Building a Windows 8 Metro App, Part 3: Listing 5

App.xaml.cs with Local Storage Management

using System;
using System.Threading.Tasks;
using Windows.ApplicationModel.Activation;
using Windows.ApplicationModel;
using Windows.UI.Xaml;
using VSMWinRTDemo.Storage;

namespace VSMWinRTDemo.UI
{
    partial class App
    {
        public App()
        {
            InitializeComponent();
            this.Suspending += new SuspendingEventHandler(App_Suspending);
        }

        async void App_Suspending(object sender, SuspendingEventArgs e)
        {
            SuspendingDeferral deferral = e.SuspendingOperation.GetDeferral();
            // save state to session
            await LocalStorage.Save();
            deferral.Complete();
        }

        async protected override void OnLaunched(LaunchActivatedEventArgs args)
        {
            if (args.PreviousExecutionState == ApplicationExecutionState.Terminated)
            {
                // restore last session
                await LocalStorage.Restore();
            }

            Window.Current.Content = new MainPage();
            Window.Current.Activate();
        }
    }
}

About the Author

Eric Vogel is a Sr. Software Developer at Kunz, Leigh, & Associates in Okemos, MI. He is the president of the Greater Lansing User Group for .NET. Eric enjoys learning about software architecture and craftsmanship, and is always looking for ways to create more robust and testable applications. Contact him at vogelvision@gmail.com.