Why would auto-generated WP8 initialization code fail?

Question

The "RootFrame = " line in this code, all of which is auto-generated:

private void InitializePhoneApplication()
{
    if (phoneApplicationInitialized)
        return;

    // Create the frame but don't set it as RootVisual yet; this allows the splash
    // screen to remain active until the application is ready to render.
    RootFrame = new PhoneApplicationFrame();
    RootFrame.Navigated += CompleteInitializePhoneApplication;

    // Handle navigation failures
    RootFrame.NavigationFailed += RootFrame_NavigationFailed;

    // Handle reset requests for clearing the backstack
    RootFrame.Navigated += CheckForResetNavigation;

    // Ensure we don't initialize again
    phoneApplicationInitialized = true;
}

...fails with:

*System.TypeInitializationException was unhandled by user code HResult=-2146233036 Message=The type initializer for 'TaSLS_PhoneApp.App' threw an exception. Source=TaSLS_PhoneApp
TypeName=TaSLS_PhoneApp.App StackTrace: at TaSLS_PhoneApp.App.set_RootFrame(PhoneApplicationFrame value) at TaSLS_PhoneApp.App.InitializePhoneApplication() at TaSLS_PhoneApp.App..ctor() InnerException: System.NotImplementedException HResult=-2147467263 Message=The method or operation is not implemented. Source=Windows StackTrace: at Windows.Storage.ApplicationData.get_RoamingSettings() at TaSLS_PhoneApp.App..cctor() InnerException:*

Answer 1

The root cause isn't the generated code, but your code that it is calling...

TaSLS_PhoneApp.App.InitializePhoneApplication() at TaSLS_PhoneApp.App..ctor() InnerException: System.NotImplementedException HResult=-2147467263 Message=The method or operation is not implemented. Source=Windows StackTrace: at Windows.Storage.ApplicationData.get_RoamingSettings() at TaSLS_PhoneApp.App..cctor() InnerException:*

It looks like in your app's InitializePhoneApplication is calling a WinRT function which isn't implemented on Windows phone 8. See MSDN documentation at: http://msdn.microsoft.com/en-gb/library/windows/apps/windows.storage.applicationdata.roamingsettings.