NewSingleton

Important Attention Reminder

Coding Style wiki

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NewSingleton<T> is the plain C# class singleton base class of SingletonSystem (non-MonoBehaviour). It uses double-checked locking with lazy creation (new T()) to ensure the instance is created only once under multi-threading, suitable for data or logic manager classes that do not need to live on a GameObject.

Namespace	OxGKit.SingletonSystem
Type	public class NewSingleton<T> where T : class, new()
Source	NewSingleton.cs

using OxGKit.SingletonSystem;

Attention The generic constraint is where T : class, new() — type T must have a public parameterless constructor.

Reminder For manager classes that need the Unity lifecycle and scene objects, use MonoSingleton instead.

Quick Start

using OxGKit.SingletonSystem;

// Option 1: use by inheritance
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();

// Option 2: without inheritance, use directly as a generic holder
public class ScoreService
{
    public int score = 0;
}

NewSingleton<ScoreService>.GetInstance().score++;

Methods Overview

Method	Description
GetInstance	Gets the singleton instance (lazy creation).
InitInstance	Initializes the singleton instance (same as calling GetInstance).
CheckInstanceExists	Checks if an instance exists.
DestroyInstance	Destroys the singleton instance (only clears the static reference).

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GetInstance

public static T GetInstance()

Gets the singleton instance; if no instance exists yet, double-checked locking ensures it is created only once with new T() under race conditions.

var scoreManager = ScoreManager.GetInstance();

InitInstance

public static void InitInstance()

Initializes the singleton instance (same as calling GetInstance); suitable for explicitly controlling the creation order during boot (warm-up).

ScoreManager.InitInstance();

CheckInstanceExists

public static bool CheckInstanceExists()

Checks if an instance exists (does not trigger creation).

if (ScoreManager.CheckInstanceExists())
    ScoreManager.AddScore();

DestroyInstance

public static void DestroyInstance()

Destroys the singleton instance (only clears the static reference); if the old instance is still referenced elsewhere, that object is not released by this call — it is not a disposal mechanism.

ScoreManager.DestroyInstance();

Attention After clearing, the next GetInstance call creates a brand-new instance — the old instance's state is not preserved.