More work on Menu.

Perspex.Controls/Menu.cs

@@ -72,7 +72,7 @@ namespace Perspex.Controls
         /// <summary>
         /// Closes the menu.
         /// </summary>
-        public void CloseMenu()
+        public void Close()
         {
             foreach (MenuItem i in this.GetLogicalChildren())
             {
@@ -86,10 +86,11 @@ namespace Perspex.Controls
         /// <summary>
         /// Opens the menu in response to the Alt/F10 key.
         /// </summary>
-        public void OpenMenu()
+        public void Open()
         {
             this.SelectedIndex = 0;
-            ((IInputElement)this.SelectedItem)?.Focus();
+            this.SelectedMenuItem.Focus();
+            this.IsOpen = true;
         }
 
         /// <summary>
@@ -138,7 +139,7 @@ namespace Perspex.Controls
         protected override void OnLostFocus(RoutedEventArgs e)
         {
             base.OnLostFocus(e);
-            //this.CloseMenu();
+            //this.Close();
         }
 
         /// <summary>
@@ -151,12 +152,7 @@ namespace Perspex.Controls
 
             base.OnKeyDown(e);
 
-            if (this.IsOpen && e.Key == Key.Escape)
-            {
-                this.CloseMenu();
-                e.Handled = true;
-            }
-            else if (menuWasOpen)
+            if (menuWasOpen)
             {
                 // If a menu item was open and we navigate to a new one with the arrow keys, open
                 // that menu and select the first item.
@@ -199,7 +195,7 @@ namespace Perspex.Controls
         /// <param name="e">The event args.</param>
         private void Deactivated(object sender, EventArgs e)
         {
-            this.CloseMenu();
+            this.Close();
         }
 
         /// <summary>
@@ -208,7 +204,7 @@ namespace Perspex.Controls
         /// <param name="e">The event args.</param>
         private void OnMenuClick(RoutedEventArgs e)
         {
-            this.CloseMenu();
+            this.Close();
         }
 
         /// <summary>
@@ -224,7 +220,7 @@ namespace Perspex.Controls
 
                 if (!this.IsLogicalParentOf(control))
                 {
-                    this.CloseMenu();
+                    this.Close();
                 }
             }
         }

Perspex.Controls/MenuItem.cs

@@ -277,10 +277,6 @@ namespace Perspex.Controls
                     }
 
                     break;
-
-                default:
-                    e.Handled = this.HandleAccessKey(e.Text);
-                    break;
             }
 
             if (!passStraightToParent)
@@ -289,60 +285,6 @@ namespace Perspex.Controls
             }
         }
 
-        private bool HandleAccessKey(string text)
-        {
-            text = text.ToUpper();
-
-            if (!this.IsSubMenuOpen)
-            {
-                var match = this.GetVisualDescendents()
-                    .OfType<AccessText>()
-                    .FirstOrDefault(x => x.AccessKey.ToString().ToUpper() == text);
-
-                if (match != null)
-                {
-                    if (this.HasSubMenu)
-                    {
-                        this.IsSubMenuOpen = true;
-                    }
-                    else
-                    {
-                        this.RaiseEvent(new RoutedEventArgs(ClickEvent));
-                    }
-
-                    return true;
-                }
-            }
-            else
-            {
-                var match = this.popup.PopupRoot.GetVisualDescendents()
-                    .OfType<AccessText>()
-                    .FirstOrDefault(x => x.AccessKey.ToString().ToUpper() == text)
-                    ?.GetVisualAncestors()
-                    .OfType<MenuItem>()
-                    .FirstOrDefault();
-
-                if (match != null)
-                {
-                    var item = (MenuItem)this.ItemContainerGenerator.GetItemForContainer(match);
-
-                    if (item.HasSubMenu)
-                    {
-                        item.SelectedIndex = 0;
-                        item.IsSubMenuOpen = true;
-                    }
-                    else
-                    {
-                        item.RaiseEvent(new RoutedEventArgs(ClickEvent));
-                    }
-
-                    return true;
-                }
-            }
-
-            return false;
-        }
-
         /// <summary>
         /// Called when the pointer enters the <see cref="MenuItem"/>.
         /// </summary>

Perspex.Controls/MenuItemAccessKeyHandler.cs

@@ -92,14 +92,19 @@ namespace Perspex.Controls
         /// <param name="e">The event args.</param>
         protected virtual void OnKeyDown(object sender, KeyEventArgs e)
         {
-            var text = e.Text.ToUpper();
-            var focus = this.registered
-                .Where(x => x.Item1 == text && x.Item2.IsEffectivelyVisible)
-                .FirstOrDefault()?.Item2;
-
-            if (focus != null)
+            if (!string.IsNullOrWhiteSpace(e.Text))
             {
-                focus.RaiseEvent(new RoutedEventArgs(AccessKeyHandler.AccessKeyPressedEvent));
+                var text = e.Text.ToUpper();
+                var focus = this.registered
+                    .Where(x => x.Item1 == text && x.Item2.IsEffectivelyVisible)
+                    .FirstOrDefault()?.Item2;
+
+                if (focus != null)
+                {
+                    focus.RaiseEvent(new RoutedEventArgs(AccessKeyHandler.AccessKeyPressedEvent));
+                }
+
+                e.Handled = true;
             }
         }
     }

Perspex.Input/AccessKeyHandler.cs

@@ -10,6 +10,7 @@ namespace Perspex.Input
     using System.Collections.Generic;
     using System.Linq;
     using Perspex.Interactivity;
+    using Perspex.VisualTree;
 
     /// <summary>
     /// Handles access keys for a window.
@@ -40,6 +41,11 @@ namespace Perspex.Input
         /// </summary>
         private bool showingAccessKeys;
 
+        /// <summary>
+        /// Whether to ignore the Alt KeyUp event.
+        /// </summary>
+        private bool ignoreAltUp;
+
         /// <summary>
         /// Gets or sets the window's main menu.
         /// </summary>
@@ -64,6 +70,7 @@ namespace Perspex.Input
             this.owner = owner;
 
             this.owner.AddHandler(InputElement.KeyDownEvent, this.OnPreviewKeyDown, RoutingStrategies.Tunnel);
+            this.owner.AddHandler(InputElement.KeyDownEvent, this.OnKeyDown, RoutingStrategies.Bubble);
             this.owner.AddHandler(InputElement.KeyUpEvent, this.OnPreviewKeyUp, RoutingStrategies.Tunnel);
             this.owner.AddHandler(InputElement.PointerPressedEvent, this.OnPreviewPointerPressed, RoutingStrategies.Tunnel);
         }
@@ -98,7 +105,7 @@ namespace Perspex.Input
         }
 
         /// <summary>
-        /// Handles the Alt key being pressed in the window.
+        /// Called when a key is pressed in the owner window.
         /// </summary>
         /// <param name="sender">The event sender.</param>
         /// <param name="e">The event args.</param>
@@ -106,19 +113,61 @@ namespace Perspex.Input
         {
             if (e.Key == Key.LeftAlt)
             {
-                this.owner.ShowAccessKeys = this.showingAccessKeys = true;
+                if (this.MainMenu == null || !this.MainMenu.IsOpen)
+                {
+                    // When Alt is pressed without a main menu, or with a closed main menu, show
+                    // access key markers in the window (i.e. "_File").
+                    this.owner.ShowAccessKeys = this.showingAccessKeys = true;
+                }
+                else
+                {
+                    // If the Alt key is pressed and the main menu is open, close the main menu.
+                    this.CloseMenu();
+                    this.ignoreAltUp = true;
+                }
+
+                // We always handle the Alt key.
+                e.Handled = true;
+            }
+        }
+
+        /// <summary>
+        /// Called when a key is pressed in the owner window.
+        /// </summary>
+        /// <param name="sender">The event sender.</param>
+        /// <param name="e">The event args.</param>
+        protected virtual void OnKeyDown(object sender, KeyEventArgs e)
+        {
+            bool menuIsOpen = this.MainMenu?.IsOpen == true;
+
+            if (e.Key == Key.Escape && menuIsOpen)
+            {
+                // When the Escape key is pressed with the main menu open, close it.
+                this.CloseMenu();
                 e.Handled = true;
             }
-            else if ((KeyboardDevice.Instance.Modifiers & ModifierKeys.Alt) != 0)
+            else if ((KeyboardDevice.Instance.Modifiers & ModifierKeys.Alt) != 0 || menuIsOpen)
             {
+                // If any other key is pressed with the Alt key held down, or the main menu is open,
+                // find all controls who have registered that access key.
                 var text = e.Text.ToUpper();
-                var focus = this.registered
+                var matches = this.registered
                     .Where(x => x.Item1 == text && x.Item2.IsEffectivelyVisible)
-                    .FirstOrDefault()?.Item2;
+                    .Select(x => x.Item2);
+
+                // If the menu is open, only match controls in the menu's visual tree.
+                if (menuIsOpen)
+                {
+                    matches = matches.Where(x => this.MainMenu.IsVisualParentOf(x));
+                }
+
+                var match = matches.FirstOrDefault();
 
-                if (focus != null)
+                // If there was a match, raise the AccessKeyPressed event on it.
+                if (match != null)
                 {
-                    focus.RaiseEvent(new RoutedEventArgs(AccessKeyPressedEvent));
+                    match.RaiseEvent(new RoutedEventArgs(AccessKeyPressedEvent));
+                    e.Handled = true;
                 }
             }
         }
@@ -133,9 +182,13 @@ namespace Perspex.Input
             switch (e.Key)
             {
                 case Key.LeftAlt:
-                    if (this.showingAccessKeys && this.MainMenu != null)
+                    if (this.ignoreAltUp)
+                    {
+                        this.ignoreAltUp = false;
+                    }
+                    else if (this.showingAccessKeys && this.MainMenu != null)
                     {
-                        this.MainMenu.OpenMenu();
+                        this.MainMenu.Open();
                         e.Handled = true;
                     }
 
@@ -143,7 +196,7 @@ namespace Perspex.Input
 
                 case Key.F10:
                     this.owner.ShowAccessKeys = this.showingAccessKeys = true;
-                    this.MainMenu.OpenMenu();
+                    this.MainMenu.Open();
                     e.Handled = true;
                     break;
             }
@@ -161,5 +214,14 @@ namespace Perspex.Input
                 this.owner.ShowAccessKeys = false;
             }
         }
+
+        /// <summary>
+        /// Closes the <see cref="MainMenu"/> and performs other bookeeping.
+        /// </summary>
+        private void CloseMenu()
+        {
+            this.MainMenu.Close();
+            this.owner.ShowAccessKeys = this.showingAccessKeys = false;
+        }
     }
 }

Perspex.Input/IMainMenu.cs

@@ -9,11 +9,21 @@ namespace Perspex.Input
     /// <summary>
     /// Defines the interface for a window's main menu.
     /// </summary>
-    public interface IMainMenu
+    public interface IMainMenu : IVisual
     {
+        /// <summary>
+        /// Gets a value indicating whether the menu is open.
+        /// </summary>
+        bool IsOpen { get; }
+
+        /// <summary>
+        /// Closes the menu.
+        /// </summary>
+        void Close();
+
         /// <summary>
         /// Opens the menu in response to the Alt/F10 key.
         /// </summary>
-        void OpenMenu();
+        void Open();
     }
 }

Perspex.SceneGraph/VisualTree/VisualExtensions.cs

@@ -117,5 +117,10 @@ namespace Perspex.VisualTree
 
             return visual;
         }
+
+        public static bool IsVisualParentOf(this IVisual visual, IVisual target)
+        {
+            return target.GetVisualAncestors().Any(x => x == visual);
+        }
     }
 }