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//---------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
// File: Menu.cs
//
//---------------------------------------------------------------------------
using MS.Internal;
using MS.Internal.KnownBoxes;
using MS.Utility;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows.Threading;
#if OLD_AUTOMATION
using System.Windows.Automation.Provider;
#endif
using System.Windows.Media;
using System.Windows.Input;
using System.Windows.Controls.Primitives;
using System;
using System.Security;
using System.Security.Permissions;
using MS.Internal.Telemetry.PresentationFramework;
namespace System.Windows.Controls
{
/// <summary>
/// Control that defines a menu of choices for users to invoke.
/// </summary>
#if OLD_AUTOMATION
[Automation(AccessibilityControlType = "Menu")]
#endif
public class Menu : MenuBase
{
//-------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------
#region Constructors
/// <summary>
/// Default DependencyObject constructor
/// </summary>
/// <remarks>
/// Automatic determination of current Dispatcher. Use alternative constructor
/// that accepts a Dispatcher for best performance.
/// </remarks>
public Menu() : base()
{
}
static Menu()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(Menu), new FrameworkPropertyMetadata(typeof(Menu)));
_dType = DependencyObjectType.FromSystemTypeInternal(typeof(Menu));
ItemsPanelProperty.OverrideMetadata(typeof(Menu), new FrameworkPropertyMetadata(GetDefaultPanel()));
IsTabStopProperty.OverrideMetadata(typeof(Menu), new FrameworkPropertyMetadata(false));
KeyboardNavigation.ControlTabNavigationProperty.OverrideMetadata(typeof(Menu), new FrameworkPropertyMetadata(KeyboardNavigationMode.Once));
KeyboardNavigation.DirectionalNavigationProperty.OverrideMetadata(typeof(Menu), new FrameworkPropertyMetadata(KeyboardNavigationMode.Cycle));
EventManager.RegisterClassHandler(typeof(Menu), AccessKeyManager.AccessKeyPressedEvent, new AccessKeyPressedEventHandler(OnAccessKeyPressed));
ControlsTraceLogger.AddControl(TelemetryControls.Menu);
}
private static ItemsPanelTemplate GetDefaultPanel()
{
FrameworkElementFactory panel = new FrameworkElementFactory(typeof(WrapPanel));
ItemsPanelTemplate template = new ItemsPanelTemplate(panel);
template.Seal();
return template;
}
#endregion
//-------------------------------------------------------------------
//
// Public Methods
//
//-------------------------------------------------------------------
/// <summary>
/// DependencyProperty for the IsMainMenuProperty
/// </summary>
public static readonly DependencyProperty IsMainMenuProperty =
DependencyProperty.Register(
"IsMainMenu",
typeof(bool),
typeof(Menu),
new FrameworkPropertyMetadata(
BooleanBoxes.TrueBox,
new PropertyChangedCallback(OnIsMainMenuChanged)));
/// <summary>
/// True if this menu will participate in main menu activation notification.
/// If there are multiple menus on a page, menus that do not wish to receive ALT or F10
/// key notification should set this property to false.
/// </summary>
/// <value></value>
public bool IsMainMenu
{
get { return (bool) GetValue(IsMainMenuProperty); }
set { SetValue(IsMainMenuProperty, BooleanBoxes.Box(value)); }
}
private static void OnIsMainMenuChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
Menu menu = d as Menu;
if ((bool) e.NewValue)
{
menu.SetupMainMenu();
}
else
{
menu.CleanupMainMenu();
}
}
/// <summary>
/// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
/// </summary>
protected override System.Windows.Automation.Peers.AutomationPeer OnCreateAutomationPeer()
{
return new System.Windows.Automation.Peers.MenuAutomationPeer(this);
}
/// <summary>
/// This virtual method in called when IsInitialized is set to true and it raises an Initialized event
/// </summary>
protected override void OnInitialized(EventArgs e)
{
base.OnInitialized(e);
if (IsMainMenu)
{
SetupMainMenu();
}
}
/// <SecurityNote>
/// Critical: This sets up a handler for entering menu mode which will recieve a presentationsource
/// TreatAsSafe: The function that it hooks is safe to expose since it does not expose the source
/// </SecurityNote>
[SecurityCritical,SecurityTreatAsSafe]
private void SetupMainMenu()
{
if (_enterMenuModeHandler == null)
{
_enterMenuModeHandler = new KeyboardNavigation.EnterMenuModeEventHandler(OnEnterMenuMode);
(new UIPermission(UIPermissionWindow.AllWindows)).Assert(); //Blessed Assert
try
{
KeyboardNavigation.Current.EnterMenuMode += _enterMenuModeHandler;
}
finally
{
UIPermission.RevertAssert();
}
}
}
private void CleanupMainMenu()
{
if (_enterMenuModeHandler != null)
{
KeyboardNavigation.Current.EnterMenuMode -= _enterMenuModeHandler;
}
}
private static object OnGetIsMainMenu(DependencyObject d)
{
return BooleanBoxes.Box(((Menu)d).IsMainMenu);
}
//-------------------------------------------------------------------
//
// Protected Methods
//
//-------------------------------------------------------------------
#region Protected Methods
/// <summary>
/// Prepare the element to display the item. This may involve
/// applying styles, setting bindings, etc.
/// </summary>
protected override void PrepareContainerForItemOverride(DependencyObject element, object item)
{
base.PrepareContainerForItemOverride(element, item);
MenuItem.PrepareMenuItem(element, item);
}
/// <summary>
/// This is the method that responds to the KeyDown event.
/// </summary>
/// <param name="e">Event arguments</param>
protected override void OnKeyDown(KeyEventArgs e)
{
base.OnKeyDown(e);
if (e.Handled) return;
Key key = e.Key;
switch (key)
{
case Key.Down:
case Key.Up:
if (CurrentSelection != null)
{
// Only for non vertical layout Up/Down open the submenu
Panel itemsHost = ItemsHost;
bool isVertical = itemsHost != null && itemsHost.HasLogicalOrientation && itemsHost.LogicalOrientation == Orientation.Vertical;
if (!isVertical)
{
CurrentSelection.OpenSubmenuWithKeyboard();
e.Handled = true;
}
}
break;
case Key.Left:
case Key.Right:
if (CurrentSelection != null)
{
// Only for vertical layout Left/Right open the submenu
Panel itemsHost = ItemsHost;
bool isVertical = itemsHost != null && itemsHost.HasLogicalOrientation && itemsHost.LogicalOrientation == Orientation.Vertical;
if (isVertical)
{
CurrentSelection.OpenSubmenuWithKeyboard();
e.Handled = true;
}
}
break;
}
}
/// <summary>
/// This is the method that responds to the TextInput event.
/// </summary>
/// <param name="e">Event arguments</param>
/// <SecurityNote>
/// Critical: accesses ShowSystemMenu & CriticalFromVisual
/// TreatAsSafe: limited to only UserInitiated input.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
protected override void OnTextInput(TextCompositionEventArgs e)
{
base.OnTextInput(e);
if (e.Handled) return;
// We don't use win32 menu's, so we need to emulate the win32
// behavior for hitting Space while in menu mode. Alt+Space
// will be handled as a SysKey by the DefaultWindowProc, but
// Alt, then Space needs to be special cased here because we prevent win32.
// from entering menu mode. In WPF the equiv. of win32 menu mode is having
// a main menu with focus and no menu items opened.
if (e.UserInitiated &&
e.Text == " " &&
IsMainMenu &&
(CurrentSelection == null || !CurrentSelection.IsSubmenuOpen))
{
// We need to exit menu mode because it holds capture and prevents
// the system menu from showing.
IsMenuMode = false;
System.Windows.Interop.HwndSource source = PresentationSource.CriticalFromVisual(this) as System.Windows.Interop.HwndSource;
if (source != null)
{
source.ShowSystemMenu();
e.Handled = true;
}
}
}
/// <summary>
/// Called when any mouse button is pressed or released on this subtree
/// </summary>
/// <param name="e">Event arguments.</param>
protected override void HandleMouseButton(MouseButtonEventArgs e)
{
base.HandleMouseButton(e);
if (e.Handled)
{
return;
}
if (e.ChangedButton != MouseButton.Left && e.ChangedButton != MouseButton.Right)
{
return;
}
// We want to dismiss when someone clicks on the menu bar, so
// really we're interested in clicks that bubble up from an
// element whose TemplatedParent is the Menu.
if (IsMenuMode)
{
FrameworkElement element = e.OriginalSource as FrameworkElement;
if ((element != null && (element == this || element.TemplatedParent == this)))
{
IsMenuMode = false;
e.Handled = true;
}
}
}
internal override bool FocusItem(ItemInfo info, ItemNavigateArgs itemNavigateArgs)
{
bool returnValue = base.FocusItem(info, itemNavigateArgs);
// Trying to navigate from the current menuitem (this) to an adjacent menuitem.
if (itemNavigateArgs.DeviceUsed is KeyboardDevice)
{
// If the item is a TopLevelHeader then when you navigate onto it, the submenu will open
// and we should select the first item in the submenu. The parent MenuItem will take care
// of opening the submenu but doesn't know whether focus changed because of a mouse action
// or a keyboard action. Help out by focusing the first thing in the new submenu.
// Assume that KeyboardNavigation.Current.Navigate moved focus onto the element onto which
// it navigated.
MenuItem newSelection = info.Container as MenuItem;
if (newSelection != null
&& newSelection.Role == MenuItemRole.TopLevelHeader
&& newSelection.IsSubmenuOpen)
{
newSelection.NavigateToStart(itemNavigateArgs);
}
}
return returnValue;
}
#endregion
//-------------------------------------------------------------------
//
// Private Methods
//
//-------------------------------------------------------------------
#region Private Methods
private static void OnAccessKeyPressed(object sender, AccessKeyPressedEventArgs e)
{
// If ALT is down, then blend our scope into the one above. Maybe bad, but only if Menu is not top-level.
if (!(Keyboard.IsKeyDown(Key.LeftAlt) || Keyboard.IsKeyDown(Key.RightAlt)))
{
e.Scope = sender;
e.Handled = true;
}
}
/// <SecurityNote>
/// Critical - as this calls PresentationSource.CriticalFromVisual() .
/// Safe - as this doesn't return PresentationSource thus obtained.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private bool OnEnterMenuMode(object sender, EventArgs e)
{
// Don't enter menu mode if someone has capture
if (Mouse.Captured != null)
return false;
// Need to check that ALT/F10 happened in our source.
PresentationSource source = sender as PresentationSource;
PresentationSource mySource = null;
mySource = PresentationSource.CriticalFromVisual(this);
if (source == mySource)
{
// Give focus to the first possible element in the ItemsControl
for (int i = 0; i < Items.Count; i++)
{
MenuItem menuItem = ItemContainerGenerator.ContainerFromIndex(i) as MenuItem;
if (menuItem != null && !(Items[i] is Separator))
{
if (menuItem.Focus())
{
return true;
}
}
}
}
return false;
}
//
// This property
// 1. Finds the correct initial size for the _effectiveValues store on the current DependencyObject
// 2. This is a performance optimization
//
internal override int EffectiveValuesInitialSize
{
get { return 28; }
}
#endregion
//-------------------------------------------------------------------
//
// Private Fields
//
//-------------------------------------------------------------------
#region Private Fields
private KeyboardNavigation.EnterMenuModeEventHandler _enterMenuModeHandler;
#endregion
#region DTypeThemeStyleKey
// Returns the DependencyObjectType for the registered ThemeStyleKey's default
// value. Controls will override this method to return approriate types.
internal override DependencyObjectType DTypeThemeStyleKey
{
get { return _dType; }
}
private static DependencyObjectType _dType;
#endregion DTypeThemeStyleKey
}
}
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