//
// Contact:
// Moonlight List (moonlight-list@lists.ximian.com)
//
// Copyright 2009 Novell, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
using System;
using System.Windows;
using System.Collections.Specialized;
using System.Windows.Controls.Primitives;
namespace System.Windows.Controls{
public abstract class VirtualizingPanel : Panel {
ItemContainerGenerator generator;
public IItemContainerGenerator ItemContainerGenerator {
get {
if (generator == null) {
ItemsControl owner = ItemsControl.GetItemsOwner (this);
if (owner == null)
throw new InvalidOperationException ("VirtualizingPanels must be in the Template of an ItemsControl in order to generate items");
generator = owner.ItemContainerGenerator;
generator.ItemsChanged += OnItemsChangedInternal;
}
return generator;
}
}
protected VirtualizingPanel ()
{
}
protected void AddInternalChild (UIElement child)
{
Children.Add (child);
}
protected void InsertInternalChild (int index, UIElement child)
{
Children.Insert (index, child);
}
protected void RemoveInternalChildRange (int index, int range)
{
for (int i = 0; i < range; i++)
Children.RemoveAt (index);
}
protected virtual void BringIndexIntoView (int index)
{
}
protected virtual void OnClearChildren ()
{
}
void OnItemsChangedInternal (object sender, ItemsChangedEventArgs args)
{
InvalidateMeasure ();
if (args.Action == NotifyCollectionChangedAction.Reset) {
Children.Clear ();
ItemContainerGenerator.RemoveAll ();
OnClearChildren ();
}
OnItemsChanged (sender, args);
}
protected virtual void OnItemsChanged (object sender, ItemsChangedEventArgs args)
{
}
}
}
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