Remove VisualElement finalizer (#918)

* [Controls] Add repo for bugzilla 55365

* Remove finalizer from VisualElement

* Remove unused using directive

* Removing test for 44074

* Update docs

diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla55365.cs b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla55365.cs
new file mode 100644 (file)
index 0000000..1ab99a2
--- /dev/null
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla55365.cs
@@ -0,0 +1,90 @@
+using System;
+using System.Collections.ObjectModel;
+using System.Collections.Specialized;
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+#if UITEST
+using NUnit.Framework;
+
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+       [Preserve(AllMembers = true)]
+       [Issue(IssueTracker.Bugzilla, 55365, "~VisualElement crashes with System.Runtime.InteropServices.COMException", PlatformAffected.UWP)]
+       public class Bugzilla55365 : TestContentPage
+       {
+               readonly StackLayout _itemsPanel = new StackLayout();
+               readonly DataTemplate _itemTemplate = new DataTemplate(CreateBoxView);
+               readonly StackLayout _layout = new StackLayout();
+
+#if UITEST
+               [Test]
+               public void ForcingGCDoesNotCrash()
+               {
+                       RunningApp.WaitForElement("Clear");
+                       RunningApp.Tap("Clear");
+                       RunningApp.Tap("Garbage");
+                       RunningApp.WaitForElement("Success");
+               }
+#endif
+
+               protected override void Init()
+               {
+                       var viewModel = new ObservableCollection<_55365Item>
+                       {
+                               new _55365Item { Subject = 65 }
+                       };
+
+                       viewModel.CollectionChanged += OnCollectionChanged;
+
+                       _itemsPanel.BindingContext = viewModel;
+
+                       foreach (_55365Item item in viewModel)
+                       {
+                               _itemTemplate.SetValue(BindingContextProperty, item);
+                               var view = (View)_itemTemplate.CreateContent();
+                               _itemsPanel.Children.Add(view);
+                       }
+
+                       var clearButton = new Button { Text = "Clear", Command = new Command(o => viewModel.Clear()) };
+                       _layout.Children.Add(clearButton);
+
+                       var collectButton = new Button { Text = "Garbage", Command = new Command(o =>
+                       {
+                               GC.Collect();
+                               GC.WaitForPendingFinalizers();
+                               _layout.Children.Add(new Label {Text = "Success"});
+                       }) };
+                       _layout.Children.Add(collectButton);
+                       _layout.Children.Add(_itemsPanel);
+
+                       Content = _layout;
+               }
+
+               static object CreateBoxView()
+               {
+                       var boxView1 = new BoxView { HeightRequest = 100, Color = new Color(0.55, 0.23, 0.147) };
+                       var setter1 = new Setter { Property = BoxView.ColorProperty, Value = "#FF2879DD" };
+                       var trigger1 = new DataTrigger(typeof(BoxView)) { Binding = new Binding("Subject"), Value = 65 };
+                       trigger1.Setters.Add(setter1);
+                       boxView1.Triggers.Add(trigger1);
+                       return boxView1;
+               }
+
+               void OnCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
+               {
+                       if (e.Action == NotifyCollectionChangedAction.Reset)
+                       {
+                               // reset the list
+                               _itemsPanel.Children.Clear();
+                       }
+               }
+
+               [Preserve(AllMembers = true)]
+               public class _55365Item
+               {
+                       public int Subject { get; set; }
+               }
+       }
+}
\ No newline at end of file

diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
index f602ef6..0d808d2 100644 (file)
--- a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
@@ -279,6 +279,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla53909.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ListViewNRE.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla55745.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Bugzilla55365.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)_Template.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue1028.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue1075.cs" />

diff --git a/Xamarin.Forms.Core.UnitTests/BehaviorTest.cs b/Xamarin.Forms.Core.UnitTests/BehaviorTest.cs
index 9021738..464f973 100644 (file)
--- a/Xamarin.Forms.Core.UnitTests/BehaviorTest.cs
+++ b/Xamarin.Forms.Core.UnitTests/BehaviorTest.cs
@@ -109,42 +109,5 @@ namespace Xamarin.Forms.Core.UnitTests
                        collection.Remove (behavior);
                        Assert.Null (behavior.AssociatedObject);
                }
-
-               [Test]
-               //https://bugzilla.xamarin.com/show_bug.cgi?id=44074
-               public void TestBehaviorsAreDetachedBeforeGarbageCollection()
-               {
-                       WeakReference weakBindable = null;
-
-                       var attachCount = MockBehavior<VisualElement>.AttachCount;
-
-                       int i = 0;
-                       Action create = null;
-                       create = () =>
-                       {
-                               if (i++ < 1024)
-                               {
-                                       create();
-                                       return;
-                               }
-
-                               var bindable = new MockBindable
-                               {
-                                       Behaviors = {
-                                               new MockBehavior<VisualElement> ()
-                                       }
-                               };
-                               weakBindable = new WeakReference(bindable);
-                       };
-
-                       create();
-
-                       GC.Collect();
-                       GC.WaitForPendingFinalizers();
-                       GC.Collect();
-
-                       Assert.False(weakBindable.IsAlive);
-                       Assert.AreEqual(attachCount, MockBehavior<VisualElement>.AttachCount);
-               }
        }
 }
\ No newline at end of file

diff --git a/Xamarin.Forms.Core/VisualElement.cs b/Xamarin.Forms.Core/VisualElement.cs
index 8aba78a..520b06b 100644 (file)
--- a/Xamarin.Forms.Core/VisualElement.cs
+++ b/Xamarin.Forms.Core/VisualElement.cs
@@ -796,18 +796,5 @@ namespace Xamarin.Forms
 
                        public bool Result { get; set; }
                }
-
-               ~VisualElement()
-               {
-                       if (!GetIsDefault(BehaviorsProperty)) {
-                               var behaviors = GetValue(BehaviorsProperty) as AttachedCollection<Behavior>;
-                               behaviors.DetachFrom(this);
-                       }
-
-                       if (!GetIsDefault(TriggersProperty)) {
-                               var triggers = GetValue(TriggersProperty) as AttachedCollection<TriggerBase>;
-                               triggers.DetachFrom(this);
-                       }
-               }
        }
 }
\ No newline at end of file

diff --git a/docs/Xamarin.Forms.Core/Xamarin.Forms/VisualElement.xml b/docs/Xamarin.Forms.Core/Xamarin.Forms/VisualElement.xml
index b5d1f8b..0a11683 100644 (file)
--- a/docs/Xamarin.Forms.Core/Xamarin.Forms/VisualElement.xml
+++ b/docs/Xamarin.Forms.Core/Xamarin.Forms/VisualElement.xml
@@ -352,22 +352,6 @@
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
-    <Member MemberName="Finalize">
-      <MemberSignature Language="C#" Value="~VisualElement ();" />
-      <MemberSignature Language="ILAsm" Value=".method familyhidebysig virtual instance void Finalize() cil managed" />
-      <MemberType>Method</MemberType>
-      <AssemblyInfo>
-        <AssemblyVersion>2.0.0.0</AssemblyVersion>
-      </AssemblyInfo>
-      <ReturnValue>
-        <ReturnType>System.Void</ReturnType>
-      </ReturnValue>
-      <Parameters />
-      <Docs>
-        <summary>Finalizer for visual elements.</summary>
-        <remarks>To be added.</remarks>
-      </Docs>
-    </Member>
     <Member MemberName="Focus">
       <MemberSignature Language="C#" Value="public bool Focus ();" />
       <MemberSignature Language="ILAsm" Value=".method public hidebysig instance bool Focus() cil managed" />