[Core/Win] Add type icon support

Closes #118

Xamarin.PropertyEditing.Windows/PropertyEditorPanel.cs

@@ -3,10 +3,12 @@ using System.Collections;
 using System.Collections.ObjectModel;
 using System.Collections.Specialized;
 using System.ComponentModel;
+using System.IO;
 using System.Linq;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Data;
+using System.Windows.Media.Imaging;
 using Xamarin.PropertyEditing.ViewModels;
 
 namespace Xamarin.PropertyEditing.Windows
@@ -82,6 +84,7 @@ namespace Xamarin.PropertyEditing.Windows
 			base.OnApplyTemplate ();
 
 			this.root = (FrameworkElement) GetTemplateChild ("root");
+			this.typeIcon = (Image) GetTemplateChild ("typeIcon");
 			this.items = (ItemsControl) GetTemplateChild ("propertyItems");
 			this.propertiesPane = (FrameworkElement) GetTemplateChild ("propertiesPane");
 			this.eventsPane = (FrameworkElement) GetTemplateChild ("eventsPane");
@@ -99,6 +102,7 @@ namespace Xamarin.PropertyEditing.Windows
 		private ItemsControl items;
 		private ChoiceControl paneSelector;
 		private FrameworkElement propertiesPane, eventsPane;
+		private Image typeIcon;
 
 		private void OnPaneChanged (object sender, EventArgs e)
 		{
@@ -142,6 +146,28 @@ namespace Xamarin.PropertyEditing.Windows
 
 			if (ArrangeMode == PropertyArrangeMode.Name)
 				OnArrangeModeChanged (ArrangeMode);
+
+			UpdateIcon ();
+		}
+
+		private async void UpdateIcon ()
+		{
+			if (this.typeIcon == null)
+				return;
+
+			Stream icon = await this.vm.GetIconAsync ();
+			if (icon == null) {
+				this.typeIcon.Source = null;
+				this.typeIcon.Visibility = Visibility.Collapsed;
+			} else {
+				var source = new BitmapImage();
+				source.BeginInit();
+				source.StreamSource = icon;
+				source.EndInit();
+
+				this.typeIcon.Source = source;
+				this.typeIcon.Visibility = Visibility.Visible;
+			}
 		}
 
 		private void OnTargetPlatformChanged ()

Xamarin.PropertyEditing.Windows/Themes/PropertyEditorPanelStyle.xaml

@@ -112,8 +112,8 @@
 										<ColumnDefinition Width="Auto" />
 									</Grid.ColumnDefinitions>
 
-									<Border Visibility="Collapsed" Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Height="32" Width="32" Margin="1,6,5,2" Background="{DynamicResource PropertiesPanelIconBackgroundBrush}" VerticalAlignment="Center">
-										<!-- type icon -->
+									<Border Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Margin="1,6,5,2" Background="{DynamicResource PropertiesPanelIconBackgroundBrush}" VerticalAlignment="Center">
+										<Image Name="typeIcon" Height="32" Width="32" Visibility="Collapsed" />
 									</Border>
 
 									<TextBlock Visibility="{Binding IsObjectNameable, Converter={StaticResource BoolToVisibilityConverter}}" Name="nameLabel" Grid.Row="0" Grid.Column="1" Margin="0,2,0,2" Text="{x:Static prop:Resources.Name}" />

Xamarin.PropertyEditing/IIconProvider.cs

@@ -0,0 +1,18 @@
+using System.IO;
+using System.Threading.Tasks;
+
+namespace Xamarin.PropertyEditing
+{
+	public interface IIconProvider
+	{
+		/// <summary>
+		/// Gets an icon for the given <paramref name="types"/>.
+		/// </summary>
+		/// <param name="types">The types to get an icon for.</param>
+		/// <remarks>
+		/// The types provided in <paramref name="type"/> may not be the same.
+		/// If they aren't, you should return a generic icon (VS uses an XML Tag).
+		/// </remarks>
+		Task<Stream> GetTypeIconAsync (ITypeInfo[] types);
+	}
+}

Xamarin.PropertyEditing/TargetPlatform.cs

@@ -63,6 +63,12 @@ namespace Xamarin.PropertyEditing
 			private set;
 		}
 
+		public IIconProvider IconProvider
+		{
+			get;
+			set;
+		}
+
 		/// <summary>
 		/// Gets or sets whether the platform supports custom expressions (default false).
 		/// </summary>

Xamarin.PropertyEditing/ViewModels/PanelViewModel.cs

@@ -1,6 +1,8 @@
-using System;
+using System;
 using System.Collections.Generic;
-using System.Linq;
+ using System.IO;
+ using System.Linq;
+ using System.Threading.Tasks;
 
 namespace Xamarin.PropertyEditing.ViewModels
 {
@@ -88,6 +90,14 @@ namespace Xamarin.PropertyEditing.ViewModels
 			SetIsExpanded (ArrangeMode, group, isExpanded);
 		}
 
+		public Task<Stream> GetIconAsync ()
+		{
+			if (TargetPlatform.IconProvider == null)
+				return Task.FromResult<Stream> (null);
+
+			return TargetPlatform.IconProvider.GetTypeIconAsync (ObjectEditors.Select (oe => oe.TargetType).ToArray ());
+		}
+
 		protected override void OnAddEditors (IEnumerable<EditorViewModel> editors)
 		{
 			IEnumerable<EditorViewModel> props = Properties;

Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj

@@ -91,6 +91,7 @@
     <Compile Include="IProvidePath.cs" />
     <Compile Include="IResourceProvider.cs" />
     <Compile Include="ISelfConstrainedPropertyInfo.cs" />
+    <Compile Include="IIconProvider.cs" />
     <Compile Include="ITypeInfo.cs" />
     <Compile Include="IValidator.cs" />
     <Compile Include="KnownProperty.cs" />