NullReferenceException: Object reference not set to an instance of an object

Questions & Answers
1

When I click on the run button in the unity editor it gives out this error, but when I select gameobject SoundManager all works fine

I recorded a video to make it clear what I mean

NullReferenceException: Object reference not set to an instance of an object
SoundControll.Initial () (at Assets/Scripts/Sounds/SoundControll.cs:48)
SoundControll.Start () (at Assets/Scripts/Sounds/SoundControll.cs:18)

using System;
using UnityEngine;

public class SoundControll : MonoBehaviour
{
public Sound soundAudioClips;
[SerializeField] private AudioSources audioSource;

private void Awake()
{
    audioSource = new AudioSources[soundAudioClips.Length];
}

private void Start()
{
    Initial();
}

private void OnEnable()
{
    EventManager.OnSoundBySoundsControllEvent += OnSoundControllEventHandler;
}

public void PlaySound(Sounds sound)
{
    if (!GameManager.instance.Sound)
    {
        Stop();
        return;
    }

    var clip = Array.Find(audioSource, s => s.sound == sound);
    if (clip is null)
    {
        Debug.LogError($"Sound {sound} not found!");
        return;
    }

    clip?.source?.Play();
}

private void Initial()
{
    for (int i = 0; i < audioSource.Length; i++)
    {
        audioSource*.source = gameObject.AddComponent<AudioSource>();*

audioSource_.sound = soundAudioClips*.sound;
audioSource.source.clip = soundAudioClips.audioClip;
audioSource.source.volume = soundAudioClips.volume;
audioSource.source.loop = soundAudioClips.loop;
}
}
private void OnSoundControllEventHandler(Sounds sound)
{
PlaySound(sound);
}
private void Stop()
{
Array.ForEach(audioSource, s => s.source?.Stop());
}
private void OnDisable()
{
EventManager.OnSoundBySoundsControllEvent -= OnSoundControllEventHandler;
}
[System.Serializable]
public class AudioSources
{
public Sounds sound;
public AudioSource source;
}
}*_

2

You’ve got Unitys callstack wrong mate, therefore it will always return empty.
You are calling OnSoundControlEventHandler and playing a sound before you call the list.
The stack goes like this = Awake → OnEnable → Start.

Try giving the list what it needs before you start playing sounds. Put the eventhandler after Initial and you’ll see that it works.

3