I really need help here. I can’t figure out how to fix this issue I have:
NullReferenceException: Object reference not set to an instance of an object
Quiz.DisplayAnswer (System.Int32 index) (at Assets/Scripts/Quiz.cs:63)
Quiz.Update () (at Assets/Scripts/Quiz.cs:46)
here is my code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using TMPro;
using UnityEngine.UI;
public class Quiz : MonoBehaviour
{
[Header("Questions")]
[SerializeField] TextMeshProUGUI questionText;
[SerializeField] List<QuestionSO> questions = new List<QuestionSO>();
QuestionSO currentQuestion;
[Header("Answers")]
[SerializeField] GameObject[] answerButtons;
int correctAnswerIndex;
bool hasAnsweredEarly;
[Header("Button Colors")]
[SerializeField] Sprite defaultAnswerSprite;
[SerializeField] Sprite correctAnswerSprite;
[Header("Timer")]
[SerializeField] Image timerImage;
Timer timer;
void Start()
{
timer = FindObjectOfType<Timer>();
}
void Update()
{
timerImage.fillAmount = timer.fillFraction;
if(timer.loadNextQuestion)
{
hasAnsweredEarly = false;
GetNextQuestion();
timer.loadNextQuestion = false;
}
else if (!hasAnsweredEarly && !timer.isAnsweringQuestion)
{
DisplayAnswer(-1);
SetButtonState(false);
}
}
public void OnAnswerSelected(int index)
{
hasAnsweredEarly = true;
DisplayAnswer(index);
SetButtonState(false);
timer.CancelTimer();
}
void DisplayAnswer(int index)
{
Image buttonImage;
if(index == currentQuestion.GetCorrectAnswerIndex())
{
questionText.text = "Correct!";
buttonImage = answerButtons[index].GetComponent<Image>();
buttonImage.sprite = correctAnswerSprite;
}
else
{
correctAnswerIndex = currentQuestion.GetCorrectAnswerIndex();
string correctAnswer = currentQuestion.GetAnswer(correctAnswerIndex);
questionText.text = "Sorry, the correct answer was\n" + correctAnswer;
buttonImage = answerButtons[correctAnswerIndex].GetComponent<Image>();
buttonImage.sprite = correctAnswerSprite;
}
}
void GetNextQuestion()
{
if(questions.Count > 0)
{
SetButtonState(true);
SetDefaultButtonSprites();
GetRandomQuestion();
DisplayQuestion();
}
}
void GetRandomQuestion()
{
int index = Random.Range(0, questions.Count);
currentQuestion = questions[index];
if(questions.Contains(currentQuestion))
{
questions.Remove(currentQuestion);
}
}
void DisplayQuestion()
{
questionText.text = currentQuestion.GetQuestion();
for (int i = 0; i < answerButtons.Length; i++)
{
TextMeshProUGUI buttonText = answerButtons[i].GetComponentInChildren<TextMeshProUGUI>();
buttonText.text = currentQuestion.GetAnswer(i);
}
}
void SetButtonState(bool state)
{
for (int i = 0; i < answerButtons.Length; i++)
{
Button button = answerButtons[i].GetComponent<Button>();
button.interactable = state;
}
}
void SetDefaultButtonSprites()
{
for(int i = 0; i < answerButtons.Length; i++)
{
Image buttonImage = answerButtons[i].GetComponent<Image>();
buttonImage.sprite = (defaultAnswerSprite);
}
}
}
really appreciate the help!
