负责处理音效相关事务

 public class AudioMgr : BaseManager<AudioMgr> {

    
     private AudioSource bkMusic = null;
    
     private float bkVolumn  = 1f;
    
  
    
     // 一个 soundObj 挂载了很多的AudioSource，要用的就添加，不用就删除
    
     private GameObject soundObj = null;
    
     private List<AudioSource> soundList = new List<AudioSource>();
    
     private float soundVolume = 1f;
    
  
    
     public AudioMgr() {
    
     MonoMgr.GetInstance().AddUpdateListener(Update);
    
     }
    
  
    
     private void Update() {
    
     for(int i = soundList.Count - 1; i >= 0; --i) {
    
         if (!soundLi