private void ChoiceButton_OnClick(Button button, Choice choice) { if (choice.IsCorrect) { stopwatch.Start(); // Add the answer if it was the first one picked. if (!isAnswered) { points.FillColor = Color.Green; stats.AddAnswer(choice); } // Disable all other buttons. foreach (var b in choicesContainer.GetChildren() .Where(entity => entity is Button btn && btn != button)) { b.Disabled = true; } } else { button.Disabled = true; // Add the answer if it was the first one picked. if (!isAnswered) { points.FillColor = Color.Red; stats.AddAnswer(choice); } } isAnswered = true; }