Merge pull request #4471 from MahApps/fix/4468_splitview_bindings

Change SplitView to ContentControl

Author: punker76

src/MahApps.Metro.Samples/MahApps.Metro.Demo/ExampleViews/SplitViewExamples.xaml

@@ -117,13 +117,15 @@
             </mah:SplitView.Pane>
 
             <Grid Background="CornflowerBlue">
-                <TextBlock Margin="20"
-                           HorizontalAlignment="Center"
-                           VerticalAlignment="Center"
-                           FontSize="20"
-                           Foreground="White"
-                           Text="This is the main content area and should be blue"
-                           TextWrapping="Wrap" />
+                <StackPanel>
+                    <TextBlock Margin="10"
+                               HorizontalAlignment="Stretch"
+                               VerticalAlignment="Stretch"
+                               FontSize="20"
+                               Foreground="Black"
+                               Text="{Binding ElementName=sliderTest, Path=Value, Mode=OneWay, FallbackValue=0}" />
+                    <Slider x:Name="sliderTest" Margin="10" Minimum="0" Maximum="100" Value="42" />
+                </StackPanel>
             </Grid>
 
         </mah:SplitView>

src/MahApps.Metro/Controls/SplitView/SplitView.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections;
+using System.ComponentModel;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
@@ -33,7 +34,7 @@ namespace MahApps.Metro.Controls
     [TemplateVisualState(Name = "OpenCompactOverlayRight", GroupName = "DisplayModeStates")]
     [ContentProperty(nameof(Content))]
     [StyleTypedProperty(Property = nameof(ResizeThumbStyle), StyleTargetType = typeof(MetroThumb))]
-    public class SplitView : Control
+    public class SplitView : ContentControl
     {
         private Rectangle? lightDismissLayer;
         private RectangleGeometry? paneClipRectangle;
@@ -69,23 +70,6 @@ public double CompactPaneLength
             set => this.SetValue(CompactPaneLengthProperty, value);
         }
 
-        /// <summary>Identifies the <see cref="Content"/> dependency property.</summary>
-        public static readonly DependencyProperty ContentProperty
-            = DependencyProperty.Register(nameof(Content),
-                                          typeof(UIElement),
-                                          typeof(SplitView),
-                                          new PropertyMetadata(null));
-
-        /// <summary>
-        ///     Gets or sets the contents of the main panel of a <see cref="SplitView" />.
-        /// </summary>
-        /// <returns>The contents of the main panel of a <see cref="SplitView" />. The default is null.</returns>
-        public UIElement? Content
-        {
-            get => (UIElement?)this.GetValue(ContentProperty);
-            set => this.SetValue(ContentProperty, value);
-        }
-
         /// <summary>Identifies the <see cref="DisplayMode"/> dependency property.</summary>
         public static readonly DependencyProperty DisplayModeProperty
             = DependencyProperty.Register(nameof(DisplayMode),
@@ -337,20 +321,87 @@ public Style? ResizeThumbStyle
         /// <summary>Identifies the <see cref="Pane"/> dependency property.</summary>
         public static readonly DependencyProperty PaneProperty
             = DependencyProperty.Register(nameof(Pane),
-                                          typeof(UIElement),
+                                          typeof(object),
                                           typeof(SplitView),
-                                          new PropertyMetadata(null, UpdateLogicalChild));
+                                          new FrameworkPropertyMetadata(
+                                              null,
+                                              new PropertyChangedCallback(OnPaneChanged)));
 
         /// <summary>
         ///     Gets or sets the contents of the pane of a <see cref="SplitView" />.
         /// </summary>
         /// <returns>The contents of the pane of a <see cref="SplitView" />. The default is null.</returns>
-        public UIElement? Pane
+        [Bindable(true), Category("Content")]
+        public object? Pane
         {
-            get => (UIElement?)this.GetValue(PaneProperty);
+            get => this.GetValue(PaneProperty);
             set => this.SetValue(PaneProperty, value);
         }
 
+        /// <summary>
+        ///     Called when PaneProperty is invalidated
+        /// </summary>
+        private static void OnPaneChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            SplitView splitView = (SplitView)d;
+
+            splitView.OnPaneChanged(e.OldValue, e.NewValue);
+        }
+
+        /// <summary>
+        ///     This method is invoked when the Header property changes.
+        /// </summary>
+        /// <param name="oldPane">The old value of the Header property.</param>
+        /// <param name="newPane">The new value of the Header property.</param>
+        protected virtual void OnPaneChanged(object oldPane, object newPane)
+        {
+            this.RemoveLogicalChild(oldPane);
+            this.AddLogicalChild(newPane);
+
+            if (newPane is FrameworkElement frameworkElement)
+            {
+                frameworkElement.DataContext = this.DataContext;
+            }
+        }
+
+        /// <summary>Identifies the <see cref="PaneTemplate"/> dependency property.</summary>
+        public static readonly DependencyProperty PaneTemplateProperty
+            = DependencyProperty.Register(
+                nameof(PaneTemplate),
+                typeof(DataTemplate),
+                typeof(SplitView),
+                new FrameworkPropertyMetadata(
+                    null,
+                    new PropertyChangedCallback(OnPaneTemplateChanged)));
+
+        /// <summary>
+        ///     PaneTemplate is the template used to display the <seealso cref="Pane"/>.
+        /// </summary>
+        [Bindable(true), Category("Content")]
+        public DataTemplate? PaneTemplate
+        {
+            get => (DataTemplate?)this.GetValue(PaneTemplateProperty);
+            set => this.SetValue(PaneTemplateProperty, value);
+        }
+
+        /// <summary>
+        ///     Called when PaneTemplateProperty is invalidated on "d."
+        /// </summary>
+        private static void OnPaneTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            SplitView ctrl = (SplitView)d;
+            ctrl.OnPaneTemplateChanged((DataTemplate?)e.OldValue, (DataTemplate?)e.NewValue);
+        }
+
+        /// <summary>
+        ///     This method is invoked when the PaneTemplate property changes.
+        /// </summary>
+        /// <param name="oldPaneTemplate">The old value of the PaneTemplate property.</param>
+        /// <param name="newPaneTemplate">The new value of the PaneTemplate property.</param>
+        protected virtual void OnPaneTemplateChanged(DataTemplate? oldPaneTemplate, DataTemplate? newPaneTemplate)
+        {
+        }
+
         /// <summary>Identifies the <see cref="PaneBackground"/> dependency property.</summary>
         public static readonly DependencyProperty PaneBackgroundProperty
             = DependencyProperty.Register(nameof(PaneBackground),
@@ -504,25 +555,6 @@ private void ResizingThumb_DragDelta(object sender, System.Windows.Controls.Prim
             this.SetCurrentValue(OpenPaneLengthProperty, this.PanePlacement == SplitViewPanePlacement.Left ? this.OpenPaneLength + e.HorizontalChange : this.OpenPaneLength - e.HorizontalChange);
         }
 
-        private static void UpdateLogicalChild(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e)
-        {
-            if (dependencyObject is not SplitView splitView)
-            {
-                return;
-            }
-
-            if (e.OldValue is FrameworkElement oldChild)
-            {
-                splitView.RemoveLogicalChild(oldChild);
-            }
-
-            if (e.NewValue is FrameworkElement newChild)
-            {
-                splitView.AddLogicalChild(newChild);
-                newChild.DataContext = splitView.DataContext;
-            }
-        }
-
         /// <inheritdoc />
         protected override IEnumerator LogicalChildren
         {