);
+					break;
+				case "moveDownAndModifySelection:":
+					OnKeyArrowDown (true);
+					break;
 				default:
 					return false;
 			}
 
-			return false;
+			return true;
 		}
 
-		protected virtual void OnKeyArrowUp ()
+		protected virtual void OnKeyArrowUp (bool shiftPressed = false)
 		{
-			var handler = KeyArrowUp;
-			if (handler != null) {
-				handler (this, EventArgs.Empty);
-			}
+			KeyArrowUp?.Invoke (this, shiftPressed);
 		}
 
-		protected virtual void OnKeyArrowDown ()
+		protected virtual void OnKeyArrowDown (bool shiftPressed = false)
 		{
-			var handler = KeyArrowDown;
-			if (handler != null) {
-				handler (this, EventArgs.Empty);
-			}
+			KeyArrowDown?.Invoke (this, shiftPressed);
 		}
 	}
 
@@ -138,17 +184,22 @@ namespace Xamarin.PropertyEditing.Mac
 
 		public override bool TextShouldEndEditing (NSText textObject)
 		{
-			if (!ValidateFinalString (TextField.StringValue)) {
+			bool shouldEndEditing = false;
+			if (!ValidateFinalString (textObject.Value)) {
 				TextField.ResetInvalidInput ();
 				AppKitFramework.NSBeep ();
-				return false;
+				TextField.ShouldEndEditing (textObject);
+			} else {
+				shouldEndEditing = TextField.ShouldEndEditing (textObject);
 			}
-			return TextField.ShouldEndEditing (textObject);
+
+			return shouldEndEditing;
 		}
 
 		public override void TextDidEndEditing (NSNotification notification)
 		{
-			TextField.RaiseValidatedEditingEnded ();
+			TextField.NotifyValidatedEditingEnded ();
+			TextField.DidEndEditing (notification);
 		}
 
 		protected abstract bool ValidateFinalString (string value);
@@ -165,8 +216,8 @@ namespace Xamarin.PropertyEditing.Mac
 		protected override bool ValidateFinalString (string value)
 		{
 			return TextField.NumericMode == ValidationType.Decimal ?
-				FieldValidation.ValidateDecimal (value, TextField.AllowNegativeValues) :
-				FieldValidation.ValidateInteger (value, TextField.AllowNegativeValues);
+				            NumericTextField.ValidateDecimal (value, TextField.AllowNegativeValues) :
+				            NumericTextField.ValidateInteger (value, TextField.AllowNegativeValues);
 		}
 	}
 
@@ -180,7 +231,9 @@ namespace Xamarin.PropertyEditing.Mac
 
 		protected override bool ValidateFinalString (string value)
 		{
-			return FieldValidation.ValidateRatio (value, ValidationType.Decimal, TextField.AllowNegativeValues);
+			if (NumericTextField.CheckIfRatio (value, ValidationType.Decimal, false) || NumericTextField.CheckIfNumber (value, ValidationType.Decimal, false))
+				return true;
+			return false;
 		}
 	}
 }
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
index a300e18..77a2cb3 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
@@ -2,11 +2,12 @@
 using AppKit;
 using CoreGraphics;
 using Xamarin.PropertyEditing.Mac.Resources;
+using Xamarin.PropertyEditing.Themes;
 using Xamarin.PropertyEditing.ViewModels;
 
 namespace Xamarin.PropertyEditing.Mac
 {
-	public class PropertyButton : NSImageView
+	public class PropertyButton : UnfocusableButton
 	{
 		NSMenu popUpContextMenu;
 
@@ -35,106 +36,101 @@ namespace Xamarin.PropertyEditing.Mac
 			AccessibilityHelp = LocalizationResources.AccessibilityPropertiesButtonDescription;
 			Enabled = true;
 			Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-10");
-			ImageScaling = NSImageScale.AxesIndependently;
+			ImageScaling = NSImageScale.None;
 			ToolTip = Properties.Resources.Default;
 			TranslatesAutoresizingMaskIntoConstraints = false;
+
+			OnMouseEntered += (sender, e) => {
+				ToggleFocusImage (true);
+			};
+
+			OnMouseExited += (sender, e) => {
+				ToggleFocusImage ();
+			};
+
+			OnMouseLeftDown += (sender, e) => {
+				PopUpContextMenu ();
+			};
 		}
 
-		public override void MouseDown (NSEvent theEvent)
+		private void PopUpContextMenu ()
 		{
-			if (theEvent.Type == NSEventType.LeftMouseDown) {
-				if (this.popUpContextMenu == null) {
-					this.popUpContextMenu = new NSMenu ();
-
-					if (this.viewModel.TargetPlatform.SupportsCustomExpressions) {
-						var mi = new NSMenuItem (Properties.Resources.CustomExpressionEllipsis) {
-							AttributedTitle = new Foundation.NSAttributedString (
-							Properties.Resources.CustomExpressionEllipsis,
-							new CoreText.CTStringAttributes () {
-									Font = new CoreText.CTFont (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultFontSize + 1),
-							})
-						};
-
-						mi.Activated += OnCustomExpression;
-
-						this.popUpContextMenu.AddItem (mi);
-						this.popUpContextMenu.AddItem (NSMenuItem.SeparatorItem);
-					}
-
-					// TODO If we add more menu items consider making the Label/Command a dictionary that we can iterate over to populate everything.
-					this.popUpContextMenu.AddItem (new CommandMenuItem (Properties.Resources.Reset, viewModel.ClearValueCommand) {
+			if (this.popUpContextMenu == null) {
+				this.popUpContextMenu = new NSMenu ();
+
+				if (this.viewModel.TargetPlatform.SupportsCustomExpressions) {
+					var mi = new NSMenuItem (Properties.Resources.CustomExpressionEllipsis) {
 						AttributedTitle = new Foundation.NSAttributedString (
-							Properties.Resources.Reset,
-							new CoreText.CTStringAttributes () {
-								Font = new CoreText.CTFont (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultFontSize + 1),
-							})
-					});
-				}
+						Properties.Resources.CustomExpressionEllipsis,
+						new CoreText.CTStringAttributes () {
+							Font = new CoreText.CTFont (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultFontSize + 1),
+						})
+					};
 
-				var menuOrigin = this.Superview.ConvertPointToView (new CGPoint (Frame.Location.X - 1, Frame.Location.Y + Frame.Size.Height + 4), null);
+					mi.Activated += OnCustomExpression;
 
-				var popupMenuEvent = NSEvent.MouseEvent (NSEventType.LeftMouseDown, menuOrigin, (NSEventModifierMask)0x100, 0, this.Window.WindowNumber, this.Window.GraphicsContext, 0, 1, 1);
+					this.popUpContextMenu.AddItem (mi);
+					this.popUpContextMenu.AddItem (NSMenuItem.SeparatorItem);
+				}
 
-				NSMenu.PopUpContextMenu (popUpContextMenu, popupMenuEvent, this);
+				// TODO If we add more menu items consider making the Label/Command a dictionary that we can iterate over to populate everything.
+				this.popUpContextMenu.AddItem (new CommandMenuItem (Properties.Resources.Reset, viewModel.ClearValueCommand) {
+					AttributedTitle = new Foundation.NSAttributedString (
+						Properties.Resources.Reset,
+						new CoreText.CTStringAttributes () {
+							Font = new CoreText.CTFont (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultFontSize + 1),
+						})
+				});
 			}
-		}
 
-		public override void MouseEntered (NSEvent theEvent)
-		{
-			ChangeActiveImage (viewModel.ValueSource, true);
-		}
+			var menuOrigin = this.Superview.ConvertPointToView (new CGPoint (Frame.Location.X - 1, Frame.Location.Y + Frame.Size.Height + 4), null);
 
-		public override void MouseExited (NSEvent theEvent)
-		{
-			ChangeActiveImage (viewModel.ValueSource);
+			var popupMenuEvent = NSEvent.MouseEvent (NSEventType.LeftMouseDown, menuOrigin, (NSEventModifierMask)0x100, 0, this.Window.WindowNumber, this.Window.GraphicsContext, 0, 1, 1);
+
+			NSMenu.PopUpContextMenu (popUpContextMenu, popupMenuEvent, this);
 		}
 
-		public override void UpdateTrackingAreas ()
+		protected override void UpdateTheme ()
 		{
-			base.UpdateTrackingAreas ();
-
-			foreach (var item in TrackingAreas ()) {
-				RemoveTrackingArea (item);
-			}
-
-			var options = NSTrackingAreaOptions.MouseEnteredAndExited | NSTrackingAreaOptions.ActiveAlways;
+			base.UpdateTheme ();
 
-			var trackingArea = new NSTrackingArea (this.Bounds, options, this, null);
-
-			AddTrackingArea (trackingArea);
+			ToggleFocusImage ();
 		}
 
-		private void ChangeActiveImage (ValueSource valueSource, bool activeImage = false)
+		private void ToggleFocusImage (bool focused = false)
 		{
-			switch (valueSource) {
+			if (viewModel != null) {
+				
+				switch (viewModel.ValueSource) {
 				case ValueSource.Binding:
-					Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-bound-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-bound-mac-10");
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-bound-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-bound-mac-10");
 					break;
 
 				case ValueSource.Default:
-					Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-10");
-					return;
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-10");
+					break;
 
 				case ValueSource.Local:
-					Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-local-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-local-mac-10");
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-local-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-local-mac-10");
 					break;
 
 				case ValueSource.Inherited:
-					Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-10");
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-10");
 					break;
 
 				case ValueSource.Resource:
-					Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-10");
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-inherited-mac-10");
 					break;
 
 				case ValueSource.Unset:
-				Image = activeImage ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-10");
+					Image = focused ? PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-active-10") : PropertyEditorPanel.ThemeManager.GetImageForTheme ("property-button-default-mac-10");
 					break;
 
 				default:
 					// To Handle ValueSource.DefaultStyle, ValueSource.Style etc.
 					Image = null;
 					break;
+				}
 			}
 		}
 
@@ -171,7 +167,7 @@ namespace Xamarin.PropertyEditing.Mac
 					break;
 			}
 
-			ChangeActiveImage (valueSource, false);
+			UpdateTheme ();
 		}
 
 		private void OnPropertyChanged (object sender, System.ComponentModel.PropertyChangedEventArgs e)
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/RatioEditor.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/RatioEditor.cs
new file mode 100644
index 0000000..507eee3
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/RatioEditor.cs
@@ -0,0 +1,80 @@
+using System;
+using AppKit;
+using Foundation;
+using Xamarin.PropertyEditing.Drawing;
+using Xamarin.PropertyEditing.Mac;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class RatioEditor<T> : NumericSpinEditor<T>
+	{
+		private bool fullSelection;
+
+		public RatioEditor ()
+		{
+			AllowNegativeValues = false;
+			AllowRatios = true;
+			BackgroundColor = NSColor.Clear;
+			StringValue = string.Empty;
+			TranslatesAutoresizingMaskIntoConstraints = false;
+		}
+
+		protected override void OnEditingEnded (object sender, EventArgs e)
+		{
+			if (!editing) {
+				editing = true;
+				NotifyingValueChanged (new RatioEventArgs (0, 0, 0));
+				editing = false;
+			}
+		}
+
+		protected override void SetIncrementOrDecrementValue (double incDevValue)
+		{
+			nint caretLocation = 0;
+			nint selectionLength = 0;
+
+			GetEditorCaretLocationAndLength (out caretLocation, out selectionLength);
+
+			// Fire A Value change, so things are updated
+			NotifyingValueChanged (new RatioEventArgs ((int)caretLocation, (int)selectionLength, incDevValue));
+
+			// Resposition our caret so it doesn't jump around.
+			SetEditorCaretLocationAndLength (caretLocation, selectionLength);
+		}
+
+		private void SetEditorCaretLocationAndLength (nint caretLocation, nint selectionLength)
+		{
+			if (NumericEditor.CurrentEditor != null) {
+				if (fullSelection && (selectionLength != NumericEditor.StringValue.Length)) {
+					selectionLength = NumericEditor.StringValue.Length;
+				}
+				NumericEditor.CurrentEditor.SelectedRange = new NSRange (caretLocation, selectionLength);
+			}
+		}
+
+		private void GetEditorCaretLocationAndLength (out nint caretLocation, out nint selectionLength)
+		{
+			caretLocation = 0;
+			selectionLength = 0;
+			if (NumericEditor.CurrentEditor != null) {
+				caretLocation = NumericEditor.CurrentEditor.SelectedRange.Location;
+				selectionLength = NumericEditor.CurrentEditor.SelectedRange.Length;
+				fullSelection = NumericEditor.StringValue.Length == selectionLength;
+			}
+		}
+
+		public class RatioEventArgs : EventArgs
+		{
+			public RatioEventArgs (int caretPosition, int selectionLength, double incrementValue)
+			{
+				CaretPosition = caretPosition;
+				SelectionLength = selectionLength;
+				IncrementValue = incrementValue;
+			}
+
+			public int CaretPosition { get; }
+			public int SelectionLength { get; }
+			public double IncrementValue { get; }
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs
new file mode 100644
index 0000000..0ba72dc
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs
@@ -0,0 +1,49 @@
+using System;
+using AppKit;
+using ObjCRuntime;
+using Xamarin.PropertyEditing.Themes;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	public class UpSpinnerButton : UnfocusableButton
+	{
+		public UpSpinnerButton ()
+		{
+			OnMouseEntered += (sender, e) => {
+				Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-up-focus-blue");
+			};
+
+			OnMouseExited += (sender, e) => {
+				Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-up");
+			};
+		}
+
+		protected override void UpdateTheme ()
+		{
+			base.UpdateTheme ();
+
+			Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-up");
+		}
+	}
+
+	public class DownSpinnerButton : UnfocusableButton
+	{
+		public DownSpinnerButton ()
+		{
+			OnMouseEntered += (sender, e) => {
+				Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-down-focus-blue");
+			};
+
+			OnMouseExited += (sender, e) => {
+				Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-down");
+			};
+		}
+
+		protected override void UpdateTheme ()
+		{
+			base.UpdateTheme ();
+
+			Image = PropertyEditorPanel.ThemeManager.GetImageForTheme ("stepper-down");
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs
new file mode 100644
index 0000000..3a18805
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs
@@ -0,0 +1,104 @@
+using System;
+using AppKit;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	public abstract class UnfocusableButton : NSImageView
+	{
+		public event EventHandler OnMouseEntered;
+		public event EventHandler OnMouseExited;
+		public event EventHandler OnMouseLeftDown;
+		public event EventHandler OnMouseRightDown;
+
+		public UnfocusableButton ()
+		{
+			Enabled = true;
+			ImageScaling = NSImageScale.AxesIndependently;
+			TranslatesAutoresizingMaskIntoConstraints = false;
+
+			PropertyEditorPanel.ThemeManager.ThemeChanged += ThemeManager_ThemeChanged;
+
+			UpdateTheme ();
+		}
+
+		#region Overridden Methods
+		protected override void Dispose (bool disposing)
+		{
+			if (disposing) {
+				PropertyEditorPanel.ThemeManager.ThemeChanged -= ThemeManager_ThemeChanged;
+			}
+		}
+
+		public override void MouseDown (NSEvent theEvent)
+		{
+			switch (theEvent.Type) {
+				case NSEventType.LeftMouseDown:
+					NotifyMouseLeftDown ();
+					break;
+
+				case NSEventType.RightMouseDown:
+					NotifyMouseRightDown ();
+					break;
+			}
+		}
+
+		public override void MouseEntered (NSEvent theEvent)
+		{
+			NotifyMouseEntered ();
+		}
+
+		public override void MouseExited (NSEvent theEvent)
+		{
+			NotifyMouseExited ();
+		}
+
+		public override void UpdateTrackingAreas ()
+		{
+			base.UpdateTrackingAreas ();
+
+			foreach (var item in TrackingAreas ()) {
+				RemoveTrackingArea (item);
+			}
+
+			var options = NSTrackingAreaOptions.MouseEnteredAndExited | NSTrackingAreaOptions.ActiveAlways;
+
+			var trackingArea = new NSTrackingArea (this.Bounds, options, this, null);
+
+			AddTrackingArea (trackingArea);
+		}
+		#endregion
+
+
+		#region Local Methods
+		private void NotifyMouseEntered ()
+		{
+			OnMouseEntered?.Invoke (this, EventArgs.Empty);
+		}
+
+		private void NotifyMouseExited ()
+		{
+			OnMouseExited?.Invoke (this, EventArgs.Empty);
+		}
+
+		private void NotifyMouseLeftDown ()
+		{
+			OnMouseLeftDown?.Invoke (this, EventArgs.Empty);
+		}
+
+		private void NotifyMouseRightDown ()
+		{
+			OnMouseRightDown?.Invoke (this, EventArgs.Empty);
+		}
+
+		void ThemeManager_ThemeChanged (object sender, EventArgs e)
+		{
+			UpdateTheme ();
+		}
+
+		protected virtual void UpdateTheme ()
+		{
+			this.Appearance = PropertyEditorPanel.ThemeManager.CurrentAppearance;
+		}
+		#endregion
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/Controls/NumericEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/NumericEditorControl.cs
index 916957a..b0ab2b9 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/NumericEditorControl.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/NumericEditorControl.cs
@@ -57,7 +57,7 @@ namespace Xamarin.PropertyEditing.Mac
 		}
 
 		public override NSView FirstKeyView => NumericEditor;
-		public override NSView LastKeyView => NumericEditor;
+		public override NSView LastKeyView => NumericEditor.DecrementButton;
 
 		protected NSNumberFormatterStyle NumberStyle {
 			get { 
diff --git a/Xamarin.PropertyEditing.Mac/Controls/PropertyEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/PropertyEditorControl.cs
index 04c7c48..d4cc0d6 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/PropertyEditorControl.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/PropertyEditorControl.cs
@@ -54,7 +54,7 @@ namespace Xamarin.PropertyEditing.Mac
 			}
 		}
 
-		public void UpdateKeyViews (bool backward = true, bool forward = true)
+		public void UpdateKeyViews ()
 		{
 			if (TableRow < 0)
 				return;
@@ -62,15 +62,17 @@ namespace Xamarin.PropertyEditing.Mac
 			PropertyEditorControl ctrl = null;
 
 			//FIXME: don't hardcode column
-			if (backward && TableRow > 0 && (ctrl = TableView.GetView (1, TableRow - 1, false) as PropertyEditorControl) != null) {
-				ctrl.LastKeyView.NextKeyView = FirstKeyView;
-				ctrl.UpdateKeyViews (forward: false);
-			}
-
-			//FIXME: don't hardcode column
-			if (forward && TableRow < TableView.RowCount - 1 && (ctrl = TableView.GetView (1, TableRow + 1, false) as PropertyEditorControl) != null) {
-				LastKeyView.NextKeyView = ctrl.FirstKeyView;
-				ctrl.UpdateKeyViews (backward: false);
+			var tr = TableRow;
+			if (tr > 0) {
+				do {
+					tr--;
+					ctrl = TableView.GetView (1, tr, false) as PropertyEditorControl;
+				} while (tr > 0 && ctrl == null);
+
+				if (ctrl != null) {
+					ctrl.LastKeyView.NextKeyView = FirstKeyView;
+					ctrl.UpdateKeyViews ();
+				}
 			}
 		}
 
diff --git a/Xamarin.PropertyEditing.Mac/Controls/RatioEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/RatioEditorControl.cs
new file mode 100644
index 0000000..a859652
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Controls/RatioEditorControl.cs
@@ -0,0 +1,78 @@
+using System;
+using System.Collections;
+using System.ComponentModel;
+using AppKit;
+using Xamarin.PropertyEditing.Mac.Resources;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class RatioEditorControl<T> : PropertyEditorControl<RatioViewModel>
+	{
+		RatioEditor<T> ratioEditor;
+
+		public RatioEditorControl ()
+		{
+			base.TranslatesAutoresizingMaskIntoConstraints = false;
+
+			ratioEditor = new RatioEditor<T> {
+				AllowNegativeValues = false,
+				AllowRatios = true,
+				BackgroundColor = NSColor.Clear,
+				StringValue = string.Empty,
+				TranslatesAutoresizingMaskIntoConstraints = false,
+			};
+
+			// update the value on keypress
+			ratioEditor.ValueChanged += (sender, e) => {
+				if (e is RatioEditor<T>.RatioEventArgs ratioEventArgs) {
+					ViewModel.ValueChanged (ratioEditor.StringValue, ratioEventArgs.CaretPosition, ratioEventArgs.SelectionLength, ratioEventArgs.IncrementValue);
+				}
+			};
+			AddSubview (ratioEditor);
+
+			this.DoConstraints (new[] {
+				ratioEditor.ConstraintTo (this, (re, c) => re.Top == c.Top - 2),
+				ratioEditor.ConstraintTo (this, (re, c) => re.Left == c.Left + 4),
+				ratioEditor.ConstraintTo (this, (re, c) => re.Width == c.Width - 33),
+				ratioEditor.ConstraintTo (this, (re, c) => re.Height == DefaultControlHeight),
+			});
+
+			UpdateTheme ();
+		}
+
+		public override NSView FirstKeyView => ratioEditor.NumericEditor;
+		public override NSView LastKeyView => ratioEditor.DecrementButton;
+
+		protected override void HandleErrorsChanged (object sender, DataErrorsChangedEventArgs e)
+		{
+			UpdateErrorsDisplayed (ViewModel.GetErrors (ViewModel.Property.Name));
+		}
+
+		protected override void SetEnabled ()
+		{
+			ratioEditor.Editable = ViewModel.Property.CanWrite;
+		}
+
+		protected override void UpdateAccessibilityValues ()
+		{
+			ratioEditor.AccessibilityEnabled = ratioEditor.Enabled;
+			ratioEditor.AccessibilityTitle = string.Format (LocalizationResources.AccessibilityNumeric, ViewModel.Property.Name);
+		}
+
+		protected override void UpdateErrorsDisplayed (IEnumerable errors)
+		{
+			if (ViewModel.HasErrors) {
+				SetErrors (errors);
+			} else {
+				SetErrors (null);
+				SetEnabled ();
+			}
+		}
+
+		protected override void UpdateValue ()
+		{
+			ratioEditor.StringValue = ViewModel.ValueString;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs b/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
index db257b7..511b8fd 100644
--- a/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
+++ b/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
@@ -247,6 +247,8 @@ namespace Xamarin.PropertyEditing.Mac
 			{typeof (PropertyViewModel<Point>), typeof (SystemPointEditorControl)},
 			{typeof (PropertyViewModel<Size>), typeof (SystemSizeEditorControl)},
 			{typeof (PropertyViewModel<Rectangle>), typeof (SystemRectangleEditorControl)},
-			{typeof (BrushPropertyViewModel), typeof (BrushEditorControl) }};
+			{typeof (BrushPropertyViewModel), typeof (BrushEditorControl)},
+			{typeof (RatioViewModel), typeof (RatioEditorControl<CommonRatio>)},
+		};
 	}
 }
diff --git a/Xamarin.PropertyEditing.Mac/Resources/stepper-down.png b/Xamarin.PropertyEditing.Mac/Resources/stepper-down.png
new file mode 100644
index 0000000..45c0fc6
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Resources/stepper-down.png
diff --git a/Xamarin.PropertyEditing.Mac/Resources/stepper-down@2x.png b/Xamarin.PropertyEditing.Mac/Resources/stepper-down@2x.png
new file mode 100644
index 0000000..c76f383
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Resources/stepper-down@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/Resources/stepper-up.png b/Xamarin.PropertyEditing.Mac/Resources/stepper-up.png
new file mode 100644
index 0000000..496d2f8
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Resources/stepper-up.png
diff --git a/Xamarin.PropertyEditing.Mac/Resources/stepper-up@2x.png b/Xamarin.PropertyEditing.Mac/Resources/stepper-up@2x.png
new file mode 100644
index 0000000..32792d0
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/Resources/stepper-up@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/Xamarin.PropertyEditing.Mac.csproj b/Xamarin.PropertyEditing.Mac/Xamarin.PropertyEditing.Mac.csproj
index c2f7a98..ba046cb 100644
--- a/Xamarin.PropertyEditing.Mac/Xamarin.PropertyEditing.Mac.csproj
+++ b/Xamarin.PropertyEditing.Mac/Xamarin.PropertyEditing.Mac.csproj
@@ -1,253 +1,268 @@
-<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <PropertyGroup>
-    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
-    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
-    <ProjectGuid>{E8F4F0EB-C2B1-4116-8459-E076E0E0E485}</ProjectGuid>
-    <ProjectTypeGuids>{A3F8F2AB-B479-4A4A-A458-A89E7DC349F1};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
-    <OutputType>Library</OutputType>
-    <RootNamespace>Xamarin.PropertyEditing.Mac</RootNamespace>
-    <AssemblyName>Xamarin.PropertyEditing.Mac</AssemblyName>
-    <TargetFrameworkVersion>v4.6</TargetFrameworkVersion>
-    <MonoMacResourcePrefix>Resources</MonoMacResourcePrefix>
-    <TargetFrameworkProfile />
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
-    <DebugSymbols>true</DebugSymbols>
-    <DebugType>full</DebugType>
-    <Optimize>false</Optimize>
-    <OutputPath>bin\Debug</OutputPath>
-    <DefineConstants>DEBUG;</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <EnableCodeSigning>false</EnableCodeSigning>
-    <CreatePackage>false</CreatePackage>
-    <EnablePackageSigning>false</EnablePackageSigning>
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+    <BundleResource Include="Resources\property-button-inherited-mac-10.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-10%402x.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-10~dark.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-10~dark%402x.png" />

+    <BundleResource Include="Resources\property-button-local-mac-10.png" />

+    <BundleResource Include="Resources\property-button-local-mac-10%402x.png" />

+    <BundleResource Include="Resources\property-button-local-mac-10~dark.png" />

+    <BundleResource Include="Resources\property-button-local-mac-10~dark%402x.png" />

+    <BundleResource Include="Resources\property-button-bound-mac-active-10.png" />

+    <BundleResource Include="Resources\property-button-bound-mac-active-10%402x.png" />

+    <BundleResource Include="Resources\property-button-bound-mac-active-10~dark.png" />

+    <BundleResource Include="Resources\property-button-bound-mac-active-10~dark%402x.png" />

+    <BundleResource Include="Resources\property-button-default-mac-active-10.png" />

+    <BundleResource Include="Resources\property-button-default-mac-active-10%402x.png" />

+    <BundleResource Include="Resources\property-button-default-mac-active-10~dark.png" />

+    <BundleResource Include="Resources\property-button-default-mac-active-10~dark%402x.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-active-10.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-active-10%402x.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-active-10~dark.png" />

+    <BundleResource Include="Resources\property-button-inherited-mac-active-10~dark%402x.png" />

+    <BundleResource Include="Resources\property-button-local-mac-active-10.png" />

+    <BundleResource Include="Resources\property-button-local-mac-active-10%402x.png" />

+    <BundleResource Include="Resources\property-button-local-mac-active-10~dark.png" />

+    <BundleResource Include="Resources\property-button-local-mac-active-10~dark%402x.png" />

+    <BundleResource Include="Resources\custom-expression-32.png" />

+    <BundleResource Include="Resources\custom-expression-32%402x.png" />

+    <BundleResource Include="Resources\custom-expression-32~dark.png" />

+    <BundleResource Include="Resources\custom-expression-32~dark%402x.png" />

+    <BundleResource Include="Resources\stepper-down.png" />

+    <BundleResource Include="Resources\stepper-down%402x.png" />

+    <BundleResource Include="Resources\stepper-up.png" />

+    <BundleResource Include="Resources\stepper-up%402x.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-gradient-16~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-image-16.png" />

+    <BundleResource Include="Resources\property-brush-image-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-image-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-image-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-image-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-image-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-image-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-image-16~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-none-16.png" />

+    <BundleResource Include="Resources\property-brush-none-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-none-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-none-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-none-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-none-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-none-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-none-16~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-palette-16.png" />

+    <BundleResource Include="Resources\property-brush-palette-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-palette-16~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-resources-16.png" />

+    <BundleResource Include="Resources\property-brush-resources-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-resources-16~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-solid-16.png" />

+    <BundleResource Include="Resources\property-brush-solid-16%402x.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~dark.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~dark%402x.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~dark~sel.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~dark~sel%402x.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~sel.png" />

+    <BundleResource Include="Resources\property-brush-solid-16~sel%402x.png" />

+  </ItemGroup>

+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\Mac\Xamarin.Mac.CSharp.targets" />

+</Project>

diff --git a/Xamarin.PropertyEditing.Tests/ConstrainedPropertyViewModelTests.cs b/Xamarin.PropertyEditing.Tests/ConstrainedPropertyViewModelTests.cs
index c14e390..654683a 100644
--- a/Xamarin.PropertyEditing.Tests/ConstrainedPropertyViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/ConstrainedPropertyViewModelTests.cs
@@ -108,10 +108,5 @@ namespace Xamarin.PropertyEditing.Tests
 
 		protected abstract T GetConstrainedRandomValueAboveBounds (Random rand, out T max, out T min);
 		protected abstract T GetConstrainedRandomValueBelowBounds (Random rand, out T max, out T min);
-
-		protected TViewModel GetViewModel (IPropertyInfo property, IObjectEditor editor)
-		{
-			return GetViewModel (property, new[] { editor });
-		}
 	}
 }
diff --git a/Xamarin.PropertyEditing.Tests/MockControls/MockSampleControl.cs b/Xamarin.PropertyEditing.Tests/MockControls/MockSampleControl.cs
index 32d8d6f..faafc83 100644
--- a/Xamarin.PropertyEditing.Tests/MockControls/MockSampleControl.cs
+++ b/Xamarin.PropertyEditing.Tests/MockControls/MockSampleControl.cs
@@ -22,6 +22,7 @@ namespace Xamarin.PropertyEditing.Tests.MockControls
 			AddProperty<CommonPoint> ("Point", ReadWrite);
 			AddProperty<CommonSize> ("Size", ReadWrite);
 			AddProperty<CommonRectangle> ("Rectangle", ReadWrite);
+			AddProperty<CommonRatio> ("Ratio", ReadWrite);
 			// AddProperty<CommonThickness> ("Thickness", ReadWrite); // Lacking support on the mac at this point in time.
 			AddProperty<object> ("Object", ReadWrite);
 			AddProperty<IList> ("Collection", ReadWrite);
@@ -36,6 +37,7 @@ namespace Xamarin.PropertyEditing.Tests.MockControls
 			AddReadOnlyProperty<CommonPoint> ("ReadOnlyPoint", ReadOnly);
 			AddReadOnlyProperty<CommonSize> ("ReadOnlySize", ReadOnly);
 			AddReadOnlyProperty<CommonRectangle> ("ReadOnlyRectangle", ReadOnly);
+			AddReadOnlyProperty<CommonRatio> ("ReadOnlyRatio", ReadOnly);
 			// AddReadOnlyProperty<CommonThickness> ("ReadOnlyThickness", ReadOnly);
 
 			AddProperty<NotImplemented> ("Uncategorized", None);
diff --git a/Xamarin.PropertyEditing.Tests/MockControls/MockWpfControl.cs b/Xamarin.PropertyEditing.Tests/MockControls/MockWpfControl.cs
index e9f9680..c9eb3fb 100644
--- a/Xamarin.PropertyEditing.Tests/MockControls/MockWpfControl.cs
+++ b/Xamarin.PropertyEditing.Tests/MockControls/MockWpfControl.cs
@@ -105,6 +105,7 @@ namespace Xamarin.PropertyEditing.Tests.MockControls
 			AddProperty<VerticalAlignment> ("VerticalContentAlignment", Layout);
 			AddProperty<Visibility> ("Visibility");
 			AddProperty<double> ("Width");
+			AddProperty<CommonRatio> ("Ratio");
 			#endregion
 			#region Events
 			AddEvents (
diff --git a/Xamarin.PropertyEditing.Tests/ObservableLookupTests.cs b/Xamarin.PropertyEditing.Tests/ObservableLookupTests.cs
index 6bb2968..c0ab5b7 100644
--- a/Xamarin.PropertyEditing.Tests/ObservableLookupTests.cs
+++ b/Xamarin.PropertyEditing.Tests/ObservableLookupTests.cs
@@ -56,7 +56,7 @@ namespace Xamarin.PropertyEditing.Tests
 			var grouping = lookup[key];
 			((INotifyCollectionChanged) grouping).CollectionChanged += (sender, args) => {
 				if (args.Action == NotifyCollectionChangedAction.Remove) {
-					if (args.OldItems[0] == value)
+					if ((string)args.OldItems[0] == value)
 						itemRemoved = true;
 				}
 			};
diff --git a/Xamarin.PropertyEditing.Tests/PanelViewModelTests.cs b/Xamarin.PropertyEditing.Tests/PanelViewModelTests.cs
index a00ccd8..7b51e8f 100644
--- a/Xamarin.PropertyEditing.Tests/PanelViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/PanelViewModelTests.cs
@@ -18,8 +18,9 @@ namespace Xamarin.PropertyEditing.Tests
 		: PropertiesViewModelTests<PanelViewModel>
 	{
 		[SetUp]
-		public void Setup ()
+		public override void Setup ()
 		{
+			base.Setup ();
 			SynchronizationContext.SetSynchronizationContext (this.context = new TestContext ());
 		}
 
diff --git a/Xamarin.PropertyEditing.Tests/PropertiesViewModelTests.cs b/Xamarin.PropertyEditing.Tests/PropertiesViewModelTests.cs
index 8bd7ae2..a7e98a9 100644
--- a/Xamarin.PropertyEditing.Tests/PropertiesViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/PropertiesViewModelTests.cs
@@ -37,7 +37,7 @@ namespace Xamarin.PropertyEditing.Tests
 
 		private Exception unhandled;
 		[SetUp]
-		public void Setup ()
+		public virtual void Setup ()
 		{
 			AppDomain.CurrentDomain.UnhandledException += CurrentDomainOnUnhandledException;
 		}
diff --git a/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs b/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
index 8232d80..f206158 100644
--- a/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
@@ -429,7 +429,7 @@ namespace Xamarin.PropertyEditing.Tests
 			resourcesMock.Setup (rp => rp.GetResourcesAsync (editor.Target, mockProperty.Object, It.IsAny<CancellationToken> ())).ReturnsAsync (new[] { resource });
 
 			editor.ValueEvaluator = (info, val, source) => {
-				if (source == resource)
+				if ((Resource)source == resource)
 					return value;
 
 				return default(TValue);
diff --git a/Xamarin.PropertyEditing.Tests/RatioViewModelTests.cs b/Xamarin.PropertyEditing.Tests/RatioViewModelTests.cs
new file mode 100644
index 0000000..9aeedd0
--- /dev/null
+++ b/Xamarin.PropertyEditing.Tests/RatioViewModelTests.cs
@@ -0,0 +1,194 @@
+using System;
+using System.Collections.Generic;
+using NUnit.Framework;
+using Xamarin.PropertyEditing.Drawing;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Tests
+{
+	internal class RatioViewModelTests
+		: PropertyViewModelTests<CommonRatio, RatioViewModel>
+	{
+		[Test]
+		public void Numerator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+			Assume.That (vm.Value, Is.EqualTo (new CommonRatio ()));
+
+			bool xChanged = false, valueChanged = false;
+			vm.PropertyChanged += (sender, args) => {
+				if (args.PropertyName == nameof(RatioViewModel.Numerator))
+					xChanged = true;
+				if (args.PropertyName == nameof(RatioViewModel.Value))
+					valueChanged = true;
+			};
+
+			vm.Numerator = 5;
+			Assert.That (vm.Value.Numerator, Is.EqualTo (5));
+			Assert.That (xChanged, Is.True);
+			Assert.That (valueChanged, Is.True);
+		}
+
+		[Test]
+		public void Denominator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+			Assume.That (vm.Value, Is.EqualTo (new CommonRatio ()));
+
+			bool xChanged = false, valueChanged = false;
+			vm.PropertyChanged += (sender, args) => {
+				if (args.PropertyName == nameof (RatioViewModel.Denominator))
+					xChanged = true;
+				if (args.PropertyName == nameof (RatioViewModel.Value))
+					valueChanged = true;
+			};
+
+			vm.Denominator = 5;
+			Assert.That (vm.Value.Denominator, Is.EqualTo (5));
+			Assert.That (xChanged, Is.True);
+			Assert.That (valueChanged, Is.True);
+		}
+
+		[Test]
+		public void RatioSeparator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+			Assume.That (vm.Value, Is.EqualTo (new CommonRatio ()));
+
+			bool xChanged = false, valueChanged = false;
+			vm.PropertyChanged += (sender, args) => {
+				if (args.PropertyName == nameof (RatioViewModel.RatioSeparator))
+					xChanged = true;
+				if (args.PropertyName == nameof (RatioViewModel.Value))
+					valueChanged = true;
+			};
+
+			vm.RatioSeparator = '/';
+			Assert.That (vm.Value.RatioSeparator, Is.EqualTo ('/'));
+			Assert.That (xChanged, Is.True);
+			Assert.That (valueChanged, Is.True);
+		}
+
+		[Test]
+		public void ValueChangesNumeratorDenominatorRatioSeparator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+			Assume.That (vm.Numerator, Is.EqualTo (0));
+			Assume.That (vm.Denominator, Is.EqualTo (0));
+
+			bool nChanged = false, dChanged = false, sChanged = false, valueChanged = false;
+			vm.PropertyChanged += (sender, args) => {
+				if (args.PropertyName == nameof(RatioViewModel.Numerator))
+					nChanged = true;
+				if (args.PropertyName == nameof(RatioViewModel.Denominator))
+					dChanged = true;
+				if (args.PropertyName == nameof (RatioViewModel.RatioSeparator))
+					sChanged = true;
+				if (args.PropertyName == nameof(SizePropertyViewModel.Value))
+					valueChanged = true;
+			};
+
+			vm.Value = new CommonRatio (5, 10, ':');
+
+			Assert.That (vm.Numerator, Is.EqualTo (5));
+			Assert.That (vm.Denominator, Is.EqualTo (10));
+			Assert.That (nChanged, Is.True);
+			Assert.That (dChanged, Is.True);
+			Assert.That (sChanged, Is.True);
+			Assert.That (valueChanged, Is.True);
+		}
+
+		[Test]
+		public void RatioWithoutDenominator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+
+			vm.ValueString = "21";
+
+			Assert.That (vm.Numerator, Is.EqualTo (21));
+			Assert.That (vm.Denominator, Is.EqualTo (1));
+			Assert.That (vm.RatioSeparator, Is.EqualTo (':'));
+		}
+
+		[Test]
+		public void RatioWithNumeratorDenominatorAndColonSeparator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+
+			vm.ValueString = "21:2";
+
+			Assert.That (vm.Numerator, Is.EqualTo (21));
+			Assert.That (vm.Denominator, Is.EqualTo (2));
+			Assert.That (vm.RatioSeparator, Is.EqualTo (':'));
+		}
+
+		[Test]
+		public void RatioWithNumeratorDenominatorAndSlashSeparator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+
+			vm.ValueString = "21/2";
+
+			Assert.That (vm.Numerator, Is.EqualTo (21));
+			Assert.That (vm.Denominator, Is.EqualTo (2));
+			Assert.That (vm.RatioSeparator, Is.EqualTo ('/'));
+		}
+
+		[Test]
+		public void RatioWithWrongSeparator ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+			bool eChanged = false;
+			vm.ErrorsChanged += (sender, args) => {
+				eChanged = true;
+			};
+
+			vm.ValueString = "21@2";
+
+			// Was Error raised?
+			Assert.That (eChanged, Is.True);
+		}
+
+		[Test]
+		public void RatioWithSpaces ()
+		{
+			var property = GetPropertyMock ();
+			var editor = GetBasicEditor (property.Object);
+			var vm = GetViewModel (property.Object, new[] { editor });
+
+			vm.ValueString = " 21: 2 ";
+
+			Assert.That (vm.ValueString, Is.EqualTo ("21:2"));
+		}
+
+		protected override CommonRatio GetRandomTestValue (Random rand)
+		{
+			var randomDenominator = rand.Next ();
+			// Can't be less than 1
+			if (randomDenominator < 1) 
+				randomDenominator = 1;
+			return new CommonRatio (rand.Next (), randomDenominator, '/');
+		}
+
+		protected override RatioViewModel GetViewModel (TargetPlatform platform, IPropertyInfo property, IEnumerable<IObjectEditor> editors)
+		{
+			return new RatioViewModel (platform, property, editors);
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Tests/Xamarin.PropertyEditing.Tests.csproj b/Xamarin.PropertyEditing.Tests/Xamarin.PropertyEditing.Tests.csproj
index ba02175..c5419cd 100644
--- a/Xamarin.PropertyEditing.Tests/Xamarin.PropertyEditing.Tests.csproj
+++ b/Xamarin.PropertyEditing.Tests/Xamarin.PropertyEditing.Tests.csproj
@@ -119,6 +119,7 @@
     <Compile Include="ValueInfoTests.cs" />
     <Compile Include="MockControls\MockNSControl.cs" />
     <Compile Include="MockControls\MockNSButton.cs" />
+    <Compile Include="RatioViewModelTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Manual\BrushEditor.md" />
diff --git a/Xamarin.PropertyEditing.Windows/EditorPropertySelector.cs b/Xamarin.PropertyEditing.Windows/EditorPropertySelector.cs
index 9cddbe8..45994e4 100644
--- a/Xamarin.PropertyEditing.Windows/EditorPropertySelector.cs
+++ b/Xamarin.PropertyEditing.Windows/EditorPropertySelector.cs
@@ -109,7 +109,7 @@ namespace Xamarin.PropertyEditing.Windows
 			{ typeof(PropertyGroupViewModel), typeof(GroupEditorControl) },
 			{ typeof(ObjectPropertyViewModel), typeof(ObjectEditorControl) },
 			{ typeof(CollectionPropertyViewModel), typeof(CollectionEditor) },
-
+			{ typeof(RatioViewModel), typeof(RatioEditorControl) },
 		};
 	}
 }
diff --git a/Xamarin.PropertyEditing.Windows/RatioEditorControl.cs b/Xamarin.PropertyEditing.Windows/RatioEditorControl.cs
new file mode 100644
index 0000000..89cb8d1
--- /dev/null
+++ b/Xamarin.PropertyEditing.Windows/RatioEditorControl.cs
@@ -0,0 +1,44 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Controls;
+using System.Windows.Input;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Windows
+{
+	class RatioEditorControl : PropertyEditorControl
+	{
+		private RatioViewModel ViewModel => DataContext as RatioViewModel;
+		TextBoxEx ratioTextBox;
+
+		protected override void OnPreviewKeyDown (KeyEventArgs e)
+		{
+			ratioTextBox = e.Source as TextBoxEx;
+			var incValue = e.KeyboardDevice.IsKeyDown (Key.LeftShift) || e.KeyboardDevice.IsKeyDown (Key.RightShift) ? 10 : 1;
+			switch (e.Key) {
+			case Key.Up:
+				// Increment Value
+				ValueChanged (ratioTextBox.Text, ratioTextBox.CaretIndex, ratioTextBox.SelectionLength, incValue);
+				e.Handled = true;
+				break;
+			case Key.Down:
+				// Decrement Value
+				ValueChanged (ratioTextBox.Text, ratioTextBox.CaretIndex, ratioTextBox.SelectionLength, -incValue);
+				e.Handled = true;
+				break;
+			}
+
+			base.OnPreviewKeyDown (e);
+		}
+
+		void ValueChanged (string inputedText, int caretPosition, int selectionLength, double incrementValue)
+		{
+			ViewModel.ValueChanged (inputedText, caretPosition, selectionLength, incrementValue);
+			ratioTextBox.CaretIndex = caretPosition;
+			ratioTextBox.SelectionLength = selectionLength;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Windows/Themes/Resources.xaml b/Xamarin.PropertyEditing.Windows/Themes/Resources.xaml
index c068a9d..0772b60 100644
--- a/Xamarin.PropertyEditing.Windows/Themes/Resources.xaml
+++ b/Xamarin.PropertyEditing.Windows/Themes/Resources.xaml
@@ -317,21 +317,31 @@
     </Style>
 
     <Style TargetType="local:SizeEditorControl">
-	    <Setter Property="Template">
+        <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="local:SizeEditorControl">
                     <Grid>
-						<Grid.ColumnDefinitions>
-							<ColumnDefinition Width="Auto" />
-							<ColumnDefinition Width="*" />
-							<ColumnDefinition Width="Auto" />
-							<ColumnDefinition Width="*" />
-						</Grid.ColumnDefinitions>
-						<Label Grid.Column="0" Name="WidthLabel" Target="{Binding ElementName=WidthTextBox,Mode=OneTime}" Content="Width" />
-						<local:DoubleUpDownControl x:Name="WidthTextBox" Grid.Column="1" Value="{Binding Width}" IsEnabled="{Binding Property.CanWrite,Mode=OneTime}" AutomationProperties.LabeledBy="{Binding ElementName=WidthLabel,Mode=OneTime}"/>
-						<Label Name="HeightLabel" Grid.Column="2" Target="{Binding ElementName=HeightTextBox,Mode=OneTime}" Content="Height" />
-						<local:DoubleUpDownControl x:Name="HeightTextBox" Grid.Column="3" Value="{Binding Height}" IsEnabled="{Binding Property.CanWrite,Mode=OneTime}" AutomationProperties.LabeledBy="{Binding ElementName=HeightLabel,Mode=OneTime}"/>
-					</Grid>
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition Width="Auto" />
+                            <ColumnDefinition Width="*" />
+                            <ColumnDefinition Width="Auto" />
+                            <ColumnDefinition Width="*" />
+                        </Grid.ColumnDefinitions>
+                        <Label Grid.Column="0" Name="WidthLabel" Target="{Binding ElementName=WidthTextBox,Mode=OneTime}" Content="Width" />
+                        <local:DoubleUpDownControl x:Name="WidthTextBox" Grid.Column="1" Value="{Binding Width}" IsEnabled="{Binding Property.CanWrite,Mode=OneTime}" AutomationProperties.LabeledBy="{Binding ElementName=WidthLabel,Mode=OneTime}" />
+                        <Label Name="HeightLabel" Grid.Column="2" Target="{Binding ElementName=HeightTextBox,Mode=OneTime}" Content="Height" />
+                        <local:DoubleUpDownControl x:Name="HeightTextBox" Grid.Column="3" Value="{Binding Height}" IsEnabled="{Binding Property.CanWrite,Mode=OneTime}" AutomationProperties.LabeledBy="{Binding ElementName=HeightLabel,Mode=OneTime}" />
+                    </Grid>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+
+	<Style TargetType="local:RatioEditorControl">
+		<Setter Property="Template">
+			<Setter.Value>
+				<ControlTemplate TargetType="local:RatioEditorControl">
+					<local:TextBoxEx x:Name="RatioTextBox" AutomationProperties.Name="{Binding Property.Name,Mode=OneTime}" Text="{Binding ValueString}" IsEnabled="{Binding Property.CanWrite,Mode=OneTime}" VerticalContentAlignment="Center" />
 				</ControlTemplate>
 			</Setter.Value>
 		</Setter>
diff --git a/Xamarin.PropertyEditing.Windows/Xamarin.PropertyEditing.Windows.csproj b/Xamarin.PropertyEditing.Windows/Xamarin.PropertyEditing.Windows.csproj
index 6fdaea3..29b4c67 100644
--- a/Xamarin.PropertyEditing.Windows/Xamarin.PropertyEditing.Windows.csproj
+++ b/Xamarin.PropertyEditing.Windows/Xamarin.PropertyEditing.Windows.csproj
@@ -130,6 +130,7 @@
     <Compile Include="PropertyMenuItemContainerStyleSelector.cs" />
     <Compile Include="PropertyPresenter.cs" />
     <Compile Include="ShadeEditorControl.cs" />
+    <Compile Include="RatioEditorControl.cs" />
     <Compile Include="SizeEditorControl.cs" />
     <Compile Include="HueEditorControl.cs" />
     <Compile Include="SolidBrushEditorControl.cs" />
diff --git a/Xamarin.PropertyEditing/Controls/FieldValidation.cs b/Xamarin.PropertyEditing/Controls/FieldValidation.cs
deleted file mode 100644
index f229fc9..0000000
--- a/Xamarin.PropertyEditing/Controls/FieldValidation.cs
+++ /dev/null
@@ -1,178 +0,0 @@
-using System;
-using System.Linq;
-
-namespace Xamarin.PropertyEditing
-{
-	public class FieldValidation
-	{
-		public const string DefaultInitialValue = "1";
-		public const double DefaultIntengerIncrementValue = 1;
-		public const double DefaultDecimalIncrementValue = 0.5d;
-
-		public const int DefaultXcodeMaxRoundDigits = 6;
-		public static char[] Separators = { '/', ':' };
-
-		public static void SetSpinButtonValue (string newValue, int roundDigits, out string finalStringValue, out double finalDecimalValue)
-		{
-			if (CheckIfRatio (newValue)) {
-				finalStringValue = FieldValidation.RoundRatioValue (newValue, roundDigits);
-				finalDecimalValue = newValue.Split (FieldValidation.GetSeparator (newValue))[0].ToEditorDouble ();
-			}
-			else {
-				finalStringValue = FieldValidation.RoundDoubleValue (newValue, roundDigits);
-				finalDecimalValue = newValue.ToEditorDouble ();
-			}
-		}
-
-		public static double CoerceValue (double actualValue, double minimumValue, double maximumValue, bool isWrap)
-		{
-			return (isWrap && actualValue == minimumValue) ? maximumValue : CoerceValue (actualValue, minimumValue, maximumValue);
-		}
-		public static double CoerceValue (double actualValue, double minimumValue, double maximumValue)
-		{
-			return Math.Min (maximumValue, Math.Max (actualValue, minimumValue));
-		}
-
-		public static string FixInitialValue (string value, string defaultValue = DefaultInitialValue)
-		{
-			double parsedValue;
-			if (!value.ToEditorDoubleIfPossible (out parsedValue))
-				value = defaultValue;
-			return string.IsNullOrEmpty (value) ? defaultValue : value;
-		}
-
-		public static string GetInitialOrDefaultValue (string value, double minimumValue, double maximumValue)
-		{
-			return string.IsNullOrEmpty (value) ?
-				FixZeroDoubleValue (Math.Min (Math.Max (minimumValue, 0), maximumValue).ToEditorString ()) :
-				value;
-		}
-
-		public static void SetSpinButtonValue (double newValue, string actualStringValue, int roundDigits, out string finalStringValue, out double finalDecimalValue)
-		{
-			//We round the new value
-			newValue = Math.Round (newValue, roundDigits);
-			//Get the current data to increment
-			double originalValue;
-			//values 0 are writed like 0.0 we need to fix it
-			if (CheckIfRatio (actualStringValue)) {
-				originalValue = actualStringValue.Split (FieldValidation.GetSeparator (actualStringValue))[0].ToEditorDouble ();
-				finalStringValue = string.Concat (FieldValidation.FixZeroDoubleValue (newValue.ToEditorString ()), actualStringValue.Substring (originalValue.ToEditorString ().Length));
-			}
-			else {
-				finalStringValue = FieldValidation.FixZeroDoubleValue (newValue.ToEditorString ());
-			}
-			finalDecimalValue = newValue;
-		}
-
-		public static bool IsNumberLast (string value)
-		{
-			return value.Length > 0 && Char.IsNumber (value.LastOrDefault ());
-		}
-
-		public static string FixZeroDoubleValue (string value)
-		{
-			return value == "0.0" ? "0" : value;
-		}
-
-		public static string RoundDoubleValue (string value, int decimals)
-		{
-			return FixZeroDoubleValue (Math.Round (value.ToEditorDouble (), decimals).ToEditorString ());
-		}
-
-		public static string RoundRatioValue (string value, int decimals)
-		{
-			var separator = FieldValidation.GetSeparator (value);
-			var values = value.Split (separator);
-			return string.Concat (RoundDoubleValue (values[0], decimals), separator, RoundDoubleValue (values[1], decimals));
-		}
-
-		public static bool IsRatio (string value)
-		{
-			if (IsNumberLast (value) && CheckIfRatio (value, ValidationType.Decimal, false)) {
-				var values = value.Split (FieldValidation.GetSeparator (value));
-				return !values[0].ToEditorDouble ().Equals (0) && !values[1].ToEditorDouble ().Equals (0);
-			}
-			return CheckIfNumber (value, ValidationType.Decimal, false);
-		}
-
-		public static bool ValidateDecimal (string finalString, bool allowNegativeValues)
-		{
-			double value;
-			//Checks parsing to number
-			if (!double.TryParse (finalString, out value))
-				return false;
-			//Checks if needs to be possitive value
-			if (!allowNegativeValues && value < 0)
-				return false;
-			//Checks a common validation
-			return CommonValidate (finalString);
-		}
-
-		public static bool ValidateInteger (string finalString, bool allowNegativeValues)
-		{
-			int value;
-			//Checks parsing to number
-			if (!int.TryParse (finalString, out value))
-				return false;
-			//Checks if needs to be possitive value
-			if (!allowNegativeValues && value < 0)
-				return false;
-			//Checks a common validation
-			return CommonValidate (finalString);
-		}
-
-		static bool CommonValidate (string finalString)
-		{
-			return finalString != "-" && !string.IsNullOrEmpty (finalString);
-		}
-
-		public static bool ValidateRatio (string finalString, ValidationType mode, bool allowNegativeValues)
-		{
-			if (CheckIfRatio (finalString, mode, allowNegativeValues) || CheckIfNumber (finalString, mode, allowNegativeValues))
-				return true;
-			return false;
-		}
-
-		public static char GetSeparator (string finalString)
-		{
-			foreach (var separator in Separators) {
-				if (finalString.Contains (separator))
-					return separator;
-			}
-			return default (char);
-		}
-
-		public static bool CheckIfRatio (string value)
-		{
-			return CheckIfRatio (value, ValidationType.Decimal, false);
-		}
-
-		public static bool CheckIfRatio (string finalString, ValidationType mode, bool allowNegativeValues)
-		{
-			foreach (var separator in Separators) {
-				var parts = finalString.Split (new[] { separator });
-				if (parts.Length == 2) {
-					bool parsed = true;
-
-					if (!CheckIfNumber (parts[0], mode, allowNegativeValues))
-						parsed = false;
-
-					if (!String.IsNullOrEmpty (parts[1]) && !CheckIfNumber (parts[1], mode, allowNegativeValues))
-						parsed = false;
-
-					if (parsed)
-						return true;
-				}
-			}
-			return false;
-		}
-
-		public static bool CheckIfNumber (string finalString, ValidationType mode, bool allowNegativeValues)
-		{
-			return mode == ValidationType.Decimal ?
-				ValidateDecimal (finalString, allowNegativeValues) :
-				ValidateInteger (finalString, allowNegativeValues);
-		}
-	}
-}
diff --git a/Xamarin.PropertyEditing/Drawing/CommonRatio.cs b/Xamarin.PropertyEditing/Drawing/CommonRatio.cs
new file mode 100644
index 0000000..b847a77
--- /dev/null
+++ b/Xamarin.PropertyEditing/Drawing/CommonRatio.cs
@@ -0,0 +1,105 @@
+using System;
+
+namespace Xamarin.PropertyEditing.Drawing
+{
+	/// <summary>
+	/// Struct to hold Ratio values
+	/// </summary>
+	[Serializable]
+	public struct CommonRatio : IEquatable<CommonRatio>
+	{
+		/// <param name="numerator">The ratio numerator value.</param>
+		/// <param name="denominator">The ratio denominator value.</param>
+		/// <param name="ratioSeparator">The ratio separator character, '/' or ':'.</param>
+		public CommonRatio (double numerator = 1.0f, double denominator = 1.0f, char ratioSeparator = ':')
+		{
+			this.numerator = numerator;
+			this.denominator = denominator;
+			this.ratioSeparator = ratioSeparator;
+		}
+
+		// Normal values like 1, 200, 400 would be stored as:
+		// Numerator = 100, Denominator = 1
+		//
+		// Ratio values such as 1:3 or 5/6 would be stored as
+		// Numerator = 1, Denominator = 3 etc.
+		public double numerator;
+		public double Numerator {
+			get {
+				if (this.numerator <= 0.0f) {
+					this.numerator = 1; // Default
+				}
+				return this.numerator;
+			}
+			set { this.numerator = value; }
+		}
+
+		public double denominator;
+		public double Denominator {
+			get {
+				if (this.denominator <= 0.0f) {
+					this.denominator = 1; // Default
+				}
+				return this.denominator;
+			}
+			set { this.denominator = value; }
+		}
+
+		public double Value => Numerator / Denominator;
+
+		// This can be either '/' or ':'
+		char ratioSeparator;
+		public char RatioSeparator {
+			get {
+				if (this.ratioSeparator == '\0') {
+					this.ratioSeparator = ':'; // Default
+				}
+				return this.ratioSeparator;
+			}
+			set {
+				this.ratioSeparator = value;
+			}
+		}
+
+		public bool IsRatio => !Denominator.Equals (1.0f);
+
+		public string StringValue => string.Format ("{0}{1}{2}", Numerator, RatioSeparator, Denominator);
+
+		public static bool operator == (CommonRatio left, CommonRatio right)
+		{
+			return Equals (left, right);
+		}
+
+		public static bool operator != (CommonRatio left, CommonRatio right)
+		{
+			return !Equals (left, right);
+		}
+
+		public override bool Equals (object obj)
+		{
+			if (obj == null) 
+				return false;
+			if (!(obj is CommonRatio)) 
+				return false;
+			return Equals ((CommonRatio)obj);
+		}
+
+		public bool Equals (CommonRatio other)
+		{
+			return Numerator.Equals (other.Numerator)
+				            && Denominator.Equals (other.Denominator)
+				            && RatioSeparator.Equals (other.RatioSeparator);
+		}
+
+		public override int GetHashCode ()
+		{
+			var hashCode = 3571; //TODO May need better primes
+			unchecked {
+				hashCode = hashCode * -7919 + Numerator.GetHashCode ();
+				hashCode = hashCode * -7919 + Denominator.GetHashCode ();
+				hashCode = hashCode * -7919 + RatioSeparator.GetHashCode ();
+			}
+			return hashCode;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing/Properties/Resources.Designer.cs b/Xamarin.PropertyEditing/Properties/Resources.Designer.cs
index a6d0394..3d1d708 100644
--- a/Xamarin.PropertyEditing/Properties/Resources.Designer.cs
+++ b/Xamarin.PropertyEditing/Properties/Resources.Designer.cs
@@ -10,48 +10,35 @@
 
 namespace Xamarin.PropertyEditing.Properties {
     using System;
+    using System.Reflection;
     
     
-    /// <summary>
-    ///   A strongly-typed resource class, for looking up localized strings, etc.
-    /// </summary>
-    // This class was auto-generated by the StronglyTypedResourceBuilder
-    // class via a tool like ResGen or Visual Studio.
-    // To add or remove a member, edit your .ResX file then rerun ResGen
-    // with the /str option, or rebuild your VS project.
-    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "15.0.0.0")]
-    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
-    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "4.0.0.0")]
+    [System.Diagnostics.DebuggerNonUserCodeAttribute()]
+    [System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
     public class Resources {
         
-        private static global::System.Resources.ResourceManager resourceMan;
+        private static System.Resources.ResourceManager resourceMan;
         
-        private static global::System.Globalization.CultureInfo resourceCulture;
+        private static System.Globalization.CultureInfo resourceCulture;
         
-        [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        [System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
         internal Resources() {
         }
         
-        /// <summary>
-        ///   Returns the cached ResourceManager instance used by this class.
-        /// </summary>
-        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
-        public static global::System.Resources.ResourceManager ResourceManager {
+        [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Advanced)]
+        public static System.Resources.ResourceManager ResourceManager {
             get {
-                if (object.ReferenceEquals(resourceMan, null)) {
-                    global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("Xamarin.PropertyEditing.Properties.Resources", typeof(Resources).Assembly);
+                if (object.Equals(null, resourceMan)) {
+                    System.Resources.ResourceManager temp = new System.Resources.ResourceManager("Xamarin.PropertyEditing.Properties.Resources", typeof(Resources).Assembly);
                     resourceMan = temp;
                 }
                 return resourceMan;
             }
         }
         
-        /// <summary>
-        ///   Overrides the current thread's CurrentUICulture property for all
-        ///   resource lookups using this strongly typed resource class.
-        /// </summary>
-        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
-        public static global::System.Globalization.CultureInfo Culture {
+        [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Advanced)]
+        public static System.Globalization.CultureInfo Culture {
             get {
                 return resourceCulture;
             }
@@ -60,1146 +47,771 @@ namespace Xamarin.PropertyEditing.Properties {
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Add value converter….
-        /// </summary>
-        public static string AddValueConverterEllipsis {
+        public static string Alpha {
             get {
-                return ResourceManager.GetString("AddValueConverterEllipsis", resourceCulture);
+                return ResourceManager.GetString("Alpha", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Add Value Converter.
-        /// </summary>
-        public static string AddValueConverterTitle {
+        public static string AlphaInitial {
             get {
-                return ResourceManager.GetString("AddValueConverterTitle", resourceCulture);
+                return ResourceManager.GetString("AlphaInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Alpha.
-        /// </summary>
-        public static string Alpha {
+        public static string Black {
             get {
-                return ResourceManager.GetString("Alpha", resourceCulture);
+                return ResourceManager.GetString("Black", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to A.
-        /// </summary>
-        public static string AlphaInitial {
+        public static string BlackInitial {
             get {
-                return ResourceManager.GetString("AlphaInitial", resourceCulture);
+                return ResourceManager.GetString("BlackInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Application.
-        /// </summary>
-        public static string Application {
+        public static string Blue {
             get {
-                return ResourceManager.GetString("Application", resourceCulture);
+                return ResourceManager.GetString("Blue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Apply to all.
-        /// </summary>
-        public static string ApplyToAll {
+        public static string BlueInitial {
             get {
-                return ResourceManager.GetString("ApplyToAll", resourceCulture);
+                return ResourceManager.GetString("BlueInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Binding.
-        /// </summary>
-        public static string Binding {
+        public static string Brightness {
             get {
-                return ResourceManager.GetString("Binding", resourceCulture);
+                return ResourceManager.GetString("Brightness", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Binding type.
-        /// </summary>
-        public static string BindingType {
+        public static string BrightnessInitial {
             get {
-                return ResourceManager.GetString("BindingType", resourceCulture);
+                return ResourceManager.GetString("BrightnessInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Black.
-        /// </summary>
-        public static string Black {
+        public static string CMYK {
             get {
-                return ResourceManager.GetString("Black", resourceCulture);
+                return ResourceManager.GetString("CMYK", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to K.
-        /// </summary>
-        public static string BlackInitial {
+        public static string ColorSpace {
             get {
-                return ResourceManager.GetString("BlackInitial", resourceCulture);
+                return ResourceManager.GetString("ColorSpace", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Blue.
-        /// </summary>
-        public static string Blue {
+        public static string CurrentColor {
             get {
-                return ResourceManager.GetString("Blue", resourceCulture);
+                return ResourceManager.GetString("CurrentColor", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to B.
-        /// </summary>
-        public static string BlueInitial {
+        public static string Cyan {
             get {
-                return ResourceManager.GetString("BlueInitial", resourceCulture);
+                return ResourceManager.GetString("Cyan", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Brightness.
-        /// </summary>
-        public static string Brightness {
+        public static string CyanInitial {
             get {
-                return ResourceManager.GetString("Brightness", resourceCulture);
+                return ResourceManager.GetString("CyanInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to B.
-        /// </summary>
-        public static string BrightnessInitial {
+        public static string CyanMagentaYellowBlack {
             get {
-                return ResourceManager.GetString("BrightnessInitial", resourceCulture);
+                return ResourceManager.GetString("CyanMagentaYellowBlack", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Cancel.
-        /// </summary>
-        public static string Cancel {
+        public static string ConvertToLocalValue {
             get {
-                return ResourceManager.GetString("Cancel", resourceCulture);
+                return ResourceManager.GetString("ConvertToLocalValue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to CMYK.
-        /// </summary>
-        public static string CMYK {
+        public static string CustomExpressionEllipsis {
             get {
-                return ResourceManager.GetString("CMYK", resourceCulture);
+                return ResourceManager.GetString("CustomExpressionEllipsis", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Collection Editor: {0}.
-        /// </summary>
-        public static string CollectionEditorTitle {
+        public static string EventHandlersSelectedElement {
             get {
-                return ResourceManager.GetString("CollectionEditorTitle", resourceCulture);
+                return ResourceManager.GetString("EventHandlersSelectedElement", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to (Collection).
-        /// </summary>
-        public static string CollectionValue {
+        public static string Events {
             get {
-                return ResourceManager.GetString("CollectionValue", resourceCulture);
+                return ResourceManager.GetString("Events", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Editor.
-        /// </summary>
-        public static string ColorEditorTabLabel {
+        public static string Green {
             get {
-                return ResourceManager.GetString("ColorEditorTabLabel", resourceCulture);
+                return ResourceManager.GetString("Green", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Color space.
-        /// </summary>
-        public static string ColorSpace {
+        public static string GreenInitial {
             get {
-                return ResourceManager.GetString("ColorSpace", resourceCulture);
+                return ResourceManager.GetString("GreenInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Convert to Local Value.
-        /// </summary>
-        public static string ConvertToLocalValue {
+        public static string HexValue {
             get {
-                return ResourceManager.GetString("ConvertToLocalValue", resourceCulture);
+                return ResourceManager.GetString("HexValue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Convert to new resource….
-        /// </summary>
-        public static string ConvertToNewResourceEllipsis {
+        public static string HLS {
             get {
-                return ResourceManager.GetString("ConvertToNewResourceEllipsis", resourceCulture);
+                return ResourceManager.GetString("HLS", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Create New Binding….
-        /// </summary>
-        public static string CreateDataBindingMenuItem {
+        public static string HSB {
             get {
-                return ResourceManager.GetString("CreateDataBindingMenuItem", resourceCulture);
+                return ResourceManager.GetString("HSB", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Create Data Binding for {0}.
-        /// </summary>
-        public static string CreateDataBindingTitle {
+        public static string Hue {
             get {
-                return ResourceManager.GetString("CreateDataBindingTitle", resourceCulture);
+                return ResourceManager.GetString("Hue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Create {0} Resource.
-        /// </summary>
-        public static string CreateResourceTitle {
+        public static string HueInitial {
             get {
-                return ResourceManager.GetString("CreateResourceTitle", resourceCulture);
+                return ResourceManager.GetString("HueInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Current color.
-        /// </summary>
-        public static string CurrentColor {
+        public static string HueLightnessSaturation {
             get {
-                return ResourceManager.GetString("CurrentColor", resourceCulture);
+                return ResourceManager.GetString("HueLightnessSaturation", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Custom.
-        /// </summary>
-        public static string Custom {
+        public static string HueSaturationBrightness {
             get {
-                return ResourceManager.GetString("Custom", resourceCulture);
+                return ResourceManager.GetString("HueSaturationBrightness", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Custom expression.
-        /// </summary>
-        public static string CustomExpression {
+        public static string InitialColor {
             get {
-                return ResourceManager.GetString("CustomExpression", resourceCulture);
+                return ResourceManager.GetString("InitialColor", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Custom Expression….
-        /// </summary>
-        public static string CustomExpressionEllipsis {
+        public static string LastColor {
             get {
-                return ResourceManager.GetString("CustomExpressionEllipsis", resourceCulture);
+                return ResourceManager.GetString("LastColor", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Cyan.
-        /// </summary>
-        public static string Cyan {
+        public static string Lightness {
             get {
-                return ResourceManager.GetString("Cyan", resourceCulture);
+                return ResourceManager.GetString("Lightness", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to C.
-        /// </summary>
-        public static string CyanInitial {
+        public static string LightnessInitial {
             get {
-                return ResourceManager.GetString("CyanInitial", resourceCulture);
+                return ResourceManager.GetString("LightnessInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Cyan / Magenta / Yellow / Black.
-        /// </summary>
-        public static string CyanMagentaYellowBlack {
+        public static string Magenta {
             get {
-                return ResourceManager.GetString("CyanMagentaYellowBlack", resourceCulture);
+                return ResourceManager.GetString("Magenta", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Default.
-        /// </summary>
-        public static string Default {
+        public static string MagentaInitial {
             get {
-                return ResourceManager.GetString("Default", resourceCulture);
+                return ResourceManager.GetString("MagentaInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Define in.
-        /// </summary>
-        public static string DefineIn {
+        public static string MultipleObjectsSelected {
             get {
-                return ResourceManager.GetString("DefineIn", resourceCulture);
+                return ResourceManager.GetString("MultipleObjectsSelected", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to ….
-        /// </summary>
-        public static string Ellipsis {
+        public static string MultipleTypesSelected {
             get {
-                return ResourceManager.GetString("Ellipsis", resourceCulture);
+                return ResourceManager.GetString("MultipleTypesSelected", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Event handlers for the selected element.
-        /// </summary>
-        public static string EventHandlersSelectedElement {
+        public static string Name {
             get {
-                return ResourceManager.GetString("EventHandlersSelectedElement", resourceCulture);
+                return ResourceManager.GetString("Name", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Events.
-        /// </summary>
-        public static string Events {
+        public static string NoName {
             get {
-                return ResourceManager.GetString("Events", resourceCulture);
+                return ResourceManager.GetString("NoName", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Something went wrong.
-        /// </summary>
-        public static string GenericErrorMessage {
+        public static string Properties {
             get {
-                return ResourceManager.GetString("GenericErrorMessage", resourceCulture);
+                return ResourceManager.GetString("Properties", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Go to Source.
-        /// </summary>
-        public static string GoToSource {
+        public static string PropertiesSelectedElement {
             get {
-                return ResourceManager.GetString("GoToSource", resourceCulture);
+                return ResourceManager.GetString("PropertiesSelectedElement", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Green.
-        /// </summary>
-        public static string Green {
+        public static string Red {
             get {
-                return ResourceManager.GetString("Green", resourceCulture);
+                return ResourceManager.GetString("Red", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to G.
-        /// </summary>
-        public static string GreenInitial {
+        public static string RedGreenBlue {
             get {
-                return ResourceManager.GetString("GreenInitial", resourceCulture);
+                return ResourceManager.GetString("RedGreenBlue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Hex value.
-        /// </summary>
-        public static string HexValue {
+        public static string RedInitial {
             get {
-                return ResourceManager.GetString("HexValue", resourceCulture);
+                return ResourceManager.GetString("RedInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to HLS.
-        /// </summary>
-        public static string HLS {
+        public static string RGB {
             get {
-                return ResourceManager.GetString("HLS", resourceCulture);
+                return ResourceManager.GetString("RGB", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to HSB.
-        /// </summary>
-        public static string HSB {
+        public static string Saturation {
             get {
-                return ResourceManager.GetString("HSB", resourceCulture);
+                return ResourceManager.GetString("Saturation", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Hue.
-        /// </summary>
-        public static string Hue {
+        public static string SaturationInitial {
             get {
-                return ResourceManager.GetString("Hue", resourceCulture);
+                return ResourceManager.GetString("SaturationInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to H.
-        /// </summary>
-        public static string HueInitial {
+        public static string Reset {
             get {
-                return ResourceManager.GetString("HueInitial", resourceCulture);
+                return ResourceManager.GetString("Reset", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Hue / Lightness / Saturation.
-        /// </summary>
-        public static string HueLightnessSaturation {
+        public static string Type {
             get {
-                return ResourceManager.GetString("HueLightnessSaturation", resourceCulture);
+                return ResourceManager.GetString("Type", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Hue / Saturation / Brightness.
-        /// </summary>
-        public static string HueSaturationBrightness {
+        public static string ViewPropertiesOrEvents {
             get {
-                return ResourceManager.GetString("HueSaturationBrightness", resourceCulture);
+                return ResourceManager.GetString("ViewPropertiesOrEvents", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Inherited.
-        /// </summary>
-        public static string Inherited {
+        public static string Yellow {
             get {
-                return ResourceManager.GetString("Inherited", resourceCulture);
+                return ResourceManager.GetString("Yellow", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Initial color.
-        /// </summary>
-        public static string InitialColor {
+        public static string YellowInitial {
             get {
-                return ResourceManager.GetString("InitialColor", resourceCulture);
+                return ResourceManager.GetString("YellowInitial", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to {0} is an Invalid Value.
-        /// </summary>
-        public static string InvalidValue {
+        public static string NoBrush {
             get {
-                return ResourceManager.GetString("InvalidValue", resourceCulture);
+                return ResourceManager.GetString("NoBrush", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Items.
-        /// </summary>
-        public static string Items {
+        public static string SolidBrush {
             get {
-                return ResourceManager.GetString("Items", resourceCulture);
+                return ResourceManager.GetString("SolidBrush", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Last color.
-        /// </summary>
-        public static string LastColor {
+        public static string ResourceBrush {
             get {
-                return ResourceManager.GetString("LastColor", resourceCulture);
+                return ResourceManager.GetString("ResourceBrush", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Lightness.
-        /// </summary>
-        public static string Lightness {
+        public static string Opacity {
             get {
-                return ResourceManager.GetString("Lightness", resourceCulture);
+                return ResourceManager.GetString("Opacity", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to L.
-        /// </summary>
-        public static string LightnessInitial {
+        public static string ShowAdvancedProperties {
             get {
-                return ResourceManager.GetString("LightnessInitial", resourceCulture);
+                return ResourceManager.GetString("ShowAdvancedProperties", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Local.
-        /// </summary>
-        public static string Local {
+        public static string Cancel {
             get {
-                return ResourceManager.GetString("Local", resourceCulture);
+                return ResourceManager.GetString("Cancel", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Magenta.
-        /// </summary>
-        public static string Magenta {
+        public static string OK {
             get {
-                return ResourceManager.GetString("Magenta", resourceCulture);
+                return ResourceManager.GetString("OK", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to M.
-        /// </summary>
-        public static string MagentaInitial {
+        public static string ShowAllAssemblies {
             get {
-                return ResourceManager.GetString("MagentaInitial", resourceCulture);
+                return ResourceManager.GetString("ShowAllAssemblies", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Amber.
-        /// </summary>
-        public static string MaterialColorAmber {
+        public static string SearchProperties {
             get {
-                return ResourceManager.GetString("MaterialColorAmber", resourceCulture);
+                return ResourceManager.GetString("SearchProperties", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Black and White.
-        /// </summary>
-        public static string MaterialColorBlackAndWhite {
+        public static string New {
             get {
-                return ResourceManager.GetString("MaterialColorBlackAndWhite", resourceCulture);
+                return ResourceManager.GetString("New", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Blue.
-        /// </summary>
-        public static string MaterialColorBlue {
+        public static string SearchObjectsTitle {
             get {
-                return ResourceManager.GetString("MaterialColorBlue", resourceCulture);
+                return ResourceManager.GetString("SearchObjectsTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Blue Grey.
-        /// </summary>
-        public static string MaterialColorBlueGrey {
+        public static string SelectObjectTitle {
             get {
-                return ResourceManager.GetString("MaterialColorBlueGrey", resourceCulture);
+                return ResourceManager.GetString("SelectObjectTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Brown.
-        /// </summary>
-        public static string MaterialColorBrown {
+        public static string CustomExpression {
             get {
-                return ResourceManager.GetString("MaterialColorBrown", resourceCulture);
+                return ResourceManager.GetString("CustomExpression", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Cyan.
-        /// </summary>
-        public static string MaterialColorCyan {
+        public static string ColorEditorTabLabel {
             get {
-                return ResourceManager.GetString("MaterialColorCyan", resourceCulture);
+                return ResourceManager.GetString("ColorEditorTabLabel", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Deep Orange.
-        /// </summary>
-        public static string MaterialColorDeepOrange {
+        public static string SearchResourcesTitle {
             get {
-                return ResourceManager.GetString("MaterialColorDeepOrange", resourceCulture);
+                return ResourceManager.GetString("SearchResourcesTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Deep Purple.
-        /// </summary>
-        public static string MaterialColorDeepPurple {
+        public static string SelectResourceTitle {
             get {
-                return ResourceManager.GetString("MaterialColorDeepPurple", resourceCulture);
+                return ResourceManager.GetString("SelectResourceTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Green.
-        /// </summary>
-        public static string MaterialColorGreen {
+        public static string ShowSystemResources {
             get {
-                return ResourceManager.GetString("MaterialColorGreen", resourceCulture);
+                return ResourceManager.GetString("ShowSystemResources", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Grey.
-        /// </summary>
-        public static string MaterialColorGrey {
+        public static string ResourceEllipsis {
             get {
-                return ResourceManager.GetString("MaterialColorGrey", resourceCulture);
+                return ResourceManager.GetString("ResourceEllipsis", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Indigo.
-        /// </summary>
-        public static string MaterialColorIndigo {
+        public static string Default {
             get {
-                return ResourceManager.GetString("MaterialColorIndigo", resourceCulture);
+                return ResourceManager.GetString("Default", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Light Blue.
-        /// </summary>
-        public static string MaterialColorLightBlue {
+        public static string Inherited {
             get {
-                return ResourceManager.GetString("MaterialColorLightBlue", resourceCulture);
+                return ResourceManager.GetString("Inherited", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Light Green.
-        /// </summary>
-        public static string MaterialColorLightGreen {
+        public static string InvalidValue {
             get {
-                return ResourceManager.GetString("MaterialColorLightGreen", resourceCulture);
+                return ResourceManager.GetString("InvalidValue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Lime.
-        /// </summary>
-        public static string MaterialColorLime {
+        public static string Local {
             get {
-                return ResourceManager.GetString("MaterialColorLime", resourceCulture);
+                return ResourceManager.GetString("Local", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Orange.
-        /// </summary>
-        public static string MaterialColorOrange {
+        public static string Unset {
             get {
-                return ResourceManager.GetString("MaterialColorOrange", resourceCulture);
+                return ResourceManager.GetString("Unset", resourceCulture);
+            }
+        }
+        
+        public static string MaterialColorRed {
+            get {
+                return ResourceManager.GetString("MaterialColorRed", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Pink.
-        /// </summary>
         public static string MaterialColorPink {
             get {
                 return ResourceManager.GetString("MaterialColorPink", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Purple.
-        /// </summary>
         public static string MaterialColorPurple {
             get {
                 return ResourceManager.GetString("MaterialColorPurple", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Red.
-        /// </summary>
-        public static string MaterialColorRed {
+        public static string MaterialColorDeepPurple {
             get {
-                return ResourceManager.GetString("MaterialColorRed", resourceCulture);
+                return ResourceManager.GetString("MaterialColorDeepPurple", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Teal.
-        /// </summary>
-        public static string MaterialColorTeal {
+        public static string MaterialColorIndigo {
             get {
-                return ResourceManager.GetString("MaterialColorTeal", resourceCulture);
+                return ResourceManager.GetString("MaterialColorIndigo", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Yellow.
-        /// </summary>
-        public static string MaterialColorYellow {
+        public static string MaterialColorBlue {
             get {
-                return ResourceManager.GetString("MaterialColorYellow", resourceCulture);
+                return ResourceManager.GetString("MaterialColorBlue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Material Design Colors.
-        /// </summary>
-        public static string MaterialDesignColorBrush {
+        public static string MaterialColorLightBlue {
             get {
-                return ResourceManager.GetString("MaterialDesignColorBrush", resourceCulture);
+                return ResourceManager.GetString("MaterialColorLightBlue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Move item down.
-        /// </summary>
-        public static string MoveItemDown {
+        public static string MaterialColorCyan {
             get {
-                return ResourceManager.GetString("MoveItemDown", resourceCulture);
+                return ResourceManager.GetString("MaterialColorCyan", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Move item up.
-        /// </summary>
-        public static string MoveItemUp {
+        public static string MaterialColorTeal {
             get {
-                return ResourceManager.GetString("MoveItemUp", resourceCulture);
+                return ResourceManager.GetString("MaterialColorTeal", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to {0} objects selected.
-        /// </summary>
-        public static string MultipleObjectsSelected {
+        public static string MaterialColorGreen {
             get {
-                return ResourceManager.GetString("MultipleObjectsSelected", resourceCulture);
+                return ResourceManager.GetString("MaterialColorGreen", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to {0} types selected.
-        /// </summary>
-        public static string MultipleTypesSelected {
+        public static string MaterialColorLightGreen {
             get {
-                return ResourceManager.GetString("MultipleTypesSelected", resourceCulture);
+                return ResourceManager.GetString("MaterialColorLightGreen", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Name.
-        /// </summary>
-        public static string Name {
+        public static string MaterialColorLime {
             get {
-                return ResourceManager.GetString("Name", resourceCulture);
+                return ResourceManager.GetString("MaterialColorLime", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to New.
-        /// </summary>
-        public static string New {
+        public static string MaterialColorYellow {
             get {
-                return ResourceManager.GetString("New", resourceCulture);
+                return ResourceManager.GetString("MaterialColorYellow", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to No brush.
-        /// </summary>
-        public static string NoBrush {
+        public static string MaterialColorAmber {
             get {
-                return ResourceManager.GetString("NoBrush", resourceCulture);
+                return ResourceManager.GetString("MaterialColorAmber", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to &lt;No Name&gt;.
-        /// </summary>
-        public static string NoName {
+        public static string MaterialColorOrange {
             get {
-                return ResourceManager.GetString("NoName", resourceCulture);
+                return ResourceManager.GetString("MaterialColorOrange", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to No preview available.
-        /// </summary>
-        public static string NoPreviewAvailable {
+        public static string MaterialColorDeepOrange {
             get {
-                return ResourceManager.GetString("NoPreviewAvailable", resourceCulture);
+                return ResourceManager.GetString("MaterialColorDeepOrange", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to No value converter.
-        /// </summary>
-        public static string NoValueConverter {
+        public static string MaterialColorBrown {
             get {
-                return ResourceManager.GetString("NoValueConverter", resourceCulture);
+                return ResourceManager.GetString("MaterialColorBrown", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to OK.
-        /// </summary>
-        public static string OK {
+        public static string MaterialColorGrey {
             get {
-                return ResourceManager.GetString("OK", resourceCulture);
+                return ResourceManager.GetString("MaterialColorGrey", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Opacity.
-        /// </summary>
-        public static string Opacity {
+        public static string MaterialColorBlueGrey {
             get {
-                return ResourceManager.GetString("Opacity", resourceCulture);
+                return ResourceManager.GetString("MaterialColorBlueGrey", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to &lt;Other type…&gt;.
-        /// </summary>
-        public static string OtherTypeAction {
+        public static string MaterialDesignColorBrush {
             get {
-                return ResourceManager.GetString("OtherTypeAction", resourceCulture);
+                return ResourceManager.GetString("MaterialDesignColorBrush", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Path.
-        /// </summary>
-        public static string Path {
+        public static string MaterialColorBlackAndWhite {
             get {
-                return ResourceManager.GetString("Path", resourceCulture);
+                return ResourceManager.GetString("MaterialColorBlackAndWhite", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Properties.
-        /// </summary>
-        public static string Properties {
+        public static string White {
             get {
-                return ResourceManager.GetString("Properties", resourceCulture);
+                return ResourceManager.GetString("White", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Properties for the selected element.
-        /// </summary>
-        public static string PropertiesSelectedElement {
+        public static string NoPreviewAvailable {
             get {
-                return ResourceManager.GetString("PropertiesSelectedElement", resourceCulture);
+                return ResourceManager.GetString("NoPreviewAvailable", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Red.
-        /// </summary>
-        public static string Red {
+        public static string Resource {
             get {
-                return ResourceManager.GetString("Red", resourceCulture);
+                return ResourceManager.GetString("Resource", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Red / Green/ Blue.
-        /// </summary>
-        public static string RedGreenBlue {
+        public static string ResourceWithName {
             get {
-                return ResourceManager.GetString("RedGreenBlue", resourceCulture);
+                return ResourceManager.GetString("ResourceWithName", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to R.
-        /// </summary>
-        public static string RedInitial {
+        public static string Binding {
             get {
-                return ResourceManager.GetString("RedInitial", resourceCulture);
+                return ResourceManager.GetString("Binding", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Remove item.
-        /// </summary>
-        public static string RemoveItem {
+        public static string GoToSource {
             get {
-                return ResourceManager.GetString("RemoveItem", resourceCulture);
+                return ResourceManager.GetString("GoToSource", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Reset.
-        /// </summary>
-        public static string Reset {
+        public static string CollectionValue {
             get {
-                return ResourceManager.GetString("Reset", resourceCulture);
+                return ResourceManager.GetString("CollectionValue", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Resource.
-        /// </summary>
-        public static string Resource {
+        public static string Ellipsis {
             get {
-                return ResourceManager.GetString("Resource", resourceCulture);
+                return ResourceManager.GetString("Ellipsis", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Brush from resource.
-        /// </summary>
-        public static string ResourceBrush {
+        public static string OtherTypeAction {
             get {
-                return ResourceManager.GetString("ResourceBrush", resourceCulture);
+                return ResourceManager.GetString("OtherTypeAction", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Resource dictionary.
-        /// </summary>
-        public static string ResourceDictionary {
+        public static string Items {
             get {
-                return ResourceManager.GetString("ResourceDictionary", resourceCulture);
+                return ResourceManager.GetString("Items", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Resource….
-        /// </summary>
-        public static string ResourceEllipsis {
+        public static string CollectionEditorTitle {
             get {
-                return ResourceManager.GetString("ResourceEllipsis", resourceCulture);
+                return ResourceManager.GetString("CollectionEditorTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Name.
-        /// </summary>
-        public static string ResourceNameLabel {
+        public static string MoveItemDown {
             get {
-                return ResourceManager.GetString("ResourceNameLabel", resourceCulture);
+                return ResourceManager.GetString("MoveItemDown", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Resources.
-        /// </summary>
-        public static string ResourcePlural {
+        public static string MoveItemUp {
             get {
-                return ResourceManager.GetString("ResourcePlural", resourceCulture);
+                return ResourceManager.GetString("MoveItemUp", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Resource ({0}).
-        /// </summary>
-        public static string ResourceWithName {
+        public static string RemoveItem {
             get {
-                return ResourceManager.GetString("ResourceWithName", resourceCulture);
+                return ResourceManager.GetString("RemoveItem", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to RGB.
-        /// </summary>
-        public static string RGB {
+        public static string GenericErrorMessage {
             get {
-                return ResourceManager.GetString("RGB", resourceCulture);
+                return ResourceManager.GetString("GenericErrorMessage", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Saturation.
-        /// </summary>
-        public static string Saturation {
+        public static string DefineIn {
             get {
-                return ResourceManager.GetString("Saturation", resourceCulture);
+                return ResourceManager.GetString("DefineIn", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to S.
-        /// </summary>
-        public static string SaturationInitial {
+        public static string Application {
             get {
-                return ResourceManager.GetString("SaturationInitial", resourceCulture);
+                return ResourceManager.GetString("Application", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Search Objects.
-        /// </summary>
-        public static string SearchObjectsTitle {
+        public static string ApplyToAll {
             get {
-                return ResourceManager.GetString("SearchObjectsTitle", resourceCulture);
+                return ResourceManager.GetString("ApplyToAll", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Search properties.
-        /// </summary>
-        public static string SearchProperties {
+        public static string ThisDocument {
             get {
-                return ResourceManager.GetString("SearchProperties", resourceCulture);
+                return ResourceManager.GetString("ThisDocument", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Search Resources.
-        /// </summary>
-        public static string SearchResourcesTitle {
+        public static string ConvertToNewResourceEllipsis {
             get {
-                return ResourceManager.GetString("SearchResourcesTitle", resourceCulture);
+                return ResourceManager.GetString("ConvertToNewResourceEllipsis", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Select Object.
-        /// </summary>
-        public static string SelectObjectTitle {
+        public static string CreateResourceTitle {
             get {
-                return ResourceManager.GetString("SelectObjectTitle", resourceCulture);
+                return ResourceManager.GetString("CreateResourceTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Select Resource.
-        /// </summary>
-        public static string SelectResourceTitle {
+        public static string ResourceNameLabel {
             get {
-                return ResourceManager.GetString("SelectResourceTitle", resourceCulture);
+                return ResourceManager.GetString("ResourceNameLabel", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Show advanced properties.
-        /// </summary>
-        public static string ShowAdvancedProperties {
+        public static string ResourceDictionary {
             get {
-                return ResourceManager.GetString("ShowAdvancedProperties", resourceCulture);
+                return ResourceManager.GetString("ResourceDictionary", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to _Show all assemblies.
-        /// </summary>
-        public static string ShowAllAssemblies {
+        public static string CreateDataBindingMenuItem {
             get {
-                return ResourceManager.GetString("ShowAllAssemblies", resourceCulture);
+                return ResourceManager.GetString("CreateDataBindingMenuItem", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to _Show system resources.
-        /// </summary>
-        public static string ShowSystemResources {
+        public static string AddValueConverterEllipsis {
             get {
-                return ResourceManager.GetString("ShowSystemResources", resourceCulture);
+                return ResourceManager.GetString("AddValueConverterEllipsis", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Solid color brush.
-        /// </summary>
-        public static string SolidBrush {
+        public static string AddValueConverterTitle {
             get {
-                return ResourceManager.GetString("SolidBrush", resourceCulture);
+                return ResourceManager.GetString("AddValueConverterTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to This document.
-        /// </summary>
-        public static string ThisDocument {
+        public static string NoValueConverter {
             get {
-                return ResourceManager.GetString("ThisDocument", resourceCulture);
+                return ResourceManager.GetString("NoValueConverter", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Type.
-        /// </summary>
-        public static string Type {
+        public static string ValueConverterName {
             get {
-                return ResourceManager.GetString("Type", resourceCulture);
+                return ResourceManager.GetString("ValueConverterName", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Unset.
-        /// </summary>
-        public static string Unset {
+        public static string CreateDataBindingTitle {
             get {
-                return ResourceManager.GetString("Unset", resourceCulture);
+                return ResourceManager.GetString("CreateDataBindingTitle", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Value converter name.
-        /// </summary>
-        public static string ValueConverterName {
+        public static string BindingType {
             get {
-                return ResourceManager.GetString("ValueConverterName", resourceCulture);
+                return ResourceManager.GetString("BindingType", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to View properties or events.
-        /// </summary>
-        public static string ViewPropertiesOrEvents {
+        public static string Path {
             get {
-                return ResourceManager.GetString("ViewPropertiesOrEvents", resourceCulture);
+                return ResourceManager.GetString("Path", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to White.
-        /// </summary>
-        public static string White {
+        public static string ResourcePlural {
             get {
-                return ResourceManager.GetString("White", resourceCulture);
+                return ResourceManager.GetString("ResourcePlural", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Yellow.
-        /// </summary>
-        public static string Yellow {
+        public static string Custom {
             get {
-                return ResourceManager.GetString("Yellow", resourceCulture);
+                return ResourceManager.GetString("Custom", resourceCulture);
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Y.
-        /// </summary>
-        public static string YellowInitial {
+        public static string InvalidRatio {
             get {
-                return ResourceManager.GetString("YellowInitial", resourceCulture);
+                return ResourceManager.GetString("InvalidRatio", resourceCulture);
             }
         }
     }
diff --git a/Xamarin.PropertyEditing/Properties/Resources.resx b/Xamarin.PropertyEditing/Properties/Resources.resx
index f9798a8..ebaf050 100644
--- a/Xamarin.PropertyEditing/Properties/Resources.resx
+++ b/Xamarin.PropertyEditing/Properties/Resources.resx
@@ -545,4 +545,7 @@
   <data name="Custom" xml:space="preserve">
     <value>Custom</value>
   </data>
+  <data name="InvalidRatio" xml:space="preserve">
+    <value>Invalid Ratio</value>
+  </data>  
 </root>
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing/ViewModels/PropertiesViewModel.cs b/Xamarin.PropertyEditing/ViewModels/PropertiesViewModel.cs
index 6338908..ba97690 100644
--- a/Xamarin.PropertyEditing/ViewModels/PropertiesViewModel.cs
+++ b/Xamarin.PropertyEditing/ViewModels/PropertiesViewModel.cs
@@ -498,6 +498,7 @@ namespace Xamarin.PropertyEditing.ViewModels
 			{ typeof(BindingSource), (tp,p,e) => new PropertyViewModel<BindingSource> (tp, p, e) },
 			{ typeof(Resource), (tp,p,e) => new PropertyViewModel<Resource> (tp, p, e) },
 			{ typeof(object), (tp,p,e) => new ObjectPropertyViewModel (tp, p, e) },
+			{ typeof(CommonRatio), (tp, p, e) => new RatioViewModel (tp, p, e) },
 		};
 	}
 }
diff --git a/Xamarin.PropertyEditing/ViewModels/RatioViewModel.cs b/Xamarin.PropertyEditing/ViewModels/RatioViewModel.cs
new file mode 100644
index 0000000..9c16d20
--- /dev/null
+++ b/Xamarin.PropertyEditing/ViewModels/RatioViewModel.cs
@@ -0,0 +1,153 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+using Xamarin.PropertyEditing.Drawing;
+
+namespace Xamarin.PropertyEditing.ViewModels
+{
+	internal class RatioViewModel
+		: PropertyViewModel<CommonRatio>
+	{
+		public double Numerator
+		{
+			get { return Value.Numerator; }
+			set {
+				if (Value.Numerator.Equals (value))
+					return;
+
+				Value = new CommonRatio (value, Value.Denominator, Value.RatioSeparator);
+			}
+		}
+
+		public double Denominator
+		{
+			get { return Value.Denominator; }
+
+			set {
+				if (Value.Denominator.Equals (value))
+					return;
+
+				Value = new CommonRatio (Value.Numerator, value, Value.RatioSeparator);
+			}
+		}
+
+		public char RatioSeparator {
+			get { return Value.RatioSeparator; }
+
+			set {
+				if (Value.RatioSeparator.Equals (value))
+					return;
+
+				Value = new CommonRatio (Value.Numerator, Value.Denominator, value);
+			}
+		}
+
+		internal void ValueChanged (string stringValue, int caretPosition, int selectionLength, double incrementValue)
+		{
+			var separator = GetSeparator (stringValue);
+			SetRatioFromString (stringValue);
+
+			var newNumerator = Value.Numerator + incrementValue;
+			if (newNumerator < 1)
+				newNumerator = 1;
+
+			var newDenominator = Value.Denominator + incrementValue;
+			if (newDenominator < 1)
+				newDenominator = 1;
+
+			// Full selection, increment both
+			if (selectionLength == stringValue.Length) {
+				// Increment both values.
+				Value = new CommonRatio (newNumerator, newDenominator, separator);
+			} else {
+				// Only Increment numerator 
+				Value = new CommonRatio (newNumerator, Value.Denominator, separator);
+			}
+		}
+
+		public string ValueString
+		{
+			get { return Value.StringValue; }
+			set {
+				if (Value.StringValue.Equals (value))
+					return;
+
+				SetRatioFromString (value);
+			}
+		}
+
+		public static char[] Separators = { ':', '/' };
+		public static char[] SplitSeparators = { ':', '/', ' ' };
+
+		public RatioViewModel (TargetPlatform platform, IPropertyInfo property, IEnumerable<IObjectEditor> editors)
+			: base (platform, property, editors)
+		{
+		}
+
+		protected override void OnValueChanged ()
+		{
+			base.OnValueChanged ();
+			OnPropertyChanged (nameof (Numerator));
+			OnPropertyChanged (nameof (Denominator));
+			OnPropertyChanged (nameof (RatioSeparator));
+			OnPropertyChanged (nameof (ValueString));
+		}
+
+		private void SetRatioFromString (string value)
+		{
+			bool parsed = true;
+			var parts = value.Split (SplitSeparators, StringSplitOptions.RemoveEmptyEntries);
+				double numerator = 0f;
+			if (parts.Length == 2) { // We have a potential ratio, let's make sure
+				if (!IsDouble (parts[0], out numerator))
+					parsed = false;
+				double denominator = 0f;
+				if (!String.IsNullOrEmpty (parts[1]) && !IsDouble (parts[1], out denominator))
+					parsed = false;
+
+				if (parsed) {
+					Value = new CommonRatio (numerator, denominator, GetSeparator (value));
+				}
+			} else if (parts.Length == 1) { // We have a potential whole number, let's make sure
+				if (!IsDouble (parts[0], out numerator)) {
+					parsed = false;
+				}
+				if (parsed) {
+					Value = new CommonRatio (numerator, 1, GetSeparator (value));
+				}
+			}
+
+			if (!parsed) {
+				SetError (string.Format (Properties.Resources.InvalidRatio, value));
+			}
+		}
+
+		private char GetSeparator (string finalString)
+		{
+			var index = finalString.IndexOfAny (Separators);
+			if (index != -1)
+				return finalString[index];
+			else 
+				return ':';
+		}
+
+		private bool IsDouble (string stringValue, out double value)
+		{
+			//Checks parsing to number
+			if (!double.TryParse (stringValue, out value))
+				return false;
+					
+			//Checks if needs to be positive value
+			if (value < 0)
+				return false;
+					
+			//Checks a common validation
+			return IsValidInput (stringValue);
+		}
+
+		public static bool IsValidInput (string finalString)
+		{
+			return finalString != "-" && !string.IsNullOrEmpty (finalString);
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj b/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
index 0887558..af46062 100644
--- a/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
+++ b/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
@@ -156,12 +156,13 @@
     <Compile Include="IMutableLookup.cs" />
     <Compile Include="OrderedDictionary.cs" />
     <Compile Include="Controls\ValidationType.cs" />
-    <Compile Include="Controls\FieldValidation.cs" />
     <Compile Include="Controls\StringConversionExtensions.cs" />
     <Compile Include="ViewModels\RectanglePropertyViewModel.cs" />
     <Compile Include="ViewModels\ThicknessPropertyViewModel.cs" />
     <Compile Include="ViewModels\ObjectTreeElement.cs" />
     <Compile Include="ViewModels\TypeSelectorViewModel.cs" />
+    <Compile Include="ViewModels\RatioViewModel.cs" />
+    <Compile Include="Drawing\CommonRatio.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Themes\BaseThemeManager.cs" />