You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
78 lines
2.8 KiB
78 lines
2.8 KiB
using UnityEngine; |
|
/// <summary> |
|
/// Be aware this will not prevent a non singleton constructor |
|
/// such as `T myT = new T();` |
|
/// To prevent that, add `protected T () {}` to your singleton class. |
|
/// |
|
/// As a note, this is made as MonoBehaviour because we need Coroutines. |
|
/// </summary> |
|
public class Singleton<T> : MonoBehaviour where T : MonoBehaviour |
|
{ |
|
private static T _instance; |
|
|
|
private static object _lock = new object(); |
|
|
|
public static T Instance |
|
{ |
|
get |
|
{ |
|
if (applicationIsQuitting) |
|
{ |
|
Debug.LogWarning("[Singleton] Instance '" + typeof(T) + |
|
"' already destroyed on application quit." + |
|
" Won't create again - returning null."); |
|
return null; |
|
} |
|
|
|
lock (_lock) |
|
{ |
|
if (_instance == null) |
|
{ |
|
_instance = (T)FindObjectOfType(typeof(T)); |
|
|
|
if (FindObjectsOfType(typeof(T)).Length > 1) |
|
{ |
|
Debug.LogError("[Singleton] Something went really wrong " + |
|
" - there should never be more than 1 singleton!" + |
|
" Reopenning the scene might fix it."); |
|
return _instance; |
|
} |
|
|
|
if (_instance == null) |
|
{ |
|
GameObject singleton = new GameObject(); |
|
_instance = singleton.AddComponent<T>(); |
|
singleton.name = "(singleton) " + typeof(T).ToString(); |
|
|
|
DontDestroyOnLoad(singleton); |
|
|
|
Debug.Log("[Singleton] An instance of " + typeof(T) + |
|
" is needed in the scene, so '" + singleton + |
|
"' was created with DontDestroyOnLoad."); |
|
} |
|
else |
|
{ |
|
Debug.Log("[Singleton] Using instance already created: " + |
|
_instance.gameObject.name); |
|
} |
|
} |
|
|
|
return _instance; |
|
} |
|
} |
|
} |
|
|
|
private static bool applicationIsQuitting = false; |
|
/// <summary> |
|
/// When Unity quits, it destroys objects in a random order. |
|
/// In principle, a Singleton is only destroyed when application quits. |
|
/// If any script calls Instance after it have been destroyed, |
|
/// it will create a buggy ghost object that will stay on the Editor scene |
|
/// even after stopping playing the Application. Really bad! |
|
/// So, this was made to be sure we're not creating that buggy ghost object. |
|
/// </summary> |
|
public void OnDestroy() |
|
{ |
|
applicationIsQuitting = true; |
|
} |
|
}
|
|
|