Xamarin.Forms-Samples/DataPages Customization/DataPages/App.xaml.cs

using Xamarin.Forms;

namespace DataPages
{
    public partial class App : Application
	{
		public App()
		{
			InitializeComponent();

			MainPage = new NavigationPage(new MainView());
		}

		protected override void OnStart()
		{
			// Handle when your app starts
		}

		protected override void OnSleep()
		{
			// Handle when your app sleeps
		}

		protected override void OnResume()
		{
			// Handle when your app resumes
		}
	}
}