Merge pull request #863 from daserge/scrollview-keyb-focus-style-a11y

[WPF] Indicate ScrollView keyboard focus

4 files changed, 96 insertions, 5 deletions

diff --git a/Xwt.WPF/Xwt.WPF.csproj b/Xwt.WPF/Xwt.WPF.csproj
index 719f015c..3d97251b 100644
--- a/Xwt.WPF/Xwt.WPF.csproj
+++ b/Xwt.WPF/Xwt.WPF.csproj
@@ -191,4 +191,10 @@
     <EmbeddedResource Include="icons\remove-16~disabled.png" />

     <EmbeddedResource Include="icons\remove-16~dark~disabled.png" />

   </ItemGroup>

+  <ItemGroup>

+    <Resource Include="Xwt.WPFBackend\ScrollView.xaml">

+      <SubType>Designer</SubType>

+      <Generator>MSBuild:Compile</Generator>

+    </Resource>

+  </ItemGroup>

 </Project>
\ No newline at end of file
diff --git a/Xwt.WPF/Xwt.WPFBackend/CustomScrollViewPort.cs b/Xwt.WPF/Xwt.WPFBackend/CustomScrollViewPort.cs
index fd388ccd..10c4e771 100644
--- a/Xwt.WPF/Xwt.WPFBackend/CustomScrollViewPort.cs
+++ b/Xwt.WPF/Xwt.WPFBackend/CustomScrollViewPort.cs
@@ -37,11 +37,13 @@ namespace Xwt.WPFBackend
 	internal class CustomScrollViewPort
 		: SWC.Panel, IScrollInfo
 	{
-		internal CustomScrollViewPort (object widget, ScrollAdjustmentBackend verticalBackend, ScrollAdjustmentBackend horizontalBackend)
+		internal CustomScrollViewPort (object widget, SWC.ScrollViewer scrollOwner, ScrollAdjustmentBackend verticalBackend, ScrollAdjustmentBackend horizontalBackend)
 		{
 			if (widget == null)
 				throw new ArgumentNullException ("widget");
 
+			ScrollOwner = scrollOwner;
+
 			((FrameworkElement)widget).RenderTransform = this.transform;
 
 			if (verticalBackend != null) {
diff --git a/Xwt.WPF/Xwt.WPFBackend/ScrollView.xaml b/Xwt.WPF/Xwt.WPFBackend/ScrollView.xaml
new file mode 100644
index 00000000..6f20769e
--- /dev/null
+++ b/Xwt.WPF/Xwt.WPFBackend/ScrollView.xaml
@@ -0,0 +1,41 @@
+<ResourceDictionary
+	xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+	xmlns:l="clr-namespace:Xwt.WPFBackend;assembly=Xwt.WPF">
+
+    <Style TargetType="{x:Type l:ExScrollViewer}">
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="{x:Type l:ExScrollViewer}">
+                    <Grid>
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition />
+                            <ColumnDefinition Width="Auto" />
+                        </Grid.ColumnDefinitions>
+                        <Grid.RowDefinitions>
+                            <RowDefinition />
+                            <RowDefinition Height="Auto" />
+                        </Grid.RowDefinitions>
+                        <Border x:Name="PART_ScrollContentPresenter"
+                            BorderThickness="{TemplateBinding BorderThickness}" BorderBrush="{TemplateBinding BorderBrush}">
+                            <ScrollContentPresenter />
+                        </Border>
+                        <ScrollBar x:Name="PART_VerticalScrollBar" Grid.Column="1"
+                             Value="{TemplateBinding VerticalOffset}"
+                             Maximum="{TemplateBinding ScrollableHeight}"
+                             ViewportSize="{TemplateBinding ViewportHeight}"
+                             Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}"/>
+                        <ScrollBar x:Name="PART_HorizontalScrollBar"
+                             Orientation="Horizontal"
+                             Grid.Row="1"
+                             Grid.Column="0"
+                             Value="{TemplateBinding HorizontalOffset}"
+                             Maximum="{TemplateBinding ScrollableWidth}"
+                             ViewportSize="{TemplateBinding ViewportWidth}"
+                             Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>
+                    </Grid>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+</ResourceDictionary>
\ No newline at end of file
diff --git a/Xwt.WPF/Xwt.WPFBackend/ScrollViewBackend.cs b/Xwt.WPF/Xwt.WPFBackend/ScrollViewBackend.cs
index 8affbbf4..59133440 100644
--- a/Xwt.WPF/Xwt.WPFBackend/ScrollViewBackend.cs
+++ b/Xwt.WPF/Xwt.WPFBackend/ScrollViewBackend.cs
@@ -26,17 +26,49 @@
 
 using System;
 using Xwt.Backends;
-using Xwt.WPFBackend;
 using System.Windows.Controls;
+using System.Windows.Media;
+using System.Windows;
+using System.Windows.Markup;
 
 namespace Xwt.WPFBackend
 {
 	public class ScrollViewBackend
 		: WidgetBackend, IScrollViewBackend
 	{
-		public ScrollViewBackend()
+		private static readonly ResourceDictionary ScrollViewResourceDictionary;
+		static ScrollViewBackend ()
 		{
-			ScrollViewer = new ExScrollViewer();
+			Uri uri = new Uri ("pack://application:,,,/Xwt.WPF;component/XWT.WPFBackend/ScrollView.xaml");
+			ScrollViewResourceDictionary = (ResourceDictionary) XamlReader.Load (System.Windows.Application.GetResourceStream (uri).Stream);
+		}
+
+		public ScrollViewBackend ()
+		{
+			ScrollViewer = new ExScrollViewer ();
+			ScrollViewer.Resources.MergedDictionaries.Add (ScrollViewResourceDictionary);
+			ScrollViewer.GotKeyboardFocus += ScrollViewer_GotKeyboardFocus;
+			ScrollViewer.LostKeyboardFocus += ScrollViewer_LostKeyboardFocus;
+		}
+
+		Brush previousBrush;
+		Thickness previousBrushThickness;
+		void ScrollViewer_LostKeyboardFocus (object sender, System.Windows.Input.KeyboardFocusChangedEventArgs e)
+		{
+			if (BorderVisible) {
+				ScrollViewer.BorderThickness = previousBrushThickness;
+				ScrollViewer.BorderBrush = previousBrush;
+			}
+		}
+
+		void ScrollViewer_GotKeyboardFocus (object sender, System.Windows.Input.KeyboardFocusChangedEventArgs e)
+		{
+			if (BorderVisible) {
+				previousBrush = ScrollViewer.BorderBrush;
+				previousBrushThickness = ScrollViewer.BorderThickness;
+				ScrollViewer.BorderThickness = new Thickness (1);
+				ScrollViewer.BorderBrush = SystemColors.HighlightBrush;
+			}
 		}
 
 		public ScrollPolicy VerticalScrollPolicy
@@ -122,7 +154,7 @@ namespace Xwt.WPFBackend
 				vscrollControl = vbackend = new ScrollAdjustmentBackend ();
 				hscrollControl = hbackend = new ScrollAdjustmentBackend ();
 			}
-			ScrollViewer.Content = new CustomScrollViewPort (widget.NativeWidget, vbackend, hbackend);
+			ScrollViewer.Content = new CustomScrollViewPort (widget.NativeWidget, ScrollViewer, vbackend, hbackend);
 			ScrollViewer.CanContentScroll = true;
 
 			if (vbackend != null)
@@ -169,6 +201,16 @@ namespace Xwt.WPFBackend
 			}
 		}
 
+		protected override void Dispose (bool disposing)
+		{
+			if (ScrollViewer != null) {
+				ScrollViewer.GotKeyboardFocus -= ScrollViewer_GotKeyboardFocus;
+				ScrollViewer.LostKeyboardFocus -= ScrollViewer_LostKeyboardFocus;
+			}
+
+			base.Dispose (disposing);
+		}
+
 		protected ScrollViewer ScrollViewer
 		{
 			get { return (ScrollViewer) Widget; }