mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/Model/ModelTreeItemHelper.cs

   1 //----------------------------------------------------------------
   2 // <copyright company="Microsoft Corporation">
   3 //     Copyright (c) Microsoft Corporation.  All rights reserved.
   4 // </copyright>
   5 //----------------------------------------------------------------
   6
   7 namespace System.Activities.Presentation.Model
   8 {
   9     using System.Collections.Generic;
  10     using System.Linq;
  11     using System.Runtime;
  12
  13     // this class is to share common code among classes that implements IModelTreeItem, currently ModelItemImpl, ModelItemCollectionImpl and ModelItemDictionaryImpl
  14     internal class ModelTreeItemHelper
  15     {
  16         private List<BackPointer> extraPropertyBackPointers;
  17
  18         public ModelTreeItemHelper()
  19         {
  20             this.extraPropertyBackPointers = new List<BackPointer>();
  21         }
  22
  23         public List<BackPointer> ExtraPropertyBackPointers
  24         {
  25             get { return this.extraPropertyBackPointers; }
  26         }
  27
  28         public void RemoveExtraPropertyBackPointer(ModelItem parent, string propertyName)
  29         {
  30             Fx.Assert(parent != null, "parent should not be null");
  31             Fx.Assert(!string.IsNullOrEmpty(propertyName), "propertyName should not be null or empty");
  32
  33             BackPointer backPointer = this.extraPropertyBackPointers.FirstOrDefault<BackPointer>((bp) => bp.DestinationVertex == parent && propertyName == bp.PropertyName);
  34             if (backPointer != null)
  35             {
  36                 this.extraPropertyBackPointers.Remove(backPointer);
  37             }
  38             else
  39             {
  40                 Fx.Assert("BackPointer not found");
  41             }
  42         }
  43     }
  44 }