internal void Invalidate() { if (treeView == null || !treeView.IsHandleCreated) { return; } RectangleF bounds = Bounds; if (bounds != Rectangle.Empty) { // Include the focus rectangle. bounds = new Rectangle(0, (int)bounds.Y - 1, (int)bounds.Right + 2, (int)bounds.Height + 2); treeView.Invalidate(TreeViewEx.RectIFromRectF(bounds)); } }