More work on Menu.

Perspex.Controls/IMenu.cs

@@ -0,0 +1,13 @@
+// -----------------------------------------------------------------------
+// <copyright file="IMenu.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls
+{
+    internal interface IMenu
+    {
+        void ChildPointerEnter(MenuItem item);
+    }
+}

Perspex.Controls/Menu.cs

@@ -4,11 +4,12 @@
 // </copyright>
 // -----------------------------------------------------------------------
 
-using Perspex.Controls.Generators;
-
 namespace Perspex.Controls
 {
-    public class Menu : ItemsControl
+    using System.Linq;
+    using Perspex.LogicalTree;
+
+    public class Menu : ItemsControl, IMenu
     {
         private static readonly ItemsPanelTemplate DefaultPanel =
             new ItemsPanelTemplate(() => new StackPanel { Orientation = Orientation.Horizontal });
@@ -17,5 +18,18 @@ namespace Perspex.Controls
         {
             ItemsPanelProperty.OverrideDefaultValue(typeof(Menu), DefaultPanel);
         }
+
+        void IMenu.ChildPointerEnter(MenuItem item)
+        {
+            var children = this.GetLogicalChildren().Cast<MenuItem>();
+
+            if (children.Any(x => x.IsSubMenuOpen))
+            {
+                foreach (MenuItem i in this.GetLogicalChildren())
+                {
+                    i.IsSubMenuOpen = i == item;
+                }
+            }
+        }
     }
 }

Perspex.Controls/MenuItem.cs

@@ -8,15 +8,35 @@ namespace Perspex.Controls
 {
     using Perspex.Controls.Primitives;
     using Perspex.Input;
+    using Perspex.LogicalTree;
+    using System.Windows.Input;
 
     public class MenuItem : HeaderedItemsControl
     {
+        public static readonly PerspexProperty<ICommand> CommandProperty =
+            Button.CommandProperty.AddOwner<MenuItem>();
+
+        public static readonly PerspexProperty<object> CommandParameterProperty =
+            Button.CommandParameterProperty.AddOwner<MenuItem>();
+
         public static readonly PerspexProperty<object> IconProperty =
             PerspexProperty.Register<MenuItem, object>("Icon");
 
         public static readonly PerspexProperty<bool> IsSubMenuOpenProperty =
             PerspexProperty.Register<MenuItem, bool>("IsSubMenuOpen");
 
+        public ICommand Command
+        {
+            get { return this.GetValue(CommandProperty); }
+            set { this.SetValue(CommandProperty, value); }
+        }
+
+        public object CommandParameter
+        {
+            get { return this.GetValue(CommandParameterProperty); }
+            set { this.SetValue(CommandParameterProperty, value); }
+        }
+
         public object Icon
         {
             get { return this.GetValue(IconProperty); }
@@ -29,10 +49,20 @@ namespace Perspex.Controls
             set { this.SetValue(IsSubMenuOpenProperty, value); }
         }
 
+        protected override void OnPointerEnter(PointerEventArgs e)
+        {
+            base.OnPointerEnter(e);
+            this.GetLogicalParent<IMenu>()?.ChildPointerEnter(this);
+        }
+
         protected override void OnPointerPressed(PointerPressEventArgs e)
         {
             base.OnPointerPressed(e);
-            this.IsSubMenuOpen = !this.IsSubMenuOpen;
+
+            if (!this.Classes.Contains(":empty"))
+            {
+                this.IsSubMenuOpen = !this.IsSubMenuOpen;
+            }
         }
     }
 }

Perspex.Controls/Perspex.Controls.csproj

@@ -37,6 +37,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Border.cs" />
+    <Compile Include="IMenu.cs" />
     <Compile Include="MenuItem.cs" />
     <Compile Include="Menu.cs" />
     <Compile Include="Button.cs" />

Perspex.Themes.Default/MenuItemStyle.cs

@@ -45,6 +45,21 @@ namespace Perspex.Themes.Default
                         new Setter(Border.BorderBrushProperty, new SolidColorBrush(0xff26a0da)),
                     },
                 },
+                new Style(x => x.OfType<MenuItem>().Class(":empty").Template().Name("rightArrow"))
+                {
+                    Setters = new[]
+                    {
+                        new Setter(Path.IsVisibleProperty, false),
+                    },
+                },
+                new Style(x => x.OfType<MenuItem>().PropertyEquals(MenuItem.IsSubMenuOpenProperty, true).Template().Name("root"))
+                {
+                    Setters = new[]
+                    {
+                        new Setter(Border.BackgroundProperty, new SolidColorBrush(0x3d26a0da)),
+                        new Setter(Border.BorderBrushProperty, new SolidColorBrush(0xff26a0da)),
+                    },
+                },
             });
         }
 
@@ -71,7 +86,7 @@ namespace Perspex.Themes.Default
                         (popup = new Popup
                         {
                             Name = "popup",
-                            StaysOpen = false,
+                            StaysOpen = true,
                             [!!Popup.IsOpenProperty] = control[!!MenuItem.IsSubMenuOpenProperty],
                             Child = new Border
                             {
@@ -160,10 +175,20 @@ namespace Perspex.Themes.Default
                             [~ContentPresenter.MarginProperty] = control[~MenuItem.PaddingProperty],
                             [Grid.ColumnProperty] = 2,
                         },
+                        new Path
+                        {
+                            Name = "rightArrow",
+                            Data = StreamGeometry.Parse("M0,0L4,3.5 0,7z"),
+                            Fill = new SolidColorBrush(0xff212121),
+                            Margin = new Thickness(10, 0, 0, 0),
+                            UseLayoutRounding = false,
+                            VerticalAlignment = VerticalAlignment.Center,
+                            [Grid.ColumnProperty] = 3,
+                        },
                         (popup = new Popup
                         {
                             Name = "popup",
-                            StaysOpen = false,
+                            StaysOpen = true,
                             [!!Popup.IsOpenProperty] = control[!!MenuItem.IsSubMenuOpenProperty],
                             Child = new Border
                             {

TestApplication/Program.cs

@@ -151,6 +151,17 @@ namespace TestApplication
                                         new MenuItem
                                         {
                                             Header = "Save",
+                                            Items = new[]
+                                            {
+                                                new MenuItem
+                                                {
+                                                    Header = "Sub Item 1",
+                                                },
+                                                new MenuItem
+                                                {
+                                                    Header = "Sub Item 2",
+                                                },
+                                            }
                                         },
                                         new MenuItem
                                         {