private async void loginButton_Click(object sender, RoutedEventArgs e) { String password = PasswordLogin.Password; handleDatabase = new HandleDatabase(); validUser = handleDatabase.getUser(userNameLogin, password); if (validUser) { await this.ShowMessageAsync("Welcome", "Welcome to IDB", MessageDialogStyle.Affirmative); MainMenu main = new MainMenu(); main.Show(); this.Close(); } else { await this.ShowMessageAsync("Error", "Error, please try again", MessageDialogStyle.Affirmative); } }