mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/Base/Core/Internal/PropertyEditing/EditModeSwitchButtonKeyboardFix.cs

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4 namespace System.Activities.Presentation.Internal.PropertyEditing
   5 {
   6     using System;
   7     using System.Diagnostics;
   8     using System.Diagnostics.CodeAnalysis;
   9     using System.Globalization;
  10     using System.Windows;
  11     using System.Windows.Input;
  12     using System.Windows.Threading;
  13     using System.Activities.Presentation.PropertyEditing;
  14     using System.Runtime;
  15     using System.Activities.Presentation;
  16
  17     // <summary>
  18     // This is a fix for a bug in EditModeSwitchButton which lives in System.Activities.Presentation and
  19     // which has already been locked as an assembly.  EditModeSwitchButton only responds to MouseDown
  20     // events to make sure that the opening of the popup extended editor works correctly.  However,
  21     // that means that it will never respond to keyboard or automation events.  To fix it, this class
  22     // offers up an attached DP that, when used, hooks into events offered by EditModeSwitchButton
  23     // to correct this issue and still have the button do the right thing even if mouse is not involved
  24     // in invoking the button.
  25     //
  26     // This class is associated with every instance of EditModeSwitchButton using a setter in the
  27     // EditModeSwitchButton style:
  28     //
  29     //   &lt;Style TargetType="{x:Type PropertyEditing:EditModeSwitchButton}" BasedOn="{StaticResource {x:Type Button}}"&gt;
  30     //     ...
  31     //     &lt;Setter Property="Internal:EditModeSwitchButtonKeyboardFix.ApplyFix" Value="True" /&gt;
  32     // </summary>
  33
  34     class EditModeSwitchButtonKeyboardFix
  35     {
  36
  37         // <summary>
  38         // Property used to correct a problem with EditModeSwitchButton.  This property should only be
  39         // applied to EditModeSwitchButton class instances.
  40         // </summary>
  41         public static readonly DependencyProperty ApplyFixProperty = DependencyProperty.RegisterAttached(
  42             "ApplyFix",
  43             typeof(bool),
  44             typeof(EditModeSwitchButtonKeyboardFix),
  45             new PropertyMetadata(false, new PropertyChangedCallback(OnApplyFixPropertyChanged)));
  46
  47         private bool _clickInitiatedByMouse;
  48
  49         private EditModeSwitchButtonKeyboardFix(EditModeSwitchButton button)
  50         {
  51             button.Click += new RoutedEventHandler(OnEditModeSwitchButtonClick);
  52             button.PreviewMouseLeftButtonUp += new MouseButtonEventHandler(OnEditModeSwitchButtonPreviewMouseLeftButtonUp);
  53         }
  54
  55         // <summary>
  56         // Gets the value of ApplyFix property from the specified DependencyObject.
  57         // </summary>
  58         // <param name="obj"></param>
  59         // <returns></returns>
  60         public static bool GetApplyFix(DependencyObject obj)
  61         {
  62             if (obj == null)
  63             {
  64                 throw FxTrace.Exception.ArgumentNull("obj");
  65             }
  66
  67             return (bool)obj.GetValue(ApplyFixProperty);
  68         }
  69
  70         // <summary>
  71         // Sets the value of ApplyFix property onto the specified DependencyObject.  Only
  72         // instances of EditModeSwitchButton classes should be used as the targets of this property.
  73         // </summary>
  74         // <param name="obj"></param>
  75         // <param name="value"></param>
  76         public static void SetApplyFix(DependencyObject obj, bool value)
  77         {
  78             if (obj == null)
  79             {
  80                 throw FxTrace.Exception.ArgumentNull("obj");
  81             }
  82
  83             obj.SetValue(ApplyFixProperty, value);
  84         }
  85
  86         [SuppressMessage("Microsoft.Usage", "CA1806:DoNotIgnoreMethodResults")]
  87         private static void OnApplyFixPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e)
  88         {
  89             EditModeSwitchButton button = obj as EditModeSwitchButton;
  90             if (button == null)
  91             {
  92                 Debug.Fail("EditModeSwitchButtonKeyboardFix.ApplyFix fix can only be applied to EditModeSwitchButton instances.");
  93                 return;
  94             }
  95             if (object.Equals(e.NewValue, true))
  96             {
  97                 // Instantiating this class will make itself hook into EditModeSwitchButton's events,
  98                 // hence not be chewed up by garbage collector
  99                 new EditModeSwitchButtonKeyboardFix(button);
 100             }
 101         }
 102
 103         private void OnEditModeSwitchButtonPreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
 104         {
 105             _clickInitiatedByMouse = true;
 106
 107             ((DispatcherObject)sender).Dispatcher.BeginInvoke(DispatcherPriority.Input, new MethodInvoker(delegate()
 108             {
 109                 _clickInitiatedByMouse = false;
 110             }));
 111         }
 112
 113         private void OnEditModeSwitchButtonClick(object sender, RoutedEventArgs e)
 114         {
 115             if (_clickInitiatedByMouse)
 116             {
 117                 return;
 118             }
 119
 120             EditModeSwitchButton button = e.OriginalSource as EditModeSwitchButton;
 121             Fx.Assert(button != null, "Expected to see the EditModeSwitchButton at this point.");
 122             if (button == null)
 123             {
 124                 return;
 125             }
 126
 127             // At this point the click was initiated using the Invoke AutomationPeer pattern or
 128             // by using the keyboard.  So, make sure that the EditModeSwitchButton.OnMouseDown
 129             // button still executes.
 130             // Invoke the appropriate command
 131             switch (button.TargetEditMode)
 132             {
 133                 case PropertyContainerEditMode.Inline:
 134                     PropertyValueEditorCommands.ShowInlineEditor.Execute(null, button);
 135                     break;
 136                 case PropertyContainerEditMode.ExtendedPopup:
 137                     PropertyValueEditorCommands.ShowExtendedPopupEditor.Execute(null, button);
 138                     break;
 139                 case PropertyContainerEditMode.ExtendedPinned:
 140                     PropertyValueEditorCommands.ShowExtendedPinnedEditor.Execute(null, button);
 141                     break;
 142                 case PropertyContainerEditMode.Dialog:
 143                     PropertyValueEditorCommands.ShowDialogEditor.Execute(null, button);
 144                     break;
 145                 default:
 146                     Debug.Fail(string.Format(
 147                         CultureInfo.CurrentCulture,
 148                         "EditModeSwitchButtonKeyboardFix does not yet support PropertyContainerEditMode '{0}'.",
 149                         button.TargetEditMode.ToString()));
 150                     break;
 151             }
 152         }
 153         private delegate void MethodInvoker();
 154     }
 155 }