public App() { this.Startup += this.Application_Startup; this.Exit += this.Application_Exit; this.UnhandledException += this.Application_UnhandledException; if (!UseMeF) { var locator = new Locator(); var initializer = new ViewModelInitializer(locator.GetViewModel); } else { var initializer = new MefViewModelInitializer(); var container = new CompositionContainer(new AssemblyCatalog(typeof(App).Assembly)); MefLocator.SetCompositionContainer(container); } InitializeComponent(); }