Simplify TemplateBindings

samples/ControlCatalog/SideBar.xaml

@@ -8,7 +8,7 @@
             <TabStrip Name="PART_TabStrip"
                       MemberSelector="{x:Static TabControl.HeaderSelector}"
                       Items="{TemplateBinding Items}"
-                      SelectedIndex="{TemplateBinding Path=SelectedIndex, Mode=TwoWay}">
+                      SelectedIndex="{TemplateBinding SelectedIndex, Mode=TwoWay}">
               <TabStrip.ItemsPanel>
                 <ItemsPanelTemplate>
                   <StackPanel Orientation="Vertical"/>
@@ -20,7 +20,7 @@
                     Margin="8 0 0 0"
                     MemberSelector="{x:Static TabControl.ContentSelector}"
                     Items="{TemplateBinding Items}"
-                    SelectedIndex="{TemplateBinding Path=SelectedIndex}"
+                    SelectedIndex="{TemplateBinding SelectedIndex}"
                     PageTransition="{TemplateBinding PageTransition}"
                     Grid.Row="1"/>
         </DockPanel>

samples/RenderDemo/SideBar.xaml

@@ -9,7 +9,7 @@
             <TabStrip Name="PART_TabStrip"
                       MemberSelector="{x:Static TabControl.HeaderSelector}"
                       Items="{TemplateBinding Items}"
-                      SelectedIndex="{TemplateBinding Path=SelectedIndex, Mode=TwoWay}">
+                      SelectedIndex="{TemplateBinding SelectedIndex, Mode=TwoWay}">
               <TabStrip.ItemsPanel>
                 <ItemsPanelTemplate>
                   <StackPanel Orientation="Vertical"/>
@@ -21,7 +21,7 @@
                     Margin="8 0 0 0"
                     MemberSelector="{x:Static TabControl.ContentSelector}"
                     Items="{TemplateBinding Items}"
-                    SelectedIndex="{TemplateBinding Path=SelectedIndex}"
+                    SelectedIndex="{TemplateBinding SelectedIndex}"
                     PageTransition="{TemplateBinding PageTransition}"
                     Grid.Row="1"/>
         </DockPanel>

src/Avalonia.Themes.Default/AutoCompleteBox.xaml

@@ -16,7 +16,7 @@
                    DataValidationErrors.Errors="{TemplateBinding (DataValidationErrors.Errors)}" />
 
           <Popup Name="PART_Popup"
-                 MinWidth="{TemplateBinding Bounds.Width}"
+                 MinWidth="{Binding Bounds.Width, RelativeSource={RelativeSource TemplatedParent}}"
                  MaxHeight="{TemplateBinding MaxDropDownHeight}"
                  PlacementTarget="{TemplateBinding}"
                  StaysOpen="False">

src/Avalonia.Themes.Default/DropDown.xaml

@@ -32,7 +32,7 @@
             </ToggleButton>
             <Popup Name="PART_Popup"
                    IsOpen="{TemplateBinding IsDropDownOpen, Mode=TwoWay}"
-                   MinWidth="{TemplateBinding Bounds.Width}"
+                   MinWidth="{Binding Bounds.Width, RelativeSource={RelativeSource TemplatedParent}}"
                    MaxHeight="{TemplateBinding MaxDropDownHeight}"
                    PlacementTarget="{TemplateBinding}"
                    StaysOpen="False">

src/Avalonia.Themes.Default/MenuItem.xaml

@@ -45,7 +45,7 @@
             <Popup Name="PART_Popup"
                    PlacementMode="Right"
                    StaysOpen="True"
-                   IsOpen="{TemplateBinding Path=IsSubMenuOpen, Mode=TwoWay}"
+                   IsOpen="{TemplateBinding IsSubMenuOpen, Mode=TwoWay}"
                    ObeyScreenEdges="True">
               <Border Background="{TemplateBinding Background}"
                       BorderBrush="{DynamicResource ThemeBorderMidBrush}"
@@ -92,7 +92,7 @@
               </ContentPresenter.DataTemplates>
             </ContentPresenter>
             <Popup Name="PART_Popup"
-                   IsOpen="{TemplateBinding Path=IsSubMenuOpen, Mode=TwoWay}"
+                   IsOpen="{TemplateBinding IsSubMenuOpen, Mode=TwoWay}"
                    StaysOpen="True" 
                    ObeyScreenEdges="True">
               <Border Background="{TemplateBinding Background}"

src/Avalonia.Themes.Default/ScrollBar.xaml

@@ -16,7 +16,7 @@
                                Grid.Column="1"
                                Minimum="{TemplateBinding Minimum}"
                                Maximum="{TemplateBinding Maximum}"
-                               Value="{TemplateBinding Path=Value, Mode=TwoWay}"
+                               Value="{TemplateBinding Value, Mode=TwoWay}"
                                ViewportSize="{TemplateBinding ViewportSize}"
                                Orientation="{TemplateBinding Orientation}">
                             <Track.DecreaseButton>
@@ -67,7 +67,7 @@
                                Grid.Column="1"
                                Minimum="{TemplateBinding Minimum}"
                                Maximum="{TemplateBinding Maximum}"
-                               Value="{TemplateBinding Path=Value, Mode=TwoWay}"
+                               Value="{TemplateBinding Value, Mode=TwoWay}"
                                ViewportSize="{TemplateBinding ViewportSize}"
                                Orientation="{TemplateBinding Orientation}">
                             <Track.DecreaseButton>

src/Avalonia.Themes.Default/ScrollViewer.xaml

@@ -9,21 +9,21 @@
                                 CanHorizontallyScroll="{TemplateBinding CanHorizontallyScroll}"
                                 CanVerticallyScroll="{TemplateBinding CanVerticallyScroll}"
                                 Content="{TemplateBinding Content}"
-                                Extent="{TemplateBinding Path=Extent, Mode=TwoWay}"
+                                Extent="{TemplateBinding Extent, Mode=TwoWay}"
                                 Margin="{TemplateBinding Padding}"
-                                Offset="{TemplateBinding Path=Offset, Mode=TwoWay}"
-                                Viewport="{TemplateBinding Path=Viewport, Mode=TwoWay}"/>
+                                Offset="{TemplateBinding Offset, Mode=TwoWay}"
+                                Viewport="{TemplateBinding Viewport, Mode=TwoWay}"/>
         <ScrollBar Name="horizontalScrollBar"
                    Orientation="Horizontal"
                    Maximum="{TemplateBinding HorizontalScrollBarMaximum}"
-                   Value="{TemplateBinding Path=HorizontalScrollBarValue, Mode=TwoWay}"
+                   Value="{TemplateBinding HorizontalScrollBarValue, Mode=TwoWay}"
                    ViewportSize="{TemplateBinding HorizontalScrollBarViewportSize}"
                    Visibility="{TemplateBinding HorizontalScrollBarVisibility}"
                    Grid.Row="1"/>
         <ScrollBar Name="verticalScrollBar"
                    Orientation="Vertical"
                    Maximum="{TemplateBinding VerticalScrollBarMaximum}"
-                   Value="{TemplateBinding Path=VerticalScrollBarValue, Mode=TwoWay}"
+                   Value="{TemplateBinding VerticalScrollBarValue, Mode=TwoWay}"
                    ViewportSize="{TemplateBinding VerticalScrollBarViewportSize}"
                    Visibility="{TemplateBinding VerticalScrollBarVisibility}"
                    Grid.Column="1"/>

src/Avalonia.Themes.Default/Slider.xaml

@@ -11,7 +11,7 @@
             <RowDefinition Height="Auto"/>
           </Grid.RowDefinitions>
           <Border Name="TrackBackground" Grid.Row="1" Height="4" Margin="6,0" VerticalAlignment="Center"/>
-          <Track Name="PART_Track" Grid.Row="1">
+          <Track Name="PART_Track" Grid.Row="1" Orientation="Horizontal">
             <Track.DecreaseButton>
                <RepeatButton Name="PART_DecreaseButton"
                              Classes="repeattrack" />
@@ -46,7 +46,7 @@
             <ColumnDefinition Width="Auto"/>
           </Grid.ColumnDefinitions>
           <Border Name="TrackBackground" Grid.Column="1" Width="4" Margin="0,6" HorizontalAlignment="Center"/>
-          <Track Name="PART_Track" Grid.Column="1">
+          <Track Name="PART_Track" Grid.Column="1" Orientation="Vertical">
             <Track.DecreaseButton>
                <RepeatButton Name="PART_DecreaseButton"
                              Classes="repeattrack" />
@@ -72,8 +72,7 @@
   <Style Selector="Slider /template/ Track#PART_Track">
     <Setter Property="Minimum" Value="{TemplateBinding Minimum}"/>
     <Setter Property="Maximum" Value="{TemplateBinding Maximum}"/>
-    <Setter Property="Value" Value="{TemplateBinding Path=Value, Mode=TwoWay}"/>
-    <Setter Property="Orientation" Value="{TemplateBinding Orientation}"/>
+    <Setter Property="Value" Value="{TemplateBinding Value, Mode=TwoWay}"/>
   </Style>
   <Style Selector="Slider /template/ Border#TrackBackground">
     <Setter Property="BorderThickness" Value="2"/>

src/Avalonia.Themes.Default/TabControl.xaml

@@ -9,11 +9,11 @@
             <TabStrip Name="PART_TabStrip"
                       MemberSelector="{x:Static TabControl.HeaderSelector}"
                       Items="{TemplateBinding Items}"
-                      SelectedIndex="{TemplateBinding Path=SelectedIndex, Mode=TwoWay}"/>
+                      SelectedIndex="{TemplateBinding SelectedIndex, Mode=TwoWay}"/>
             <Carousel Name="PART_Content"
                       MemberSelector="{x:Static TabControl.ContentSelector}"
                       Items="{TemplateBinding Items}"
-                      SelectedIndex="{TemplateBinding Path=SelectedIndex}"
+                      SelectedIndex="{TemplateBinding SelectedIndex}"
                       PageTransition="{TemplateBinding PageTransition}"
                       Grid.Row="1"/>
           </DockPanel>

src/Avalonia.Themes.Default/TextBox.xaml

@@ -36,7 +36,7 @@
                   <TextBlock Name="watermark"
                              Opacity="0.5"
                              Text="{TemplateBinding Watermark}"
-                             IsVisible="{TemplateBinding Path=Text, Converter={x:Static StringConverters.NullOrEmpty}}"/>
+                             IsVisible="{TemplateBinding Text, Converter={x:Static StringConverters.NullOrEmpty}}"/>
                   <TextPresenter Name="PART_TextPresenter"
                                  Text="{TemplateBinding Text, Mode=TwoWay}"
                                  CaretIndex="{TemplateBinding CaretIndex}"

src/Avalonia.Themes.Default/TreeViewItem.xaml

@@ -7,14 +7,12 @@
           <Grid ColumnDefinitions="16, Auto">
             <ToggleButton Name="expander"
                           Focusable="False"
-                          IsChecked="{TemplateBinding Path=IsExpanded, Mode=TwoWay}"/>
+                          IsChecked="{TemplateBinding IsExpanded, Mode=TwoWay}"/>
             <ContentPresenter Name="PART_HeaderPresenter"
                               Background="{TemplateBinding Background}"
                               BorderBrush="{TemplateBinding BorderBrush}"
                               BorderThickness="{TemplateBinding BorderThickness}"
                               Content="{TemplateBinding Header}"
-                              HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
-                              VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                               Padding="{TemplateBinding Padding}"
                               TemplatedControl.IsTemplateFocusTarget="True"
                               Grid.Column="1"/>

src/Markup/Avalonia.Markup.Xaml/Avalonia.Markup.Xaml.csproj

@@ -48,7 +48,6 @@
         <Compile Include="Converters\SelectorTypeConverter.cs" />
         <Compile Include="MarkupExtensions\BindingExtension.cs" />
         <Compile Include="MarkupExtensions\RelativeSourceExtension.cs" />
-        <Compile Include="MarkupExtensions\TemplateBindingExtension.cs" />
         <Compile Include="PortableXaml\AvaloniaTypeAttributeProvider.cs" />
         <Compile Include="PortableXaml\AvaloniaXamlType.cs" />
         <Compile Include="PortableXaml\TypeDescriptorExtensions.cs" />

src/Markup/Avalonia.Markup.Xaml/AvaloniaXamlLoader.cs

@@ -139,7 +139,7 @@ public object Load(Uri uri, Uri baseUri = null, object rootInstance = null)
                     {
                         uriString = new Uri(baseUri, uri).AbsoluteUri;
                     }
-                    throw new XamlLoadException("Error loading xaml at " + uriString, e);
+                    throw new XamlLoadException("Error loading xaml at " + uriString + ": " + e.Message, e);
                 }
             }
         }

src/Markup/Avalonia.Markup.Xaml/Converters/AvaloniaPropertyTypeConverter.cs

@@ -2,85 +2,80 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
+using System.ComponentModel;
 using System.Globalization;
-using System.Linq;
+using System.Text.RegularExpressions;
+using Avalonia.Markup.Xaml.Templates;
+using Avalonia.Styling;
+using Portable.Xaml;
+using Portable.Xaml.ComponentModel;
+using Portable.Xaml.Markup;
 
 namespace Avalonia.Markup.Xaml.Converters
 {
-    using Avalonia.Styling;
-    using Portable.Xaml;
-    using Portable.Xaml.ComponentModel;
-    using System.ComponentModel;
-    using Portable.Xaml.Markup;
-
     public class AvaloniaPropertyTypeConverter : TypeConverter
     {
+        private static readonly Regex regex = new Regex(@"^\(?(\w*)\.(\w*)\)?|(.*)$");
+
         public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
         public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
         {
-            var s = (string)value;
+            var (owner, propertyName) = ParseProperty((string)value);
+            var ownerType = TryResolveOwnerByName(context, owner) ??
+                context.GetFirstAmbientValue<ControlTemplate>()?.TargetType ??
+                context.GetFirstAmbientValue<Style>()?.Selector?.TargetType;
 
-            string typeName;
-            string propertyName;
-            Type type = null;
+            if (ownerType == null)
+            {
+                throw new XamlLoadException(
+                    $"Could not determine the owner type for property '{propertyName}'. " +
+                    "Please fully qualify the property name or specify a target type on " +
+                    "the containing template.");
+            }
 
-            ParseProperty(s, out typeName, out propertyName);
+            var property = AvaloniaPropertyRegistry.Instance.FindRegistered(ownerType, propertyName);
 
-            if (typeName == null)
+            if (property == null)
             {
-                var style = context.GetFirstAmbientValue<Style>();
+                throw new XamlLoadException($"Could not find AvaloniaProperty '{ownerType.Name}.{propertyName}'.");
+            }
 
-                type = style?.Selector?.TargetType;
+            return property;
+        }
 
-                if (type == null)
-                {
-                    throw new Exception(
-                        "Could not determine the target type. Please fully qualify the property name.");
-                }
-            }
-            else
+        private Type TryResolveOwnerByName(ITypeDescriptorContext context, string owner)
+        {
+            if (owner != null)
             {
-                var typeResolver = context.GetService<IXamlTypeResolver>();
-                type = typeResolver.Resolve(typeName);
+                var resolver = context.GetService<IXamlTypeResolver>();
+                var result = resolver.Resolve(owner);
 
-                if (type == null)
+                if (result == null)
                 {
-                    throw new Exception($"Could not find type '{typeName}'.");
+                    throw new XamlLoadException($"Could not find type '{owner}'.");
                 }
-            }
-
-            AvaloniaProperty property = AvaloniaPropertyRegistry.Instance.FindRegistered(type, propertyName);
 
-            if (property == null)
-            {
-                throw new Exception(
-                    $"Could not find AvaloniaProperty '{type.Name}.{propertyName}'.");
+                return result;
             }
 
-            return property;
+            return null;
         }
 
-        private void ParseProperty(string s, out string typeName, out string propertyName)
+        private (string owner, string property) ParseProperty(string s)
         {
-            var split = s.Split('.');
+            var result = regex.Match(s);
 
-            if (split.Length == 1)
-            {
-                typeName = null;
-                propertyName = split[0];
-            }
-            else if (split.Length == 2)
+            if (result.Groups[1].Success)
             {
-                typeName = split[0];
-                propertyName = split[1];
+                return (result.Groups[1].Value, result.Groups[2].Value);
             }
             else
             {
-                throw new Exception($"Invalid property name: '{s}'.");
+                return (null, result.Groups[3].Value);
             }
         }
     }