diff --git a/src/Avalonia.Controls/Mixins/ContentControlMixin.cs b/src/Avalonia.Controls/Mixins/ContentControlMixin.cs index 95193c0432..e4204bd27f 100644 --- a/src/Avalonia.Controls/Mixins/ContentControlMixin.cs +++ b/src/Avalonia.Controls/Mixins/ContentControlMixin.cs @@ -3,6 +3,7 @@ using System; using System.Linq; +using System.Reactive.Disposables; using System.Runtime.CompilerServices; using Avalonia.Collections; using Avalonia.Controls.Presenters; @@ -75,6 +76,12 @@ namespace Avalonia.Controls.Mixins null, presenter.GetValue(ContentPresenter.ChildProperty)); + if (subscriptions.Value.TryGetValue(sender, out IDisposable previousSubscription)) + { + subscription = new CompositeDisposable(previousSubscription, subscription); + subscriptions.Value.Remove(sender); + } + subscriptions.Value.Add(sender, subscription); } } diff --git a/tests/Avalonia.Controls.UnitTests/Mixins/ContentControlMixinTests.cs b/tests/Avalonia.Controls.UnitTests/Mixins/ContentControlMixinTests.cs new file mode 100644 index 0000000000..f06553411c --- /dev/null +++ b/tests/Avalonia.Controls.UnitTests/Mixins/ContentControlMixinTests.cs @@ -0,0 +1,106 @@ +// Copyright (c) The Avalonia Project. All rights reserved. +// Licensed under the MIT license. See licence.md file in the project root for full license information. + +using System.Collections.Generic; +using System.Linq; +using Avalonia.Collections; +using Avalonia.Controls.Mixins; +using Avalonia.Controls.Presenters; +using Avalonia.Controls.Primitives; +using Avalonia.Controls.Templates; +using Avalonia.LogicalTree; +using Moq; +using Xunit; + +namespace Avalonia.Controls.UnitTests.Mixins +{ + public class ContentControlMixinTests + { + [Fact] + public void Multiple_Mixin_Usages_Should_Not_Throw() + { + var target = new TestControl() + { + Template = new FuncControlTemplate(_ => new Panel + { + Children = + { + new ContentPresenter { Name = "Content_1_Presenter" }, + new ContentPresenter { Name = "Content_2_Presenter" } + } + }) + }; + + var ex = Record.Exception(() => target.ApplyTemplate()); + + Assert.Null(ex); + } + + [Fact] + public void Replacing_Template_Releases_Events() + { + var p1 = new ContentPresenter { Name = "Content_1_Presenter" }; + var p2 = new ContentPresenter { Name = "Content_2_Presenter" }; + var target = new TestControl + { + Template = new FuncControlTemplate(_ => new Panel + { + Children = + { + p1, + p2 + } + }) + }; + target.ApplyTemplate(); + + Control tc; + + p1.Content = tc = new Control(); + p1.UpdateChild(); + Assert.Contains(tc, target.GetLogicalChildren()); + + p2.Content = tc = new Control(); + p2.UpdateChild(); + Assert.Contains(tc, target.GetLogicalChildren()); + + target.Template = null; + + p1.Content = tc = new Control(); + p1.UpdateChild(); + Assert.DoesNotContain(tc, target.GetLogicalChildren()); + + p2.Content = tc = new Control(); + p2.UpdateChild(); + Assert.DoesNotContain(tc, target.GetLogicalChildren()); + + } + + private class TestControl : TemplatedControl + { + public static readonly StyledProperty Content1Property = + AvaloniaProperty.Register(nameof(Content1)); + + public static readonly StyledProperty Content2Property = + AvaloniaProperty.Register(nameof(Content2)); + + static TestControl() + { + ContentControlMixin.Attach(Content1Property, x => x.LogicalChildren, "Content_1_Presenter"); + ContentControlMixin.Attach(Content2Property, x => x.LogicalChildren, "Content_2_Presenter"); + } + + public object Content1 + { + get { return GetValue(Content1Property); } + set { SetValue(Content1Property, value); } + } + + public object Content2 + { + get { return GetValue(Content2Property); } + set { SetValue(Content2Property, value); } + } + } + } +}