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8c763fb | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 | // Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.ComponentModel;
namespace Microsoft.Management.UI.Internal
{
/// <summary>
/// Represents a read-only ObservableCollection which also implement IAsyncProgress.
/// </summary>
/// <typeparam name="T">The type held by the collection.</typeparam>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.MSInternal", "CA903:InternalNamespaceShouldNotContainPublicTypes")]
public class ReadOnlyObservableAsyncCollection<T> :
ReadOnlyCollection<T>,
IAsyncProgress,
INotifyPropertyChanged, INotifyCollectionChanged
{
#region Private fields
private IAsyncProgress asyncProgress;
#endregion Private fields
#region Constructors
/// <summary>
/// The constructor.
/// </summary>
/// <param name="list">The collection with which to create this instance of the ReadOnlyObservableAsyncCollection class.
/// The object must also implement IAsyncProgress, INotifyCollectionChanged and INotifyPropertyChanged.</param>
public ReadOnlyObservableAsyncCollection(IList<T> list)
: base(list)
{
this.asyncProgress = list as IAsyncProgress;
((INotifyCollectionChanged)this.Items).CollectionChanged += this.HandleCollectionChanged;
((INotifyPropertyChanged)this.Items).PropertyChanged += this.HandlePropertyChanged;
}
#endregion Constructors
#region Events
/// <summary>
/// Occurs when the collection changes, either by adding or removing an item.
/// </summary>
/// <remarks>
/// see <see cref="INotifyCollectionChanged"/>
/// </remarks>
public event NotifyCollectionChangedEventHandler CollectionChanged;
/// <summary>
/// Occurs when a property changes.
/// </summary>
/// <remarks>
/// see <see cref="INotifyPropertyChanged"/>
/// </remarks>
public event PropertyChangedEventHandler PropertyChanged;
#endregion Events
#region IAsyncProgress
/// <summary>
/// Gets a value indicating whether the async operation is currently running.
/// </summary>
public bool OperationInProgress
{
get
{
if (this.asyncProgress == null)
{
return false;
}
else
{
return this.asyncProgress.OperationInProgress;
}
}
}
/// <summary>
/// Gets the error for the async operation. This field is only valid if
/// OperationInProgress is false. null indicates there was no error.
/// </summary>
public Exception OperationError
{
get
{
if (this.asyncProgress == null)
{
return null;
}
else
{
return this.asyncProgress.OperationError;
}
}
}
#endregion IAsyncProgress
#region Private Methods
private void OnCollectionChanged(NotifyCollectionChangedEventArgs args)
{
NotifyCollectionChangedEventHandler eh = this.CollectionChanged;
if (eh != null)
{
eh(this, args);
}
}
private void OnPropertyChanged(PropertyChangedEventArgs args)
{
PropertyChangedEventHandler eh = this.PropertyChanged;
if (eh != null)
{
eh(this, args);
}
}
// forward CollectionChanged events from the base list to our listeners
private void HandleCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
this.OnCollectionChanged(e);
}
// forward PropertyChanged events from the base list to our listeners
private void HandlePropertyChanged(object sender, PropertyChangedEventArgs e)
{
this.OnPropertyChanged(e);
}
#endregion Private Methods
}
}
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