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

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4 namespace System.Activities.Presentation.Internal.PropertyEditing
   5 {
   6     using System;
   7     using System.Collections.Generic;
   8     using System.Diagnostics;
   9     using System.Text;
  10
  11     using System.Activities.Presentation.Internal.PropertyEditing.State;
  12
  13     // <summary>
  14     // Simple wrapper around a dictionary of PropertyStates keyed by the property names.
  15     // </summary>
  16     internal class PropertyStateContainer : PersistedStateContainer
  17     {
  18
  19         private static PropertyStateContainer _instance;
  20
  21         // The ctor is private because we use this class as a singleton
  22         private PropertyStateContainer()
  23         {
  24         }
  25
  26         // <summary>
  27         // Gets a static instance of this class
  28         // </summary>
  29         public static PropertyStateContainer Instance
  30         {
  31             get {
  32                 if (_instance == null)
  33                 {
  34                     _instance = new PropertyStateContainer();
  35                 }
  36
  37                 return _instance;
  38             }
  39         }
  40
  41         // <summary>
  42         // Gets the PropertyState for the specified category.  If one does not exist
  43         // yet, it will be created automatically, guaranteeing a non-null return value.
  44         // </summary>
  45         // <param name="propertyName">Name of the property itself</param>
  46         // <returns>A non-null instance of PropertyState</returns>
  47         public PropertyState GetPropertyState(string propertyName)
  48         {
  49             return (PropertyState)this.GetState(propertyName);
  50         }
  51
  52         // <summary>
  53         // Creates a default state object based on the specified key
  54         // </summary>
  55         // <param name="key">Key of the state object</param>
  56         // <returns>Default state object</returns>
  57         protected override PersistedState CreateDefaultState(object key)
  58         {
  59             return new PropertyState(key as string);
  60         }
  61
  62         // <summary>
  63         // Deserializes the specified string value into a state object
  64         // </summary>
  65         // <param name="serializedValue">Serialized value of the state object</param>
  66         // <returns>Deserialized instance of the state object</returns>
  67         protected override PersistedState DeserializeState(string serializedValue)
  68         {
  69             return PropertyState.Deserialize(serializedValue);
  70         }
  71     }
  72 }