private async Task ManageButtons(object sender) { _timer.Cancel(); var backgroundCorrect = GetDrawable(Resource.Drawable.button_correct); var backgroundError = GetDrawable(Resource.Drawable.button_error); var button = sender as Button; if (button != null) { if (button.Text == _currentItem.GetCorrectAnswer()) { _correctAnswersCount++; button.Background = backgroundCorrect; } else { button.Background = backgroundError; var correctButton = GetCorrectButton(); correctButton.Background = backgroundCorrect; } } await Execute(HandleTimer, 2000); }