public Popover(WindowFrame parent, Widget child, Position arrowPosition) { this.arrowPosition = arrowPosition; backend = WidgetRegistry.CreateBackend<IPopoverBackend> (GetType ()); backend.Init ((IWindowFrameBackend) WidgetRegistry.GetBackend (parent), (IWidgetBackend) WidgetRegistry.GetBackend (child), arrowPosition); backend.Closed += (sender, e) => { if (Closed != null) Closed (this, EventArgs.Empty); }; }