tsai
/
Avalonia
mirror of https://github.com/AvaloniaUI/Avalonia.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

Merge pull request #2413 from AvaloniaUI/fixes/2390-command-leak 

Prevent leaks due to subscriptions to commands
release/0.8.0
danwalmsley 7 years ago
committed by GitHub
parent
edfa04f164 fb6ffce908
commit
f8f4c23597
No known key found for this signature in database GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 172 additions and 32 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 69
      src/Avalonia.Controls/Button.cs
  2. 35
      src/Avalonia.Controls/MenuItem.cs
  3. 46
      tests/Avalonia.Controls.UnitTests/ButtonTests.cs
  4. 54
      tests/Avalonia.Controls.UnitTests/MenuItemTests.cs

69
src/Avalonia.Controls/Button.cs
View File

@ -7,6 +7,7 @@ using System.Windows.Input;
using Avalonia.Data;
using Avalonia.Input;
using Avalonia.Interactivity;
using Avalonia.LogicalTree;
using Avalonia.VisualTree;
namespace Avalonia.Controls
@ -160,6 +161,40 @@ namespace Avalonia.Controls
}
}
/// <inheritdoc/>
protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
{
base.OnDetachedFromVisualTree(e);
if (IsDefault)
{
if (e.Root is IInputElement inputElement)
{
StopListeningForDefault(inputElement);
}
}
}
protected override void OnAttachedToLogicalTree(LogicalTreeAttachmentEventArgs e)
{
base.OnAttachedToLogicalTree(e);
if (Command != null)
{
Command.CanExecuteChanged += CanExecuteChanged;
}
}
protected override void OnDetachedFromLogicalTree(LogicalTreeAttachmentEventArgs e)
{
base.OnDetachedFromLogicalTree(e);
if (Command != null)
{
Command.CanExecuteChanged -= CanExecuteChanged;
}
}
/// <inheritdoc/>
protected override void OnKeyDown(KeyEventArgs e)
{
@ -195,20 +230,6 @@ namespace Avalonia.Controls
}
}
/// <inheritdoc/>
protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
{
base.OnDetachedFromVisualTree(e);
if (IsDefault)
{
if (e.Root is IInputElement inputElement)
{
StopListeningForDefault(inputElement);
}
}
}
/// <summary>
/// Invokes the <see cref="Click"/> event.
/// </summary>
@ -281,17 +302,17 @@ namespace Avalonia.Controls
{
if (e.Sender is Button button)
{
var oldCommand = e.OldValue as ICommand;
var newCommand = e.NewValue as ICommand;
if (oldCommand != null)
{
oldCommand.CanExecuteChanged -= button.CanExecuteChanged;
}
if (newCommand != null)
if (((ILogical)button).IsAttachedToLogicalTree)
{
newCommand.CanExecuteChanged += button.CanExecuteChanged;
if (e.OldValue is ICommand oldCommand)
{
oldCommand.CanExecuteChanged -= button.CanExecuteChanged;
}
if (e.NewValue is ICommand newCommand)
{
newCommand.CanExecuteChanged += button.CanExecuteChanged;
}
}
button.CanExecuteChanged(button, EventArgs.Empty);

35
src/Avalonia.Controls/MenuItem.cs
View File

@ -286,6 +286,26 @@ namespace Avalonia.Controls
return new MenuItemContainerGenerator(this);
}
protected override void OnAttachedToLogicalTree(LogicalTreeAttachmentEventArgs e)
{
base.OnAttachedToLogicalTree(e);
if (Command != null)
{
Command.CanExecuteChanged += CanExecuteChanged;
}
}
protected override void OnDetachedFromLogicalTree(LogicalTreeAttachmentEventArgs e)
{
base.OnDetachedFromLogicalTree(e);
if (Command != null)
{
Command.CanExecuteChanged -= CanExecuteChanged;
}
}
/// <summary>
/// Called when the <see cref="MenuItem"/> is clicked.
/// </summary>
@ -399,14 +419,17 @@ namespace Avalonia.Controls
{
if (e.Sender is MenuItem menuItem)
{
if (e.OldValue is ICommand oldCommand)
if (((ILogical)menuItem).IsAttachedToLogicalTree)
{
oldCommand.CanExecuteChanged -= menuItem.CanExecuteChanged;
}
if (e.OldValue is ICommand oldCommand)
{
oldCommand.CanExecuteChanged -= menuItem.CanExecuteChanged;
}
if (e.NewValue is ICommand newCommand)
{
newCommand.CanExecuteChanged += menuItem.CanExecuteChanged;
if (e.NewValue is ICommand newCommand)
{
newCommand.CanExecuteChanged += menuItem.CanExecuteChanged;
}
}
menuItem.CanExecuteChanged(menuItem, EventArgs.Empty);

46
tests/Avalonia.Controls.UnitTests/ButtonTests.cs
View File

@ -5,6 +5,7 @@ using Avalonia.Input;
using Avalonia.Media;
using Avalonia.Platform;
using Avalonia.Rendering;
using Avalonia.UnitTests;
using Avalonia.VisualTree;
using Moq;
using Xunit;
@ -21,6 +22,7 @@ namespace Avalonia.Controls.UnitTests
{
Command = command,
};
var root = new TestRoot { Child = target };
Assert.False(target.IsEnabled);
command.IsEnabled = true;
@ -215,6 +217,39 @@ namespace Avalonia.Controls.UnitTests
Assert.True(clicked);
}
[Fact]
public void Button_Does_Not_Subscribe_To_Command_CanExecuteChanged_Until_Added_To_Logical_Tree()
{
var command = new TestCommand(true);
var target = new Button
{
Command = command,
};
Assert.Equal(0, command.SubscriptionCount);
}
[Fact]
public void Button_Subscribes_To_Command_CanExecuteChanged_When_Added_To_Logical_Tree()
{
var command = new TestCommand(true);
var target = new Button { Command = command };
var root = new TestRoot { Child = target };
Assert.Equal(1, command.SubscriptionCount);
}
[Fact]
public void Button_Unsubscribes_From_Command_CanExecuteChanged_When_Removed_From_Logical_Tree()
{
var command = new TestCommand(true);
var target = new Button { Command = command };
var root = new TestRoot { Child = target };
root.Child = null;
Assert.Equal(0, command.SubscriptionCount);
}
private class TestButton : Button, IRenderRoot
{
public TestButton()
@ -298,6 +333,7 @@ namespace Avalonia.Controls.UnitTests
private class TestCommand : ICommand
{
private EventHandler _canExecuteChanged;
private bool _enabled;
public TestCommand(bool enabled)
@ -313,12 +349,18 @@ namespace Avalonia.Controls.UnitTests
if (_enabled != value)
{
_enabled = value;
CanExecuteChanged?.Invoke(this, EventArgs.Empty);
_canExecuteChanged?.Invoke(this, EventArgs.Empty);
}
}
}
public event EventHandler CanExecuteChanged;
public int SubscriptionCount { get; private set; }
public event EventHandler CanExecuteChanged
{
add { _canExecuteChanged += value; ++SubscriptionCount; }
remove { _canExecuteChanged -= value; --SubscriptionCount; }
}
public bool CanExecute(object parameter) => _enabled;

54
tests/Avalonia.Controls.UnitTests/MenuItemTests.cs
View File

@ -1,6 +1,8 @@
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Input;
using Avalonia.UnitTests;
using Xunit;
namespace Avalonia.Controls.UnitTests
@ -22,5 +24,57 @@ namespace Avalonia.Controls.UnitTests
Assert.False(target.Focusable);
}
[Fact]
public void MenuItem_Does_Not_Subscribe_To_Command_CanExecuteChanged_Until_Added_To_Logical_Tree()
{
var command = new TestCommand();
var target = new MenuItem
{
Command = command,
};
Assert.Equal(0, command.SubscriptionCount);
}
[Fact]
public void MenuItem_Subscribes_To_Command_CanExecuteChanged_When_Added_To_Logical_Tree()
{
var command = new TestCommand();
var target = new MenuItem { Command = command };
var root = new TestRoot { Child = target };
Assert.Equal(1, command.SubscriptionCount);
}
[Fact]
public void MenuItem_Unsubscribes_From_Command_CanExecuteChanged_When_Removed_From_Logical_Tree()
{
var command = new TestCommand();
var target = new MenuItem { Command = command };
var root = new TestRoot { Child = target };
root.Child = null;
Assert.Equal(0, command.SubscriptionCount);
}
private class TestCommand : ICommand
{
private EventHandler _canExecuteChanged;
public int SubscriptionCount { get; private set; }
public event EventHandler CanExecuteChanged
{
add { _canExecuteChanged += value; ++SubscriptionCount; }
remove { _canExecuteChanged -= value; --SubscriptionCount; }
}
public bool CanExecute(object parameter) => true;
public void Execute(object parameter)
{
}
}
}
}

Write Preview
Loading…
Cancel
Save