mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/Base/Core/Internal/PropertyEditing/FromExpression/Framework/ValueEditors/ValueToIconConverter.cs

   1 // -------------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 // -------------------------------------------------------------------
   4 //From \\authoring\Sparkle\Source\1.0.1083.0\Common\Source\Framework\ValueEditors
   5 namespace System.Activities.Presentation.Internal.PropertyEditing.FromExpression.Framework.ValueEditors
   6 {
   7     using System;
   8     using System.Globalization;
   9     using System.Windows;
  10     using System.Windows.Data;
  11     using System.Windows.Media;
  12     using System.Diagnostics.CodeAnalysis;
  13     using System.Activities.Presentation;
  14
  15     // <summary>
  16     // Implement this interface to provide icons to the ValueToIconProvider
  17     // </summary>
  18     internal interface IIconProvider
  19     {
  20         ImageSource GetIconAsImageSource(object key, object parameter);
  21     }
  22
  23     // <summary>
  24     // Gets an Icon as a Brush from the IIconProvider passed in as the first object of a multibinding
  25     // using the second object as the key.
  26     // </summary>
  27
  28     [SuppressMessage("Microsoft.Performance", "CA1812:AvoidUninstantiatedInternalClasses")]
  29     internal class ValueToIconConverter : IMultiValueConverter
  30     {
  31         public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
  32         {
  33             if (values.Length == 2)
  34             {
  35                 IIconProvider iconProvider = values[0] as IIconProvider;
  36                 object objectToLookUp = values[1];
  37                 if (iconProvider != null && objectToLookUp != null)
  38                 {
  39                     return iconProvider.GetIconAsImageSource(objectToLookUp, parameter);
  40                 }
  41             }
  42
  43             return null;
  44         }
  45
  46         public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
  47         {
  48             throw FxTrace.Exception.AsError(new NotImplementedException(ExceptionStringTable.NoConvertBackForValueToIconConverter));
  49         }
  50     }
  51 }