/// <summary>
/// Returns the item at the specified zero-based index in this view.
/// </summary>
/// <param name="index">The zero-based index at which the item is located.</param>
/// <returns>The item at the specified zero-based index in this view.</returns>
public override Object GetItemAt(Int32 index)
{
// Make sure the index is within range. For performance reasons there is no check for the upper bounds of an IEnumerable collection.
if (index < 0)
{
throw new ArgumentOutOfRangeException("index");
}
// See if we can extract an item from a collection view.
CollectionView collectionView = this.currentView as CollectionView;
if (collectionView != null)
{
return(collectionView.GetItemAt(index));
}
// See if there is a ViewableCollection class that can be used to return the number of items in the collection.
ViewableCollection viewableCollection = this.currentView as ViewableCollection;
if (viewableCollection != null)
{
return(viewableCollection.GetItemAt(index));
}
// At this point, we can't extract an item from the current collection view.
return(null);
}
///// <summary>
/////
///// </summary>
///// <param name="notifyCollectionChangedEventArgs"></param>
//protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs notifyCollectionChangedEventArgs)
//{
// if (this.CollectionChanged != null)
// this.CollectionChanged(this, notifyCollectionChangedEventArgs);
// base.OnCollectionChanged(notifyCollectionChangedEventArgs);
//}
/// <summary>
/// Returns a value that indicates whether the specified item belongs to this view.
/// </summary>
/// <param name="item">The object to test.</param>
/// <returns>true to indicate that the specified item belongs to this view or there is no filter set on this collection view; otherwise, false.</returns>
public override Boolean PassesFilter(Object item)
{
// Test whether the value in the inner collection can pass the filters placed on it.
CollectionView collectionView = this.currentView as CollectionView;
if (collectionView != null)
{
return(collectionView.PassesFilter(item));
}
// See if there is a ViewableCollection class that can be used to return the number of items in the collection.
ViewableCollection viewableCollection = this.currentView as ViewableCollection;
if (viewableCollection != null)
{
return(viewableCollection.PassesFilter(item));
}
// If there is no class available to check the filter, then the filter operation will fail.
return(false);
}