SingletonManager

Description

The SingletonManager class implements a singleton pattern for game objects, ensuring that only one instance of a particular object type exists. It destroys any previous instances when a new one is created, making it useful for manager objects, controllers, and other components that should be unique in the game world.

Namespace

Universe.Helper

Properties

Property Type Description
singletonId string Unique identifier for this singleton type

Methods

OnInit 

void OnInit()

Called when the script initializes. Checks if an instance with the same singletonId already exists, destroys it if found, and registers this object as the new instance.

Example Usage 

// Create a singleton game manager
SingletonManager gameManagerSingleton = new SingletonManager();
gameManagerSingleton.singletonId = "GameManager";

// Create a singleton audio controller
SingletonManager audioControllerSingleton = new SingletonManager();
audioControllerSingleton.singletonId = "AudioController";

// Create a singleton player data controller that persists between scenes
SingletonManager playerDataSingleton = new SingletonManager();
playerDataSingleton.singletonId = "PlayerData";

// Get a reference to a singleton from another script
UniObject GetAudioController() {
    return StorageUtil.GetTempData("AudioController", null);
}

Technical Details

  • The singleton pattern is implemented using StorageUtil.GetTempData() and StorageUtil.SetTempData()
  • When initialized, the manager checks if an object with the same singletonId already exists
  • If a previous instance exists, it is destroyed to maintain the singleton pattern
  • The current object is then registered as the singleton instance for that ID
  • Other scripts can access the singleton through StorageUtil.GetTempData(singletonId, null)

Use Cases

  • Game managers that coordinate game state
  • Audio controllers that manage sound playback
  • Input managers that process player input
  • UI controllers that manage user interface elements
  • Resource managers that handle asset loading
  • Network managers for multiplayer games
  • Persistent data controllers that maintain state between scenes

Notes

  • Each singleton type should have a unique singletonId
  • Consider using descriptive IDs like “GameManager”, “AudioController”, etc.
  • Singletons can create tight coupling between systems, so use judiciously
  • This implementation does not prevent creation of multiple singletons, but ensures only one exists at a time
  • For true enforcement of the singleton pattern, additional code would be needed
  • Singletons stored with this method will not persist between game sessions
  • Often used with manager and controller scripts that need to be globally accessible

Dependencies

  • Uses StorageUtil for temporary data storage
  • Uses UniObjectUtil.GetUniObject() to get a reference to the object
  • Uses UniObjectUtil.Destroy() to remove old instances