private void Preloader_ContentRendered(object sender, EventArgs ev) { Dispatcher.BeginInvoke((Action)(() => { ConfigureIOC(); _mainWindow = ServiceCollection.Resolve <MainWindow>(); _mainWindow.ContentRendered += delegate { _mainWindow.Activate(); _preloader.Dispatcher.BeginInvoke((Action)(() => { _preloader.Close(); _preloader.Dispatcher.BeginInvokeShutdown(DispatcherPriority.Normal); })); }; _mainWindow.Show(); })); }