void OnDestroy()
 {
     // Only set sInstance to null if the actual instance is destroyed.
     if (sInstance == this)
     {
         sInstance = null;
     }
 }
 private void Awake()
 {
     if (sInstance == null)
     {
         sInstance = this;
     }
     else if (sInstance != this)
     {
         Destroy(this.gameObject);
         return;
     }
 }