Xamarin Visual Format Language Example for iOS Auto Layouts

XamVisualFormatLan

using System;
using MonoTouch.UIKit;
using MonoTouch.CoreGraphics;
using MonoTouch.Foundation;

namespace Code
{
	public class MyViewController : UIViewController
	{
		UIButton button1, button2, button3, button4;

		public MyViewController ()
		{

		}

		public override void ViewDidLoad ()
		{
			base.ViewDidLoad ();

			this.View.BackgroundColor = UIColor.White;

			CreateButtons ();

			VisualFormat ();
		}

		UIButton CreateButton (string title)
		{
			var button = UIButton.FromType (UIButtonType.RoundedRect);
			button.SetTitle (title, UIControlState.Normal);
			button.Layer.BorderWidth = 1;
			button.TranslatesAutoresizingMaskIntoConstraints = false;

			return button;
		}

		void CreateButtons ()
		{
			button1 = CreateButton ("Button1");
			button2 = CreateButton ("Button2");
			button3 = CreateButton ("Button3");
			button4 = CreateButton ("Button4");

			this.View.Add (button1);
			this.View.Add (button2);
			this.View.Add (button3);
			this.View.Add (button4);
		}

		void VisualFormat ()
		{
			var keys = new object [] { "button1", "button2", "button3", "button4" };
			var objects = new object [] { button1, button2, button3, button4 };
			var myViews = NSDictionary.FromObjectsAndKeys (objects, keys);
			var height = new NSDictionary ("height", 50.0);

			//horizontal layout
			this.View.AddConstraints( NSLayoutConstraint.FromVisualFormat(@"|-[button1(button2)]-[button2(button3)]-[button3(button4)]-[button4]-|",
				NSLayoutFormatOptions.AlignAllTop | NSLayoutFormatOptions.AlignAllBottom, height, myViews));

			//vertical layout
			this.View.AddConstraints(NSLayoutConstraint.FromVisualFormat(@"V:[button1(height)]-|", 
				0, height, myViews));

		}
	}
}