private static void SetExtension(DependencyObject obj, PanelExtension value)
{
obj.SetValue(ExtensionProperty, value);
}
private static void OnItemsSourceChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
var panel = sender as Panel;
if (panel == null)
{
throw new InvalidOperationException("Codify.Controls.PanelExtension.ItemsSource property can only be attached to a System.Windows.Controls.Panel.");
}
var ext = GetExtension(panel);
if (ext == null)
{
SetExtension(panel, ext = new PanelExtension());
}
var oldSource = e.OldValue as INotifyCollectionChanged;
var newSource = e.NewValue as INotifyCollectionChanged;
if (oldSource != null)
{
oldSource.CollectionChanged -= ext.OnItemsSourceCollectionChanged;
panel.Children.Clear();
ext._delayItemsQueue.Clear();
}
if (newSource != null)
{
newSource.CollectionChanged += ext.OnItemsSourceCollectionChanged;
ext.AddItems(newSource as IEnumerable);
}
}