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Module Intro

Important Attention Reminder

Coding Style wiki​

Basic Instructions​

Singleton pattern module that supports two singleton base classes, MonoSingleton (MonoBehaviour) and NewSingleton (class), providing thread-safe lazy creation, find-or-create instance resolution in the scene, DontDestroyOnLoad cross-scene persistence control, and the OnCreate / OnStart / OnRelease lifecycle hooks.

  • Version: v1.0.2 (com.michaelo.oxgkit.singletonsystem)
  • Namespace: OxGKit.SingletonSystem

Reminder This module has no third-party dependencies and can be installed standalone.

Application Description​

Two Singleton Base Classes​

Base ClassDescription
MonoSingleton<T>MonoBehaviour singleton base class. When accessing the instance, it first looks for an existing instance in the scene, otherwise automatically creates a GameObject with the component attached; supports DontDestroyOnLoad persistence control and provides the OnCreate / OnStart / OnRelease lifecycle hooks.
NewSingleton<T>Plain C# class singleton base class (non-MonoBehaviour), lazily creating the instance with new T() (double-checked locking).

Lifecycle Hooks (MonoSingleton)​

MonoSingleton<T> implements Unity's Awake(), Start(), and OnDestroy() as private methods of the base class; implement your logic through the following hooks instead:

HookInvoked By
OnCreate()Unity Awake
OnStart()Unity Start
OnRelease()Unity OnDestroy

Important Do not implement Awake(), Start(), or OnDestroy() (occupied by the base class); every other Unity method (Update, OnEnable, etc.) can be implemented normally.

DontDestroyOnLoad Control​

  • Scene-placed instance: registers itself as the singleton in Awake, and the dontDestroyOnLoad field on the Inspector (default true) decides whether it persists across scenes.
  • Created from code: decided by the parameter of the first GetInstance(dontDestroyOnLoad) / InitInstance(dontDestroyOnLoad) call (default true).

Attention dontDestroyOnLoad takes effect on the first instance creation — decide it at the first access call site and keep it consistent.

Script Template Creation​

Quickly create a MonoSingleton template script via Right-Click Create/OxGKit/SingletonSystem/Template Mono Singleton.cs.

Simple Usage​

Implement a MonoSingleton​

using OxGKit.SingletonSystem;

public class GameManager : MonoSingleton<GameManager>
{
    // |-------------------------------------------------------------------------------------|
    // | Note: Except Awake(), Start() and OnDestroy(), other Unity methods can be override. |
    // |-------------------------------------------------------------------------------------|

    protected override void OnCreate()
    {
        /**
         * Do Somethings OnCreate In Here (Call by Unity.Awake)
         */
    }

    protected override void OnStart()
    {
        /**
         * Do Somethings OnStart In Here (Call by Unity.Start)
         */
    }

    protected override void OnRelease()
    {
        /**
         * Do Somethings OnRelease In Here (Call by Unity.OnDestroy)
         */
    }
}
// Get the instance (find-or-create, DontDestroyOnLoad by default)
GameManager.GetInstance();

// Scene-scoped singleton (destroyed with the scene, set once at the first access)
GameManager.GetInstance(dontDestroyOnLoad: false);

// Explicit initialization at boot (warm-up)
GameManager.InitInstance();

// Check if an instance exists
if (GameManager.CheckInstanceExists()) { /* ... */ }

// Destroy the instance (GameObject included)
GameManager.DestroyInstance();

Implement a NewSingleton​

using OxGKit.SingletonSystem;

public class ScoreManager : NewSingleton<ScoreManager>
{
    public int score = 0;

    public static void AddScore()
    {
        GetInstance().score++;
    }
}
// Get the instance (lazy new T() creation)
var scoreManager = ScoreManager.GetInstance();
ScoreManager.AddScore();

// Destroy the instance (only clears the static reference)
ScoreManager.DestroyInstance();

[Refer to Example]

Installation​

Install via git URL
Add https://github.com/michael811125/OxGKit.git?path=Assets/OxGKit/SingletonSystem/Scripts to Package Manager

Third-Party Libraries

  • None (this module has no third-party dependencies).

Samples (Package Manager -> Samples)

Module API​