Merge pull request #760 from mono/leak-fix-attempt

Leak fix attempt

5 files changed, 41 insertions, 12 deletions

diff --git a/Xwt/Xwt.Backends/BackendHost.cs b/Xwt/Xwt.Backends/BackendHost.cs
index 14458a6b..025ee8ab 100644
--- a/Xwt/Xwt.Backends/BackendHost.cs
+++ b/Xwt/Xwt.Backends/BackendHost.cs
@@ -59,7 +59,7 @@ namespace Xwt.Backends
 	/// <summary>
 	/// The BackendHost is the link between an Xwt frontend and a toolkit backend.
 	/// </summary>
-	public class BackendHost: EventHost
+	public class BackendHost: EventHost, IDisposable
 	{
 		IBackend backend;
 		bool usingCustomBackend;
@@ -131,8 +131,10 @@ namespace Xwt.Backends
 		/// </summary>
 		protected virtual void OnBackendCreated ()
 		{
-			foreach (var ev in DefaultEnabledEvents)
+			foreach (var ev in DefaultEnabledEvents) {
+				enabledEvents.Add (ev);
 				Backend.EnableEvent (ev);
+			}
 		}
 		
 		/// <summary>
@@ -171,12 +173,15 @@ namespace Xwt.Backends
 			}
 		}
 
+		List<object> enabledEvents = new List<object> ();
+
 		/// <summary>
 		/// Enables an event with the specified identifier.
 		/// </summary>
 		/// <param name="eventId">Event identifier (must be a valid event enum value).</param>
 		protected override void OnEnableEvent (object eventId)
 		{
+			enabledEvents.Add (eventId);
 			Backend.EnableEvent (eventId);
 		}
 
@@ -186,8 +191,16 @@ namespace Xwt.Backends
 		/// <param name="eventId">Event identifier (must be a valid event enum value).</param>
 		protected override void OnDisableEvent (object eventId)
 		{
+			enabledEvents.Remove (eventId);
 			Backend.DisableEvent (eventId);
 		}
+
+		public void Dispose ()
+		{
+			foreach (var ev in enabledEvents)
+				Backend.DisableEvent (ev);
+			enabledEvents.Clear ();
+		}
 	}
 }
 
diff --git a/Xwt/Xwt/Paned.cs b/Xwt/Xwt/Paned.cs
index dce339df..37cc7641 100755
--- a/Xwt/Xwt/Paned.cs
+++ b/Xwt/Xwt/Paned.cs
@@ -44,17 +44,18 @@ namespace Xwt
 			{
 				IPanedBackend b = (IPanedBackend) base.OnCreateBackend ();
 				
-				// We always want to listen this event because we use it
-				// to reallocate the children
-				if (!EngineBackend.HandlesSizeNegotiation)
-					b.EnableEvent (PanedEvent.PositionChanged);
-				
 				return b;
 			}
 		
 			protected override void OnBackendCreated ()
 			{
 				Backend.Initialize (Parent.direction);
+
+				// We always want to listen this event because we use it
+				// to reallocate the children
+				if (!EngineBackend.HandlesSizeNegotiation)
+					OnEnableEvent (PanedEvent.PositionChanged);
+
 				base.OnBackendCreated ();
 			}
 				
diff --git a/Xwt/Xwt/Toolkit.cs b/Xwt/Xwt/Toolkit.cs
index 4ecd1f44..f087e5b1 100644
--- a/Xwt/Xwt/Toolkit.cs
+++ b/Xwt/Xwt/Toolkit.cs
@@ -830,7 +830,7 @@ namespace Xwt
 
 	class NativeWindowFrame: WindowFrame
 	{
-		public NativeWindowFrame (IWindowFrameBackend backend)
+		public NativeWindowFrame (IWindowFrameBackend backend) : base (owned: false)
 		{
 			BackendHost.SetCustomBackend (backend);
 		}
diff --git a/Xwt/Xwt/WindowFrame.cs b/Xwt/Xwt/WindowFrame.cs
index 890b9dc4..9ae1f4c9 100644
--- a/Xwt/Xwt/WindowFrame.cs
+++ b/Xwt/Xwt/WindowFrame.cs
@@ -74,6 +74,7 @@ namespace Xwt
 		bool pendingReallocation;
 		Image icon;
 		WindowFrame transientFor;
+		protected bool Owned { get; }
 		
 		protected class WindowBackendHost: BackendHost<WindowFrame,IWindowFrameBackend>, IWindowFrameEventSink
 		{
@@ -83,7 +84,8 @@ namespace Xwt
 				base.OnBackendCreated ();
 				Parent.location = Backend.Bounds.Location;
 				Parent.size = Backend.Bounds.Size;
-				Backend.EnableEvent (WindowFrameEvent.BoundsChanged);
+				if (Parent.Owned)
+					OnEnableEvent (WindowFrameEvent.BoundsChanged);
 			}
 			
 			public void OnBoundsChanged (Rectangle bounds)
@@ -120,7 +122,12 @@ namespace Xwt
 			MapEvent (WindowFrameEvent.Closed, typeof(WindowFrame), "OnClosed");
 		}
 
-		public WindowFrame ()
+		protected WindowFrame (bool owned)
+		{
+			Owned = owned;
+		}
+
+		public WindowFrame () : this (owned: true)
 		{
 			if (!(base.BackendHost is WindowBackendHost))
 				throw new InvalidOperationException ("CreateBackendHost for WindowFrame did not return a WindowBackendHost instance");
@@ -137,7 +144,7 @@ namespace Xwt
 			
 			// Don't dispose the backend if this object is being finalized
 			// The backend has to handle the finalizing on its own
-			if (disposing && BackendHost.BackendCreated)
+			if (disposing && BackendHost.BackendCreated && Owned)
 				Backend.Dispose ();
 		}
 		
@@ -403,7 +410,9 @@ namespace Xwt
 		internal virtual Rectangle BackendBounds {
 			get {
 				BackendHost.EnsureBackendLoaded ();
-				return new Rectangle (location, size);
+				if (Owned)
+					return new Rectangle (location, size);
+				return Backend.Bounds;
 			}
 			set {
 				size = value.Size;
diff --git a/Xwt/Xwt/XwtComponent.cs b/Xwt/Xwt/XwtComponent.cs
index 4b5974e5..fa935d12 100755
--- a/Xwt/Xwt/XwtComponent.cs
+++ b/Xwt/Xwt/XwtComponent.cs
@@ -74,6 +74,12 @@ namespace Xwt
 			get { return backendHost.Backend; }
 		}
 
+		protected override void Dispose(bool release_all)
+		{
+			backendHost.Dispose ();
+			base.Dispose(release_all);
+		}
+
 		/// <summary>
 		/// Gets or sets the name of this component.
 		/// </summary>