ModalWindow.cs

//code doesn't throw but the modal window isn't displayed

partial void openModalWindow (MonoTouch.UIKit.UIButton sender)
		{
			ModalViewController modal = new ModalSpike.ModalViewController
			{
				ModalTransitionStyle = UIModalTransitionStyle.CoverVertical,
				ModalPresentationStyle = UIModalPresentationStyle.FormSheet
			};
			
			this.navigationController.PresentModalViewController(modal, true);
		}