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:
9 // The above copyright notice and this permission notice shall be
10 // included in all copies or substantial portions of the Software.
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.
20 // Copyright (c) 2007 Novell, Inc. (http://www.novell.com)
21 // Copyright 2011 Xamarin Inc.
24 // Chris Toshok (toshok@novell.com)
25 // Brian O'Keefe (zer0keefie@gmail.com)
26 // Marek Safar (marek.safar@gmail.com)
30 using System
.Collections
.Generic
;
31 using System
.Collections
.Specialized
;
32 using System
.ComponentModel
;
33 using System
.Runtime
.CompilerServices
;
35 namespace System
.Collections
.ObjectModel
39 [TypeForwardedFrom (Consts
.WindowsBase_3_0
)]
41 public class ObservableCollection
<T
> : Collection
<T
>, INotifyCollectionChanged
, INotifyPropertyChanged
{
43 private class Reentrant
: IDisposable
{
44 private int count
= 0;
62 get { return count > 0; }
66 private Reentrant reentrant
= new Reentrant ();
68 public ObservableCollection ()
72 public ObservableCollection (IEnumerable
<T
> collection
)
74 if (collection
== null)
75 throw new ArgumentNullException ("collection");
77 foreach (var item
in collection
)
81 public ObservableCollection (List
<T
> list
)
82 : base (list
!= null ? new List
<T
> (list
) : null)
86 public virtual event NotifyCollectionChangedEventHandler CollectionChanged
;
87 protected virtual event PropertyChangedEventHandler PropertyChanged
;
89 event PropertyChangedEventHandler INotifyPropertyChanged
.PropertyChanged
{
90 add { this.PropertyChanged += value; }
91 remove { this.PropertyChanged -= value; }
94 protected IDisposable
BlockReentrancy ()
100 protected void CheckReentrancy ()
102 NotifyCollectionChangedEventHandler eh
= CollectionChanged
;
104 // Only have a problem if we have more than one event listener.
105 if (reentrant
.Busy
&& eh
!= null && eh
.GetInvocationList ().Length
> 1)
106 throw new InvalidOperationException ("Cannot modify the collection while reentrancy is blocked.");
109 protected override void ClearItems ()
115 OnCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction
.Reset
));
116 OnPropertyChanged (new PropertyChangedEventArgs ("Count"));
117 OnPropertyChanged (new PropertyChangedEventArgs ("Item[]"));
120 protected override void InsertItem (int index
, T item
)
124 base.InsertItem (index
, item
);
126 OnCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction
.Add
, item
, index
));
127 OnPropertyChanged (new PropertyChangedEventArgs ("Count"));
128 OnPropertyChanged (new PropertyChangedEventArgs ("Item[]"));
131 public void Move (int oldIndex
, int newIndex
)
133 MoveItem (oldIndex
, newIndex
);
136 protected virtual void MoveItem (int oldIndex
, int newIndex
)
140 T item
= Items
[oldIndex
];
141 base.RemoveItem (oldIndex
);
142 base.InsertItem (newIndex
, item
);
144 OnCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction
.Move
, item
, newIndex
, oldIndex
));
145 OnPropertyChanged (new PropertyChangedEventArgs ("Item[]"));
148 protected virtual void OnCollectionChanged (NotifyCollectionChangedEventArgs e
)
150 NotifyCollectionChangedEventHandler eh
= CollectionChanged
;
153 // Make sure that the invocation is done before the collection changes,
154 // Otherwise there's a chance of data corruption.
155 using (BlockReentrancy ()) {
161 protected virtual void OnPropertyChanged (PropertyChangedEventArgs e
)
163 PropertyChangedEventHandler eh
= PropertyChanged
;
169 protected override void RemoveItem (int index
)
173 T item
= Items
[index
];
175 base.RemoveItem (index
);
177 OnCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction
.Remove
, item
, index
));
178 OnPropertyChanged (new PropertyChangedEventArgs ("Count"));
179 OnPropertyChanged (new PropertyChangedEventArgs ("Item[]"));
182 protected override void SetItem (int index
, T item
)
186 T oldItem
= Items
[index
];
188 base.SetItem (index
, item
);
190 OnCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction
.Replace
, item
, oldItem
, index
));
191 OnPropertyChanged (new PropertyChangedEventArgs ("Item[]"));