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

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4
   5 namespace System.Activities.Presentation.Model
   6 {
   7     using System;
   8     using System.Collections.Generic;
   9     using System.Text;
  10     using System.Globalization;
  11     using System.Runtime;
  12     using System.Activities.Presentation.Services;
  13
  14     class PropertyChange : ModelChange
  15     {
  16         public ModelItem Owner { get; set; }
  17
  18         public string PropertyName { get; set; }
  19
  20         public ModelItem OldValue { get; set; }
  21
  22         public ModelItem NewValue { get; set; }
  23
  24         public ModelTreeManager ModelTreeManager { get; set; }
  25
  26         public override string Description
  27         {
  28             get
  29             {
  30                 return string.Format(CultureInfo.InvariantCulture, "{0} - {1}", SR.PropertyChangeEditingScopeDescription, this.PropertyName);
  31             }
  32         }
  33
  34         public override bool Apply()
  35         {
  36             Fx.Assert(this.ModelTreeManager != null, "Modeltreemanager cannot be null");
  37             Fx.Assert(this.Owner != null, "Owner modelitem cannot be null");
  38             Fx.Assert(!String.IsNullOrEmpty(this.PropertyName), " property name cannot be null or emptry");
  39             ModelPropertyImpl dataModelProperty = (ModelPropertyImpl)this.Owner.Properties[this.PropertyName];
  40             ModelItem oldValue = dataModelProperty.Value;
  41             if ((oldValue == null && this.NewValue == null) ||
  42                 (oldValue != null && this.NewValue != null && oldValue.GetCurrentValue().Equals(this.NewValue.GetCurrentValue())))
  43             {
  44                 return false;
  45             }
  46             dataModelProperty.SetValueCore(this.NewValue);
  47             ModelChangeInfo changeInfo = ModelChangeInfoImpl.CreatePropertyChanged(this.Owner, this.PropertyName, this.OldValue, this.NewValue);
  48             this.ModelTreeManager.NotifyPropertyChange(dataModelProperty, changeInfo);
  49             return true;
  50         }
  51
  52         public override Change GetInverse()
  53         {
  54             return new PropertyChange()
  55                 {
  56                     ModelTreeManager = this.ModelTreeManager,
  57                     Owner = this.Owner,
  58                     OldValue = this.NewValue,
  59                     NewValue = this.OldValue,
  60                     PropertyName = this.PropertyName
  61                 };
  62         }
  63     }
  64 }