Hello, in the Complete C# Unity Game Developer 2D course, on the Section 4 in the Script im developing the category where you can choose wich set of questions you want to answer, the problem is that i get this error in the console NullReferenceException: Object reference not set to an instance of an object. in the Script LeagueOfLegendsButton.
//QUIZ CLASS
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> questionsLol = new List<QuestionSO>();
[SerializeField] List<QuestionSO> questionsJava = new List<QuestionSO>();
QuestionSO currentQuestion;
[Header("Answers")]
[SerializeField] GameObject[] answerButtons;
int correctAnswerIndex;
bool hasAnweredEarly = true;
[Header("Button Colors")]
[SerializeField] Sprite defaultAnswerSprite;
[SerializeField] Sprite correctAnswerSprite;
[Header("Timer")]
[SerializeField] Image timerImage;
Timer timer;
[Header("Scoring")]
[SerializeField] TextMeshProUGUI scoreText;
ScoreKeeper scoreKeeper;
[Header("ProgressBar")]
[SerializeField] Slider progressBar;
public bool isComplete;
Image buttonImage;
public bool lolQuestions = true;
public bool javaQuestions = true;
void Awake()
{
//if(lolQuestions == false){
timer = FindObjectOfType<Timer>();
scoreKeeper = FindObjectOfType<ScoreKeeper>();
progressBar.maxValue = questionsLol.Count;
progressBar.value = 0;
/*}
else if (javaQuestions == false)
{
timer = FindObjectOfType<Timer>();
scoreKeeper = FindObjectOfType<ScoreKeeper>();
progressBar.maxValue = questionsJava.Count;
progressBar.value = 0;
}*/
}
void Update()
{
timerImage.fillAmount = timer.fillFraction;
if(timer.loadNextQuestion)
{
if(progressBar.value == progressBar.maxValue)
{
isComplete = true;
return;
}
hasAnweredEarly = false;
GetNextQuestion();
timer.loadNextQuestion = false;
}
else if(!hasAnweredEarly && !timer.isAnsweringQuestion)
{
DisplayAnswer(-1); // -1 viene usato per cadere direttamente nel else statement
SetButtonState(false);
}
}
public void OnAnswerSelected(int index)
{
hasAnweredEarly = true;
DisplayAnswer(index);
SetButtonState(false);
timer.CancelTimer();
scoreText.text = "Score: " + scoreKeeper.CalculateScore() + "%";
}
void DisplayAnswer(int index) // cambia il colore della risposta esatta modificando lo sprite dell'Image
{
if(index == currentQuestion.GetCorrectAnswerIndex())
{
questionText.text = "Correct!";
buttonImage = answerButtons[index].GetComponent<Image>();
buttonImage.sprite = correctAnswerSprite;
scoreKeeper.IncrementCorrectAnswers();
}
else
{
correctAnswerIndex = currentQuestion.GetCorrectAnswerIndex();
string correctAnswer = currentQuestion.GetAnswer(correctAnswerIndex);
questionText.text = "I'm sorry but the correct answer is\n" + correctAnswer;
buttonImage = answerButtons[correctAnswerIndex].GetComponent<Image>();
buttonImage.sprite = correctAnswerSprite;
}
}
void GetNextQuestion()
{
//if(lolQuestions == false){
if(questionsLol.Count > 0)
{
SetButtonState(true);
SetDefaultButtonSprites();
GetRandomQuestion();
DisplayQuestion();
progressBar.value++;
scoreKeeper.IncrementQuestionSeen();
}
/*}
else if(javaQuestions == false)
{
if(questionsLol.Count > 0)
{
SetButtonState(true);
SetDefaultButtonSprites();
GetRandomQuestion();
DisplayQuestion();
progressBar.value++;
scoreKeeper.IncrementQuestionSeen();
}
}*/
}
void GetRandomQuestion()
{
//if(lolQuestions == false){
int index = Random.Range(0, questionsLol.Count);
currentQuestion = questionsLol[index];
if(questionsLol.Contains(currentQuestion))
{
questionsLol.Remove(currentQuestion);
}
/*}
else if (javaQuestions == false)
{
int index = Random.Range(0, questionsJava.Count);
currentQuestion = questionsJava[index];
if(questionsJava.Contains(currentQuestion))
{
questionsJava.Remove(currentQuestion);
}
}*/
}
void DisplayQuestion()
{
questionText.text = currentQuestion.GetQuestion();
for(int i = 0; i <answerButtons.Length; i++){ // raggruppa tutte le risposte del component child Text del component padre QuizCanvas e inserisce la risposta
// in ogni testo recuperato
TextMeshProUGUI buttonText = answerButtons[i].GetComponentInChildren<TextMeshProUGUI>();
buttonText.text = currentQuestion.GetAnswer(i);
}
}
void SetButtonState(bool state)// disabilità il bottone dopo aver risposto alla domanda
{
for (int i = 0; i < answerButtons.Length; i++)
{
Button button = answerButtons[i].GetComponent<Button>();
button.interactable = state;
}
}
void SetDefaultButtonSprites() // cambia il colore delle risposte modificando lo sprite dell'Image
{
for (int i = 0; i < answerButtons.Length; i++)
{
buttonImage = answerButtons[i].GetComponent<Image>();
buttonImage.sprite = defaultAnswerSprite;
}
}
}
//LeagueOfLegendsButton CLASS
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class LeagueOfLegendsButton : MonoBehaviour
{
Quiz quiz;
SchermataPrincipaleScript schermataPrincipaleScript;
void Awake()
{
quiz = FindObjectOfType<Quiz>();
schermataPrincipaleScript = FindObjectOfType<SchermataPrincipaleScript>();
}
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
}
public void ChangeCanvasLol()
{
quiz.gameObject.SetActive(true);
schermataPrincipaleScript.gameObject.SetActive(false);
quiz.lolQuestions = false;
}
}
