View

            View.BackgroundColor = UIColor.LightGray;
            Title = "Tip Calculator";
            var statusBarHeight = UIApplication.SharedApplication.StatusBarFrame.Height;
            var topPadding = UIApplication.SharedApplication.Windows[0].SafeAreaInsets.Top + statusBarHeight;

            totalAmount = new UITextField()
            {
                Frame = new CGRect(20, topPadding + 20, View.Bounds.Width - 40, 35),
                KeyboardType = UIKeyboardType.DecimalPad,
                BorderStyle = UITextBorderStyle.RoundedRect,
                Placeholder = "Enter Total Amount",
                AutoresizingMask = UIViewAutoresizing.FlexibleWidth
        };

            calcButton = new UIButton(UIButtonType.Custom)
            {
                Frame = new CGRect(20, 71 + topPadding, View.Bounds.Width - 40, 45),
                BackgroundColor = UIColor.FromRGB(0, 0.5f, 0),
                AutoresizingMask = UIViewAutoresizing.FlexibleWidth
            };
            calcButton.SetTitle("Calculate", UIControlState.Normal);

            resultLabel = new UILabel()
            {
                Frame = new CGRect(20, 124 + topPadding, View.Bounds.Width - 40, 40),
                TextColor = UIColor.Blue,
                TextAlignment = UITextAlignment.Center,
                Font = UIFont.SystemFontOfSize(24),
                Text = "Tip is $0.00",
                AutoresizingMask = UIViewAutoresizing.FlexibleWidth
            };
            navButton = new UIButton(UIButtonType.Custom)
            {
                Frame = new CGRect(20, 170 + topPadding, View.Bounds.Width - 40, 45),
                BackgroundColor = UIColor.FromRGB(0, 0.5f, 0),
                AutoresizingMask = UIViewAutoresizing.FlexibleWidth
            };
            navButton.SetTitle("Navigate", UIControlState.Normal);
            View.AddSubviews(totalAmount, calcButton, resultLabel, navButton);