private static void OnItemsSourcePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
MyVirtualizingPanel2 virtualizingPanel2 = d as MyVirtualizingPanel2;
if (virtualizingPanel2 == null)
{
return;
}
virtualizingPanel2.ClearItems();
INotifyCollectionChanged collection1 = e.OldValue as INotifyCollectionChanged;
if (collection1 != null)
{
virtualizingPanel2.UnhookCollectionChanged(collection1);
}
INotifyCollectionChanged collection2 = e.NewValue as INotifyCollectionChanged;
if (collection2 != null)
{
List <IVirtualizable> virtualizableList = new List <IVirtualizable>();
foreach (object obj in (IEnumerable)(collection2 as ICollection))
{
if (obj is IVirtualizable)
{
virtualizableList.Add(obj as IVirtualizable);
}
else if (virtualizingPanel2.CreateVirtItemFunc != null)
{
virtualizableList.Add(virtualizingPanel2.CreateVirtItemFunc(obj));
}
}
virtualizingPanel2.AddItems((IEnumerable <IVirtualizable>)virtualizableList);
virtualizingPanel2.HookUpCollectionChanged(collection2);
virtualizingPanel2.SubscribeOnEdit();
}
else
{
virtualizingPanel2.UnsubscribeOnEdit();
}
}
private void collection_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
MyVirtualizingPanel2 virtualizingPanel2 = this;
List <IVirtualizable> itemsToInsert = new List <IVirtualizable>();
if (e.NewItems != null)
{
foreach (object newItem in (IEnumerable)e.NewItems)
{
if (newItem is IVirtualizable)
{
itemsToInsert.Add(newItem as IVirtualizable);
}
else if (this.CreateVirtItemFunc != null)
{
itemsToInsert.Add(this.CreateVirtItemFunc(newItem));
}
}
}
List <IVirtualizable> virtualizableList1 = new List <IVirtualizable>();
if (e.OldItems != null)
{
foreach (object oldItem in (IEnumerable)e.OldItems)
{
if (oldItem is IVirtualizable)
{
virtualizableList1.Add(oldItem as IVirtualizable);
}
else if (e.OldStartingIndex >= 0 && e.OldStartingIndex < virtualizingPanel2.VirtualizableItems.Count)
{
IVirtualizable itemToBeRemoved = virtualizingPanel2.VirtualizableItems[e.OldStartingIndex];
virtualizingPanel2.RemoveItem(itemToBeRemoved);
}
}
}
if (this._isEditing)
{
this._addedWhileEdited.AddRange((IEnumerable <IVirtualizable>)itemsToInsert);
}
else if (e.Action == NotifyCollectionChangedAction.Add)
{
if (e.NewStartingIndex >= virtualizingPanel2.VirtualizableItems.Count)
{
virtualizingPanel2.AddItems((IEnumerable <IVirtualizable>)itemsToInsert);
}
else
{
virtualizingPanel2.InsertRemoveItems(e.NewStartingIndex, itemsToInsert, virtualizingPanel2.KeepScrollPositionWhenAddingItems, (IVirtualizable)null);
}
}
else if (e.Action == NotifyCollectionChangedAction.Reset)
{
virtualizingPanel2.ClearItems();
List <IVirtualizable> virtualizableList2 = new List <IVirtualizable>();
foreach (object obj in (IEnumerable)virtualizingPanel2.ItemsSource)
{
virtualizableList2.Add(obj is IVirtualizable ? obj as IVirtualizable : this.CreateVirtItemFunc(obj));
}
virtualizingPanel2.AddItems((IEnumerable <IVirtualizable>)virtualizableList2);
}
else
{
if (e.Action != NotifyCollectionChangedAction.Remove || virtualizableList1.Count <= 0)
{
return;
}
virtualizingPanel2.RemoveItem(virtualizableList1[0]);
}
}