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

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4 namespace System.Activities.Presentation.Internal.PropertyEditing.Automation
   5 {
   6     using System;
   7     using System.Collections;
   8     using System.Collections.Generic;
   9     using System.ComponentModel;
  10     using System.Text;
  11     using System.Windows;
  12     using System.Windows.Automation;
  13     using System.Windows.Automation.Peers;
  14     using System.Windows.Automation.Provider;
  15     using System.Windows.Controls;
  16     using System.Windows.Media;
  17
  18     using System.Activities.Presentation;
  19     using System.Activities.Presentation.PropertyEditing;
  20
  21     using System.Activities.Presentation.Internal.PropertyEditing.FromExpression.Framework.PropertyInspector;
  22     using System.Activities.Presentation.Internal.PropertyEditing.Selection;
  23
  24     // <summary>
  25     // AutomationPeer for PropertyContainer
  26     // </summary>
  27     internal class PropertyContainerAutomationPeer : UIElementAutomationPeer, IValueProvider, IScrollItemProvider, IAutomationFocusChangedEventSource
  28     {
  29
  30         private PropertyContainer _container;
  31
  32         // <summary>
  33         // Basic ctor
  34         // </summary>
  35         // <param name="container"></param>
  36         public PropertyContainerAutomationPeer(PropertyContainer container)
  37             : base(container)
  38         {
  39             if (container == null)
  40             {
  41                 throw FxTrace.Exception.ArgumentNull("container");
  42             }
  43
  44             _container = container;
  45         }
  46
  47         // <summary>
  48         // Gets a value indicating whether the contained PropertyContainer is read-only
  49         // </summary>
  50         public bool IsReadOnly
  51         {
  52             get { return _container.PropertyEntry.IsReadOnly || !_container.PropertyEntry.PropertyValue.CanConvertFromString; }
  53         }
  54
  55         // <summary>
  56         // Gets the value of the property within the PropertyContainer
  57         // </summary>
  58         public string Value
  59         {
  60             get { return _container.PropertyEntry.PropertyValue.StringValue; }
  61         }
  62
  63
  64         // IScrollItemProvider Members
  65
  66         // <summary>
  67         //  This public method is called when parent creates the CategoryContainerItemAutomationPeer
  68         //  in the GetChildrenCore, thus listening to the changes in the IsSelectedProperty.
  69         // </summary>
  70         internal void AddFocusEvents()
  71         {
  72             if (_container != null)
  73             {
  74                 HookUpFocusEvents(_container, OnIsSelectedValueChanged);
  75             }
  76         }
  77
  78         // <summary>
  79         // "PropertyContainer"
  80         // </summary>
  81         // <returns>"PropertyContainer"</returns>
  82         protected override string GetClassNameCore()
  83         {
  84             return typeof(PropertyContainer).Name;
  85         }
  86
  87         // <summary>
  88         // Returns the name of the contained property
  89         // </summary>
  90         // <returns></returns>
  91         protected override string GetNameCore()
  92         {
  93             return _container.PropertyEntry == null ? string.Empty : _container.PropertyEntry.DisplayName;
  94         }
  95
  96         // <summary>
  97         // Currently supported patterns: Value
  98         // </summary>
  99         // <param name="patternInterface"></param>
 100         // <returns></returns>
 101         public override object GetPattern(PatternInterface patternInterface)
 102         {
 103             if (patternInterface == PatternInterface.Value)
 104             {
 105                 return this;
 106             }
 107             else if (patternInterface == PatternInterface.ScrollItem)
 108             {
 109                 return this;
 110             }
 111
 112             return base.GetPattern(patternInterface);
 113         }
 114
 115         // <summary>
 116         // Private helper function to listen to the changes in the IsSelectedProperty,
 117         // which then fires the OnValueChanged event.
 118         // </summary>
 119         // <param name="expander">Expander control</param>
 120         // <param name="valueChangedEvent">ValueChanged event</param>
 121         private static void HookUpFocusEvents(PropertyContainer container, EventHandler valueChangedEvent)
 122         {
 123             if (container != null)
 124             {
 125                 DependencyPropertyDescriptor dpd = DependencyPropertyDescriptor.FromProperty(PropertySelection.IsSelectedProperty, typeof(PropertyContainer));
 126                 if (dpd != null)
 127                 {
 128                     dpd.AddValueChanged(container, valueChangedEvent);
 129                 }
 130             }
 131         }
 132
 133         // <summary>
 134         // The actual event handler, that fires when the IsSelected DP changes.
 135         // Here we raise the AutomationFocus event for the
 136         // Advanced (More Properties) properties expander.
 137         // </summary>
 138         // <param name="sender">Expander</param>
 139         // <param name="e">EventArgs</param>
 140         private void OnIsSelectedValueChanged(object sender, EventArgs e)
 141         {
 142             // Add logic to respond to "Selection"
 143             bool curVal = PropertySelection.GetIsSelected(sender as DependencyObject);
 144             if (curVal)
 145             {
 146                 this.RaiseAutomationEvent(AutomationEvents.AutomationFocusChanged);
 147             }
 148         }
 149
 150         // <summary>
 151         //  This public method is called when parent creates the CategoryContainerItemAutomationPeer
 152         //  in the GetChildrenCore, thus clearing off all the event listeners before we add new ones
 153         // </summary>
 154         public void RemoveFocusEvents()
 155         {
 156             if (_container != null)
 157             {
 158                 UnHookFocusEvents(_container, OnIsSelectedValueChanged);
 159             }
 160         }
 161
 162         // <summary>
 163         // Private method to unhook the ValueChanged event.
 164         // </summary>
 165         // <param name="expander">Expander</param>
 166         // <param name="valueChangedEvent">ValueChanged event</param>
 167         private static void UnHookFocusEvents(PropertyContainer container, EventHandler valueChangedEvent)
 168         {
 169             if (container != null)
 170             {
 171                 DependencyPropertyDescriptor dpd = DependencyPropertyDescriptor.FromProperty(PropertySelection.IsSelectedProperty, typeof(PropertyContainer));
 172                 if (dpd != null)
 173                 {
 174                     dpd.RemoveValueChanged(container, valueChangedEvent);
 175                 }
 176             }
 177         }
 178
 179         // IValueProvider Members
 180
 181         // <summary>
 182         // Sets the value of the property within the PropertyContainer
 183         // </summary>
 184         // <param name="value">Value to set</param>
 185         public void SetValue(string value)
 186         {
 187             _container.PropertyEntry.PropertyValue.StringValue = value;
 188         }
 189
 190         // <summary>
 191         // Scrolls the contained PropertyContainer into view, if it's within a scrolling control
 192         // </summary>
 193         public void ScrollIntoView()
 194         {
 195             _container.BringIntoView();
 196         }
 197
 198
 199         // IAutomationFocusChangedEventSource Members
 200         public void UnloadEventHook()
 201         {
 202             RemoveFocusEvents();
 203         }
 204
 205     }
 206 }