Merge branch 'master' into managed-file-dialog

samples/ControlCatalog/MainView.xaml

@@ -6,10 +6,13 @@
         Foreground="{DynamicResource ThemeForegroundBrush}"
         FontSize="{DynamicResource FontSizeNormal}">
   <Grid>
-    <ComboBox x:Name="Themes" SelectedIndex="0" Width="100" Margin="8" HorizontalAlignment="Right" VerticalAlignment="Bottom">
-      <ComboBoxItem>Light</ComboBoxItem>
-      <ComboBoxItem>Dark</ComboBoxItem>
-    </ComboBox>
+    <Grid.Styles>
+        <Style Selector="TextBlock.h2">
+            <Setter Property="TextWrapping" Value="Wrap"/>
+            <Setter Property="MaxWidth" Value="400"/>
+            <Setter Property="HorizontalAlignment" Value="Left"/>
+        </Style>
+    </Grid.Styles>  
     <TabControl Classes="sidebar" Name="Sidebar">
       <TabItem Header="AutoCompleteBox"><pages:AutoCompleteBoxPage/></TabItem>
       <TabItem Header="Border"><pages:BorderPage/></TabItem>
@@ -21,7 +24,12 @@
       <TabItem Header="CheckBox"><pages:CheckBoxPage/></TabItem>
       <TabItem Header="ComboBox"><pages:ComboBoxPage/></TabItem>
       <TabItem Header="ContextMenu"><pages:ContextMenuPage/></TabItem>
-      <TabItem Header="DataGrid"><pages:DataGridPage/></TabItem>
+      <!-- DataGrid is our special snowflake -->  
+      <TabItem Header="DataGrid" 
+               ScrollViewer.VerticalScrollBarVisibility="Disabled"
+               ScrollViewer.HorizontalScrollBarVisibility="Disabled">
+          <pages:DataGridPage/>
+      </TabItem>
       <TabItem Header="DatePicker"><pages:DatePickerPage/></TabItem>
       <TabItem Header="Drag+Drop"><pages:DragAndDropPage/></TabItem>
       <TabItem Header="Expander"><pages:ExpanderPage/></TabItem>
@@ -42,6 +50,12 @@
       <TabItem Header="ToolTip"><pages:ToolTipPage/></TabItem>
       <TabItem Header="TreeView"><pages:TreeViewPage/></TabItem>
       <TabItem Header="Viewbox"><pages:ViewboxPage/></TabItem>
+    <TabControl.Tag>
+        <ComboBox x:Name="Themes" SelectedIndex="0" Width="100" Margin="8" HorizontalAlignment="Right" VerticalAlignment="Bottom">
+            <ComboBoxItem>Light</ComboBoxItem>
+            <ComboBoxItem>Dark</ComboBoxItem>
+        </ComboBox>
+    </TabControl.Tag>
     </TabControl>
   </Grid>
 </UserControl>

samples/ControlCatalog/MainWindow.xaml

@@ -1,4 +1,5 @@
 <Window xmlns="https://github.com/avaloniaui" MinWidth="500" MinHeight="300"
+        Width="1024" Height="800"
         xmlns:pages="clr-namespace:ControlCatalog.Pages"
         Title="Avalonia Control Gallery"
         Icon="/Assets/test_icon.ico"

samples/ControlCatalog/Pages/PointersPage.cs

@@ -69,16 +69,25 @@ namespace ControlCatalog.Pages
         {
             UpdatePointer(e);
             e.Pointer.Capture(this);
+            e.Handled = true;
             base.OnPointerPressed(e);
         }
 
         protected override void OnPointerMoved(PointerEventArgs e)
         {
             UpdatePointer(e);
+            e.Handled = true;
             base.OnPointerMoved(e);
         }
 
         protected override void OnPointerReleased(PointerReleasedEventArgs e)
+        {
+            _pointers.Remove(e.Pointer);
+            e.Handled = true;
+            InvalidateVisual();
+        }
+
+        protected override void OnPointerCaptureLost(PointerCaptureLostEventArgs e)
         {
             _pointers.Remove(e.Pointer);
             InvalidateVisual();

samples/ControlCatalog/Pages/ScreenPage.cs

@@ -22,7 +22,10 @@ namespace ControlCatalog.Pages
         public override void Render(DrawingContext context)
         {
             base.Render(context);
-            Window w = (Window)VisualRoot;
+            if (!(VisualRoot is Window w))
+            {
+                return;                
+            }
             var screens = w.Screens.All;
             var scaling = ((IRenderRoot)w).RenderScaling;
 

samples/ControlCatalog/SideBar.xaml

@@ -24,7 +24,8 @@
                             Name="PART_ScrollViewer"
                             HorizontalScrollBarVisibility="{TemplateBinding (ScrollViewer.HorizontalScrollBarVisibility)}"
                             VerticalScrollBarVisibility="{TemplateBinding (ScrollViewer.VerticalScrollBarVisibility)}"
-                            Background="{TemplateBinding Background}">
+                            Background="{TemplateBinding Background}"
+                            DockPanel.Dock="Left">
                             <ItemsPresenter
                                 Name="PART_ItemsPresenter"                          
                                 Items="{TemplateBinding Items}"
@@ -32,14 +33,19 @@
                                 ItemTemplate="{TemplateBinding ItemTemplate}">
                             </ItemsPresenter>
                         </ScrollViewer>
-                        <ContentPresenter
-                            Name="PART_SelectedContentHost"
-                            Margin="{TemplateBinding Padding}"                           
-                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
-                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
-                            Content="{TemplateBinding SelectedContent}"
-                            ContentTemplate="{TemplateBinding SelectedContentTemplate}">
-                        </ContentPresenter>
+                        <ContentControl Content="{TemplateBinding Tag}" HorizontalContentAlignment="Right" DockPanel.Dock="Bottom"/>
+                        <ScrollViewer
+                            HorizontalScrollBarVisibility="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=SelectedItem.(ScrollViewer.HorizontalScrollBarVisibility)}"
+                            VerticalScrollBarVisibility="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=SelectedItem.(ScrollViewer.VerticalScrollBarVisibility)}">
+                            <ContentPresenter
+                                    Name="PART_SelectedContentHost"
+                                    Margin="{TemplateBinding Padding}"                           
+                                    HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                    VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
+                                    Content="{TemplateBinding SelectedContent}"
+                                    ContentTemplate="{TemplateBinding SelectedContentTemplate}">
+                            </ContentPresenter>
+                        </ScrollViewer>
                     </DockPanel>
                 </Border>
             </ControlTemplate>
@@ -58,6 +64,8 @@
                 <DoubleTransition Property="Opacity" Duration="0:0:0.150"/>
             </Transitions>
         </Setter>
+        <Setter Property="(ScrollViewer.HorizontalScrollBarVisibility)" Value="Auto"/>
+        <Setter Property="(ScrollViewer.VerticalScrollBarVisibility)" Value="Auto"/>
     </Style>
     <Style Selector="TabControl.sidebar > TabItem:pointerover">
         <Setter Property="Opacity" Value="1"/>

src/Avalonia.Controls/Mixins/ContentControlMixin.cs

@@ -150,6 +150,7 @@ namespace Avalonia.Controls.Mixins
                 if (oldValue is IControl child)
                 {
                     logicalChildren.Remove(child);
+                    ((ISetInheritanceParent)child).SetParent(child.Parent);
                 }
 
                 child = newValue as IControl;

src/Avalonia.Controls/Presenters/ContentPresenter.cs

@@ -229,7 +229,6 @@ namespace Avalonia.Controls.Presenters
                 if (oldChild != null)
                 {
                     VisualChildren.Remove(oldChild);
-                    ((ISetInheritanceParent)oldChild).SetParent(oldChild.Parent);
                 }
 
                 if (oldChild?.Parent == this)
@@ -238,7 +237,7 @@ namespace Avalonia.Controls.Presenters
                     // template.
                     LogicalChildren.Remove(oldChild);
                 }
-                else
+                else if (TemplatedParent != null)
                 {
                     // If we're in a ContentControl's template then invoke ChildChanging to let
                     // ContentControlMixin handle removing the logical child.
@@ -249,6 +248,10 @@ namespace Avalonia.Controls.Presenters
                         newChild,
                         BindingPriority.LocalValue));
                 }
+                else if (oldChild != null)
+                {
+                    ((ISetInheritanceParent)oldChild).SetParent(oldChild.Parent);
+                }
             }
 
             // Set the DataContext if the data isn't a control.
@@ -434,6 +437,7 @@ namespace Avalonia.Controls.Presenters
             {
                 VisualChildren.Remove(Child);
                 LogicalChildren.Remove(Child);
+                ((ISetInheritanceParent)Child).SetParent(Child.Parent);
                 Child = null;
                 _dataTemplate = null;
             }

tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_InTemplate.cs

@@ -1,7 +1,11 @@
 // 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;
+using System.Collections.Generic;
+using System.ComponentModel;
 using System.Linq;
+using System.Reactive.Linq;
 using Avalonia.Controls.Presenters;
 using Avalonia.Controls.Templates;
 using Avalonia.Data;
@@ -256,7 +260,6 @@ namespace Avalonia.Controls.UnitTests.Presenters
             Assert.IsType<Canvas>(target.Child);
         }
 
-
         [Fact]
         public void Should_Not_Bind_Old_Child_To_New_DataContext()
         {
@@ -281,6 +284,34 @@ namespace Avalonia.Controls.UnitTests.Presenters
             target.Content = 42;
         }
 
+        [Fact]
+        public void Should_Not_Bind_Child_To_Wrong_DataContext_When_Removing()
+        {
+            // Test for issue #2823
+            var canvas = new Canvas();
+            var (target, host) = CreateTarget();
+            var viewModel = new TestViewModel { Content = "foo" };
+            var dataContexts = new List<object>();
+
+            target.Bind(ContentPresenter.ContentProperty, (IBinding)new TemplateBinding(ContentControl.ContentProperty));
+            canvas.GetObservable(ContentPresenter.DataContextProperty).Subscribe(x => dataContexts.Add(x));
+
+            host.DataTemplates.Add(new FuncDataTemplate<string>((_, __) => canvas));
+            host.Bind(ContentControl.ContentProperty, new Binding(nameof(TestViewModel.Content)));
+            host.DataContext = viewModel;
+
+            Assert.Same(canvas, target.Child);
+
+            viewModel.Content = 42;
+
+            Assert.Equal(new object[]
+            {
+                null,
+                "foo",
+                null,
+            }, dataContexts);
+        }
+
         [Fact]
         public void Should_Set_InheritanceParent_Even_When_LogicalParent_Is_Already_Set()
         {
@@ -333,5 +364,25 @@ namespace Avalonia.Controls.UnitTests.Presenters
         {
             public IControl Child { get; set; }
         }
+
+        private class TestViewModel : INotifyPropertyChanged
+        {
+            private object _content;
+
+            public object Content
+            {
+                get => _content;
+                set
+                {
+                    if (_content != value)
+                    {
+                        _content = value;
+                        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Content)));
+                    }
+                }
+            }
+
+            public event PropertyChangedEventHandler PropertyChanged;
+        }
     }
 }

tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_Standalone.cs

@@ -251,5 +251,21 @@ namespace Avalonia.Controls.UnitTests.Presenters
 
             target.Content = 42;
         }
+
+        [Fact]
+        public void Should_Reset_InheritanceParent_When_Child_Removed()
+        {
+            var logicalParent = new Canvas();
+            var child = new TextBlock();
+            var target = new ContentPresenter();
+            var root = new TestRoot(target);
+
+            ((ISetLogicalParent)child).SetParent(logicalParent);
+            target.Content = child;
+            target.Content = null;
+
+            // InheritanceParent is exposed via StylingParent.
+            Assert.Same(logicalParent, ((IStyledElement)child).StylingParent);
+        }
     }
 }

tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_Unrooted.cs

@@ -98,5 +98,22 @@ namespace Avalonia.Controls.UnitTests.Presenters
             target.ApplyTemplate();
             Assert.IsType<Decorator>(target.Child);
         }
+
+        [Fact]
+        public void Should_Reset_InheritanceParent_When_Child_Removed()
+        {
+            var logicalParent = new Canvas();
+            var child = new TextBlock();
+            var target = new ContentPresenter();
+
+            ((ISetLogicalParent)child).SetParent(logicalParent);
+            target.Content = child;
+            target.UpdateChild();
+            target.Content = null;
+            target.UpdateChild();
+
+            // InheritanceParent is exposed via StylingParent.
+            Assert.Same(logicalParent, ((IStyledElement)child).StylingParent);
+        }
     }
 }