mcs/class/System.Windows.Forms/System.Windows.Forms/PropertyManager.cs

   1 // Permission is hereby granted, free of charge, to any person obtaining
   2 // a copy of this software and associated documentation files (the
   3 // "Software"), to deal in the Software without restriction, including
   4 // without limitation the rights to use, copy, modify, merge, publish,
   5 // distribute, sublicense, and/or sell copies of the Software, and to
   6 // permit persons to whom the Software is furnished to do so, subject to
   7 // the following conditions:
   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2005 Novell, Inc.
  21 //
  22 // Authors:
  23 //      Jackson Harper  jackson@ximian.com
  24
  25 using System;
  26 using System.Collections;
  27 using System.ComponentModel;
  28
  29 namespace System.Windows.Forms {
  30
  31         public class PropertyManager : BindingManagerBase {
  32
  33                 internal string property_name;
  34                 private PropertyDescriptor prop_desc;
  35                 private object data_source;
  36                 private EventDescriptor changed_event;
  37                 private EventHandler property_value_changed_handler;
  38
  39                 public PropertyManager() {
  40                 }
  41
  42                 internal PropertyManager (object data_source)
  43                 {
  44                         SetDataSource (data_source);
  45                 }
  46
  47                 internal PropertyManager (object data_source, string property_name)
  48                 {
  49                         this.property_name = property_name;
  50
  51                         SetDataSource (data_source);
  52                 }
  53
  54                 internal void SetDataSource (object new_data_source)
  55                 {
  56                         if (changed_event != null)
  57                                 changed_event.RemoveEventHandler (data_source, property_value_changed_handler);
  58
  59                         data_source = new_data_source;
  60
  61                         if (property_name != null) {
  62                                 prop_desc = TypeDescriptor.GetProperties (data_source).Find (property_name, true);
  63
  64                                 if (prop_desc == null)
  65                                         return;
  66
  67                                 changed_event = TypeDescriptor.GetEvents (data_source).Find (property_name + "Changed", false);
  68                                 if (changed_event != null) {
  69                                         property_value_changed_handler = new EventHandler (PropertyValueChanged);
  70                                         changed_event.AddEventHandler (data_source, property_value_changed_handler);
  71                                 }
  72                         }
  73                 }
  74
  75                 void PropertyValueChanged (object sender, EventArgs args)
  76                 {
  77                         OnCurrentChanged (args);
  78                 }
  79
  80                 public override object Current {
  81                         get { return prop_desc == null ? data_source : prop_desc.GetValue (data_source); }
  82                 }
  83
  84                 public override int Position {
  85                         get { return 0; }
  86                         set { /* Doesn't do anything on MS" */ }
  87                 }
  88
  89                 public override int Count {
  90                         get { return 1; }
  91                 }
  92
  93                 public override void AddNew ()
  94                 {
  95                         throw new NotSupportedException ("AddNew is not supported for property to property binding");
  96                 }
  97
  98                 public override void CancelCurrentEdit ()
  99                 {
 100                         IEditableObject editable = data_source as IEditableObject;
 101                         if (editable == null)
 102                                 return;
 103                         editable.CancelEdit ();
 104
 105                         PushData ();
 106                 }
 107
 108                 public override void EndCurrentEdit ()
 109                 {
 110                         PullData ();
 111
 112                         IEditableObject editable = data_source as IEditableObject;
 113                         if (editable == null)
 114                                 return;
 115                         editable.EndEdit ();
 116                 }
 117
 118                 // Hide this method from the 2.0 public API
 119                 internal override PropertyDescriptorCollection GetItemPropertiesInternal ()
 120                 {
 121                         return TypeDescriptor.GetProperties (data_source);
 122                 }
 123
 124                 public override void RemoveAt (int index)
 125                 {
 126                         throw new NotSupportedException ("RemoveAt is not supported for property to property binding");
 127                 }
 128
 129                 public override void ResumeBinding ()
 130                 {
 131                 }
 132
 133                 public override void SuspendBinding ()
 134                 {
 135                 }
 136
 137                 internal override bool IsSuspended {
 138                         get { return data_source == null; }
 139                 }
 140
 141                 protected internal override string GetListName (ArrayList listAccessors)
 142                 {
 143                         return String.Empty;
 144                 }
 145
 146                 [MonoTODO ("Stub, does nothing")]
 147                 protected override void UpdateIsBinding ()
 148                 {
 149                 }
 150
 151                 protected internal override void OnCurrentChanged (EventArgs ea)
 152                 {
 153                         PushData ();
 154
 155                         if (onCurrentChangedHandler != null) {
 156                                 onCurrentChangedHandler (this, ea);
 157                         }
 158                 }
 159
 160                 protected override void OnCurrentItemChanged (EventArgs ea)
 161                 {
 162                         throw new NotImplementedException ();
 163                 }
 164         }
 165 }
 166