DisplayAlertUITest.cs

using System;

using Xamarin.Forms;

namespace DisplayAlertUITest
{
	public class App : Application
	{
		public App()
		{
			// The root page of your application
			var content = new ContentPage
			{
				Title = "DisplayAlertUITest",
				Content = new StackLayout
				{
					VerticalOptions = LayoutOptions.Center,
					Children = {
						new Label {
							HorizontalTextAlignment = TextAlignment.Center,
							Text = "Welcome to Xamarin Forms!"
						}
					}
				}
			};

			MainPage = new NavigationPage(content);
		}

		protected override void OnStart()
		{
			MainPage.DisplayAlert("Title", "Message", "OK");
		}
	}
}