public virtual void UpdateCanReorderItems()
{
var canReorderItems = (ItemsView as ReorderableItemsView)?.CanReorderItems == true;
if (canReorderItems)
{
if (_itemTouchHelperCallback == null)
{
_itemTouchHelperCallback = new SimpleItemTouchHelperCallback();
}
if (_itemTouchHelper == null)
{
_itemTouchHelper = new ItemTouchHelper(_itemTouchHelperCallback);
_itemTouchHelper.AttachToRecyclerView(this);
}
_itemTouchHelperCallback.SetAdapter(ItemsViewAdapter as IItemTouchHelperAdapter);
}
else
{
if (_itemTouchHelper != null)
{
_itemTouchHelper.AttachToRecyclerView(null);
_itemTouchHelper.Dispose();
_itemTouchHelper = null;
}
if (_itemTouchHelperCallback != null)
{
_itemTouchHelperCallback.Dispose();
_itemTouchHelperCallback = null;
}
}
}
public virtual void TearDownOldElement(TItemsView oldElement)
{
// Stop listening for layout property changes
if (ItemsLayout != null)
{
ItemsLayout.PropertyChanged -= LayoutPropertyChanged;
}
// Stop listening for ScrollTo requests
oldElement.ScrollToRequested -= ScrollToRequested;
RemoveScrollListener();
if (ItemsViewAdapter != null)
{
// Stop watching for empty items or scroll adjustments
_emptyCollectionObserver.Stop(ItemsViewAdapter);
_itemsUpdateScrollObserver.Stop(ItemsViewAdapter);
// Unhook whichever adapter is active
SetAdapter(null);
_emptyViewAdapter?.Dispose();
ItemsViewAdapter?.Dispose();
}
if (_snapManager != null)
{
_snapManager.Dispose();
_snapManager = null;
}
if (_itemDecoration != null)
{
RemoveItemDecoration(_itemDecoration);
}
if (_itemTouchHelper != null)
{
_itemTouchHelper.AttachToRecyclerView(null);
_itemTouchHelper.Dispose();
_itemTouchHelper = null;
}
if (_itemTouchHelperCallback != null)
{
_itemTouchHelperCallback.Dispose();
_itemTouchHelperCallback = null;
}
}
