App.xaml.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using WhimsyEarlierLiteracy.ViewModel;
using Windows.ApplicationModel;
using Windows.ApplicationModel.Activation;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;

// The Blank Application template is documented at http://go.microsoft.com/fwlink/?LinkId=234227

namespace WhimsyEarlierLiteracy
{
    sealed partial class App : Application
    {
        public App()
        {
            this.InitializeComponent();
            this.Suspending += OnSuspending;
        }

        protected override void OnLaunched(LaunchActivatedEventArgs args)
        {
            Frame rootFrame = Window.Current.Content as Frame;
            DispatcherHelper.Dispatcher = Window.Current.Dispatcher;

            if (rootFrame == null)
            {
                rootFrame = new Frame();
                if (args.PreviousExecutionState == ApplicationExecutionState.Terminated)
                {
                    //TODO: Load state from previously suspended application
                }

                Window.Current.Content = rootFrame;
            }

            if (rootFrame.Content == null)
            {
                if (!rootFrame.Navigate(typeof(MainPage), args.Arguments))
                {
                    throw new Exception("Failed to create initial page");
                }
            }
            Window.Current.Activate();
        }

        /// <summary>
        /// Invoked when application execution is being suspended.  Application state is saved
        /// without knowing whether the application will be terminated or resumed with the contents
        /// of memory still intact.
        /// </summary>
        /// <param name="sender">The source of the suspend request.</param>
        /// <param name="e">Details about the suspend request.</param>
        private void OnSuspending(object sender, SuspendingEventArgs e)
        {
            var deferral = e.SuspendingOperation.GetDeferral();
            deferral.Complete();
        }
    }
}