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

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4 namespace System.Activities.Presentation.Internal.PropertyEditing
   5 {
   6     using System.Diagnostics.CodeAnalysis;
   7     using System.Windows;
   8
   9     using System.Activities.Presentation.PropertyEditing;
  10
  11     using Blend = System.Activities.Presentation.Internal.PropertyEditing.FromExpression.Framework.PropertyInspector;
  12     using System.Activities.Presentation.Internal.PropertyEditing.Selection;
  13     using System.Activities.Presentation.Internal.PropertyEditing.State;
  14
  15     // <summary>
  16     // Container for PropertyContainers - fancy wrapper for ItemsControl that eliminates the need
  17     // for intermediate ContentControls.
  18     //
  19     // This class is referenced from XAML
  20     // </summary>
  21     [SuppressMessage("Microsoft.Performance", "CA1812:AvoidUninstantiatedInternalClasses")]
  22     internal class CiderStandardCategoryLayout : Blend.StandardCategoryLayout
  23     {
  24
  25         protected override void PrepareContainerForItemOverride(DependencyObject element, object item)
  26         {
  27             base.PrepareContainerForItemOverride(element, item);
  28
  29             if (element != null)
  30             {
  31                 PropertyEntry property = ((PropertyContainer)element).PropertyEntry;
  32
  33                 if (property != null)
  34                 {
  35                     // Make each PropertyContainer its own selection stop
  36                     PropertySelection.SetSelectionStop(element, new PropertySelectionStop(property));
  37                 }
  38
  39                 PropertyContainer container = element as PropertyContainer;
  40                 if (container != null)
  41                 {
  42                     container.Loaded += new RoutedEventHandler(OnPropertyContainerLoaded);
  43                 }
  44             }
  45         }
  46
  47         private void OnPropertyContainerLoaded(object sender, RoutedEventArgs e)
  48         {
  49             PropertyContainer container = sender as PropertyContainer;
  50             if (container != null)
  51             {
  52
  53                 // When each PropertyContainer gets loaded, restore its ActiveEditMode
  54                 // based on stored state
  55                 //
  56                 container.ActiveEditMode = PropertyActiveEditModeStateContainer.Instance.GetActiveEditMode(container.PropertyEntry);
  57
  58                 // HACK: Here, we would want to hook into the ActiveEditModeChanged
  59                 // event to store (and restore) the correct expaded state to each
  60                 // value editor across domain reloads.  However, we already shipped
  61                 // System.Activities.Presentation.dll which contains the PropertyContainer
  62                 // class and it's dangerous to add new events to this assembly at this
  63                 // point.  Once we refactor MWD, we need to add this new event and
  64                 // simplify this code.  In the meanwhile, we can cheat and accomplish
  65                 // the same effect by listening to SizeChanged event, which _will_
  66                 // change when the expanded value editor is pinned down.  It will also
  67                 // change at other times (user-triggered resize events, etc.), but
  68                 // it shouldn't cause any noticeable perf degradation.
  69                 //
  70                 container.SizeChanged += new SizeChangedEventHandler(OnPropertyContainerSizeChanged);
  71                 container.Unloaded += new RoutedEventHandler(OnPropertyContainerUnloaded);
  72             }
  73         }
  74
  75         // When the size of each PropertyContainer changes, assume that ActiveEditMode
  76         // may have been changed and record its current state
  77         //
  78         private void OnPropertyContainerSizeChanged(object sender, SizeChangedEventArgs e)
  79         {
  80             PropertyContainer container = sender as PropertyContainer;
  81             if (container != null && container.IsLoaded)
  82             {
  83                 PropertyActiveEditModeStateContainer.Instance.StoreActiveEditMode(container.PropertyEntry, container.ActiveEditMode);
  84             }
  85         }
  86
  87         // When each PropertyContainer gets unloaded, stop listening to all events so
  88         // that it can be garbage collected
  89         //
  90         private void OnPropertyContainerUnloaded(object sender, RoutedEventArgs e)
  91         {
  92             PropertyContainer container = sender as PropertyContainer;
  93
  94             if (container != null)
  95             {
  96                 container.SizeChanged -= new SizeChangedEventHandler(OnPropertyContainerSizeChanged);
  97                 container.Loaded -= new RoutedEventHandler(OnPropertyContainerLoaded);
  98                 container.Unloaded -= new RoutedEventHandler(OnPropertyContainerUnloaded);
  99             }
 100         }
 101     }
 102 }