private void SetupToolbar() { toolbar = new UIToolbar (new CoreGraphics.CGRect (0, 0, 0, 44)); textbox = new UITextView (CoreGraphics.CGRect.FromLTRB (0, 0, 0, 0)); textbox.BackgroundColor = UIColor.White; //textbox.Delegate = new TextDelegate (); textbox.Font = UIFont.SystemFontOfSize (UIFont.SystemFontSize); textbox.Layer.BorderColor = UIColor.FromRGB ((nfloat)200 / 255, (nfloat)200 / 255, (nfloat)200 / 255).CGColor; textbox.Layer.BorderWidth = (nfloat)0.5; textbox.Layer.CornerRadius = 5; textbox.ScrollsToTop = false; textbox.TextContainerInset = new UIEdgeInsets (3, 3, 3, 3); toolbar.AddSubview (textbox); sendButton = new UIButton (UIButtonType.System); sendButton.Enabled = false; sendButton.TitleLabel.Font = UIFont.BoldSystemFontOfSize (UIFont.SystemFontSize); sendButton.SetTitle ("Send", UIControlState.Normal); sendButton.SetTitleColor (UIColor.FromRGB (142, 142, 142), UIControlState.Disabled); sendButton.SetTitleColor (UIColor.FromRGB (1, 122, 255), UIControlState.Normal); sendButton.ContentEdgeInsets = new UIEdgeInsets (6, 6, 6, 6); //sendButton.AddTarget (sendAction, UIControlEvent.TouchUpInside); toolbar.AddSubview (sendButton); textbox.TranslatesAutoresizingMaskIntoConstraints = false; sendButton.TranslatesAutoresizingMaskIntoConstraints = false; toolbar.AddConstraint (NSLayoutConstraint.Create (textbox, NSLayoutAttribute.Left, NSLayoutRelation.Equal, toolbar, NSLayoutAttribute.Left, 1, 8)); toolbar.AddConstraint (NSLayoutConstraint.Create (textbox, NSLayoutAttribute.Top, NSLayoutRelation.Equal, toolbar, NSLayoutAttribute.Top, 1, 8)); toolbar.AddConstraint (NSLayoutConstraint.Create (textbox, NSLayoutAttribute.Right, NSLayoutRelation.Equal, sendButton, NSLayoutAttribute.Left, 1, -2)); toolbar.AddConstraint (NSLayoutConstraint.Create (textbox, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, toolbar, NSLayoutAttribute.Bottom, 1, -8)); toolbar.AddConstraint (NSLayoutConstraint.Create (sendButton, NSLayoutAttribute.Right, NSLayoutRelation.Equal, toolbar, NSLayoutAttribute.Right, 1, 0)); toolbar.AddConstraint (NSLayoutConstraint.Create (sendButton, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, toolbar, NSLayoutAttribute.Bottom, 1, -5)); }