mcs/class/System.ComponentModel.Composition/Tests/ComponentModelUnitTest/System/ComponentModel/Composition/Factories/CatalogFactory.FilteredComposablePartCatalog.cs

   1 // -----------------------------------------------------------------------\r
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.\r
   3 // -----------------------------------------------------------------------\r
   4 using System;\r
   5 using System.ComponentModel.Composition.Primitives;\r
   6 using System.ComponentModel.Composition.Hosting;\r
   7 using System.Linq;\r
   8 using System.Linq.Expressions;\r
   9 \r
  10 namespace System.ComponentModel.Composition.Factories\r
  11 {\r
  12     partial class CatalogFactory\r
  13     {\r
  14         public class FilteredCatalog : ComposablePartCatalog, INotifyComposablePartCatalogChanged\r
  15         {\r
  16             private readonly ComposablePartCatalog _inner;\r
  17             private readonly INotifyComposablePartCatalogChanged _innerNotifyChange;\r
  18             private readonly IQueryable<ComposablePartDefinition> _partsQuery;\r
  19 \r
  20             public FilteredCatalog(ComposablePartCatalog inner,\r
  21                                    Func<ComposablePartDefinition, bool> filter)\r
  22             {\r
  23                 _inner = inner;\r
  24                 _innerNotifyChange = inner as INotifyComposablePartCatalogChanged;\r
  25                 _partsQuery = inner.Parts.Where(filter).AsQueryable();\r
  26             }\r
  27 \r
  28             public override IQueryable<ComposablePartDefinition> Parts\r
  29             {\r
  30                 get\r
  31                 {\r
  32                     return _partsQuery;\r
  33                 }\r
  34             }\r
  35 \r
  36             public event EventHandler<ComposablePartCatalogChangeEventArgs> Changed\r
  37             {\r
  38                 add\r
  39                 {\r
  40                     if (_innerNotifyChange != null)\r
  41                         _innerNotifyChange.Changed += value;\r
  42                 }\r
  43                 remove\r
  44                 {\r
  45                     if (_innerNotifyChange != null)\r
  46                         _innerNotifyChange.Changed -= value;\r
  47                 }\r
  48             }\r
  49 \r
  50             public event EventHandler<ComposablePartCatalogChangeEventArgs> Changing\r
  51             {\r
  52                 add\r
  53                 {\r
  54                     if (_innerNotifyChange != null)\r
  55                         _innerNotifyChange.Changing += value;\r
  56                 }\r
  57                 remove\r
  58                 {\r
  59                     if (_innerNotifyChange != null)\r
  60                         _innerNotifyChange.Changing -= value;\r
  61                 }\r
  62             }\r
  63         }\r
  64     }\r
  65 }\r