Create a TabBar

[Register ("AppDelegate")]public partial class AppDelegate : UIApplicationDelegate{// class-level declarationsUIWindow window;TabBarController tabBarController;public override bool FinishedLaunching (UIApplication app, NSDictionary options){// create a new window instance based on the screen sizewindow = new UIWindow (UIScreen.MainScreen.Bounds);tabBarController = new TabBarController();// If you have defined a view, add it here:window.RootViewController = tabBarController;// make the window visiblewindow.MakeKeyAndVisible ();return true;}}

public class TabBarController : UITabBarController {UIViewController tab1, tab2, tab3;public TabBarController (){tab1 = new UIViewController();tab1.Title = "Green";tab1.View.BackgroundColor = UIColor.Green;//===========================UIButton btn = new UIButton (UIButtonType.RoundedRect);btn.Bounds = new RectangleF (100, 80, 200, 150);btn.SetTitle ("tewat", UIControlState.Normal);tab1.View.Add (btn);btn.TouchUpInside += delegate {//...};//===========================tab2 = new UIViewController();tab2.Title = "Orange";tab2.View.BackgroundColor = UIColor.Orange;tab3 = new UIViewController();tab3.Title = "Red";tab3.View.BackgroundColor = UIColor.Red;#region Additional Info//tab1.TabBarItem = new UITabBarItem (UITabBarSystemItem.History, 0); // sets image AND text//tab2.TabBarItem = new UITabBarItem ("Orange", UIImage.FromFile("Images/first.png"), 1);//tab3.TabBarItem = new UITabBarItem ();//tab3.TabBarItem.Image = UIImage.FromFile("Images/second.png");//tab3.TabBarItem.Title = "Rouge"; // this overrides tab3.Title set above//tab3.TabBarItem.BadgeValue = "4";//tab3.TabBarItem.Enabled = false;#endregionvar tabs = new UIViewController[] {tab1, tab2, tab3};this.ViewControllers =tabs;//this.SelectedViewController = tab1; // normally you would default to the left-most tab (ie. tab1)}}