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using System;
using System.Collections;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls.Primitives;
namespace System.Windows.Controls
{
/// <summary>
/// The delegate type for handling a selection changed event
/// </summary>
public delegate void SelectionChangedEventHandler(
object sender,
SelectionChangedEventArgs e);
/// <summary>
/// The inputs to a selection changed event handler
/// </summary>
public class SelectionChangedEventArgs : RoutedEventArgs
{
#region Constructors
/// <summary>
/// The constructor for selection changed args
/// </summary>
/// <param name="id">The event ID for the event about to fire -- should probably be Selector.SelectionChangedEvent</param>
/// <param name="removedItems">The items that were unselected during this event</param>
/// <param name="addedItems">The items that were selected during this event</param>
public SelectionChangedEventArgs(
RoutedEvent id,
IList removedItems,
IList addedItems)
{
if (id == null)
throw new ArgumentNullException("id");
if (removedItems == null)
throw new ArgumentNullException("removedItems");
if (addedItems == null)
throw new ArgumentNullException("addedItems");
RoutedEvent = id;
_removedItems = new object[removedItems.Count];
removedItems.CopyTo(_removedItems, 0);
_addedItems = new object[addedItems.Count];
addedItems.CopyTo(_addedItems, 0);
}
internal SelectionChangedEventArgs(List<ItemsControl.ItemInfo> unselectedInfos, List<ItemsControl.ItemInfo> selectedInfos)
{
RoutedEvent = Selector.SelectionChangedEvent;
_removedItems = new object[unselectedInfos.Count];
for (int i=0; i<unselectedInfos.Count; ++i)
{
_removedItems[i] = unselectedInfos[i].Item;
}
_addedItems = new object[selectedInfos.Count];
for (int i=0; i<selectedInfos.Count; ++i)
{
_addedItems[i] = selectedInfos[i].Item;
}
_removedInfos = unselectedInfos;
_addedInfos = selectedInfos;
}
#endregion
#region Public Properties
/// <summary>
/// An IList containing the items that were unselected during this event
/// </summary>
public IList RemovedItems
{
get { return _removedItems; }
}
/// <summary>
/// An IList containing the items that were selected during this event
/// </summary>
public IList AddedItems
{
get { return _addedItems; }
}
#endregion
#region Internal Properties
/// <summary>
/// A list containing the ItemInfos that were unselected during this event
/// </summary>
internal List<ItemsControl.ItemInfo> RemovedInfos
{
get { return _removedInfos; }
}
/// <summary>
/// A list containing the ItemInfos that were selected during this event
/// </summary>
internal List<ItemsControl.ItemInfo> AddedInfos
{
get { return _addedInfos; }
}
#endregion
#region Protected Methods
/// <summary>
/// This method is used to perform the proper type casting in order to
/// call the type-safe SelectionChangedEventHandler delegate for the SelectionChangedEvent event.
/// </summary>
/// <param name="genericHandler">The handler to invoke.</param>
/// <param name="genericTarget">The current object along the event's route.</param>
protected override void InvokeEventHandler(Delegate genericHandler, object genericTarget)
{
SelectionChangedEventHandler handler = (SelectionChangedEventHandler)genericHandler;
handler(genericTarget, this);
}
#endregion
#region Data
private object[] _addedItems;
private object[] _removedItems;
private List<ItemsControl.ItemInfo> _addedInfos;
private List<ItemsControl.ItemInfo> _removedInfos;
#endregion
}
}
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