UIView. Needs Display Set
Marks the view dirty and queues a redraw operation on it.
[Foundation.Export("setNeedsDisplay")] public virtual void SetNeedsDisplay ();
abstract member SetNeedsDisplay : unit -> unit override this.SetNeedsDisplay : unit -> unit
This method is invoked if the contents of the view need to be refreshed due to a change of state or geometry. Invoking this method will cause the Draw(CGRect) method to be invoked.
Alternatively you can use the SetNeedsDisplayInRect(CGRect) method to only mark a specific region of the view to be repainted.