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How do you use a Singleton?

A Singleton is a design pattern that ensures there is only one instance of a particular class within a program.

The Singleton pattern provides a single global instance of a class, making it easily accessible from other scripts that need it, such as managing logic, audio, UI, and centralized resources within the world.

In ZEPETOScript, you can implement a Singleton in the following way:

private static _instance: ClassName = null;

public static get Instance(): ClassName {
	if (this._instance == null) {
		this._instance = GameObject.FindObjectOfType<ClassName>();
	return this._instance;



  • If there is already a GameObject with a Singleton script attached in the Scene, you can use this format.
  • If there isn't one, add code to create the GameObject.
    • Example: new GameObject("ObjectName").AddComponent<ClassName>();

Let's implement a Singleton for managing UI in an example:

  1. Add UI > Text and Button to the Scene.
  • Set up the logic to increase the score when the "IncreaseScore" button is pressed
  • Set up the logic to decrease the score when the "DecreaseScore" button is pressed

  1. Create a script called "ScoreManager," where the Singleton will be applied.
  • The ScoreManager script will be responsible for increasing/decreasing the score and updating the Text when called from other scripts.
import { ZepetoScriptBehaviour } from 'ZEPETO.Script';
import { GameObject } from 'UnityEngine';
import { Text } from 'UnityEngine.UI';
export default class ScoreManager extends ZepetoScriptBehaviour {
    // Singleton declaration
    private static _instance: ScoreManager = null;
    public static get Instance(): ScoreManager {
        if (this._instance == null) {
            this._instance = GameObject.FindObjectOfType<ScoreManager>();
        return this._instance;
    // Variable declaration
    public scoreText: Text;
    private _currentScore : number;
    Start() {   
        // Set initial score to 0 for testing
        this._currentScore = 0;
    // Other scripts can call IncreaseScore
    public IncreaseScore(amount: number) {
        this._currentScore += amount;
        this.scoreText.text = `Score : ${this._currentScore}`;
    // Other scripts can call DecreaseScore
    public DecreaseScore(amount: number) {
        this._currentScore -= amount;
        this.scoreText.text = `Score : ${this._currentScore}`;

  • Script Description
    • private static _instance: This is a private static variable within the class, initially set to null.
    • public static get Instance: This static property provides a way for external code to access the unique instance of this class.
    • Check if (this.\_instance == null). If it’s null, use GameObject.FindObjectOfType<>() to find and return a component of type ClassName, and assign it to the static variable.

  1. After writing the script, return to the Inspector and connect the Text component.

  1. Next, create a script called "ScoreLogicSample" to demonstrate how to call the Singleton. Ensure that ScoreManager and ScoreLogicSample are in the same directory.
  • Write code like this:
import { ZepetoScriptBehaviour } from 'ZEPETO.Script';
import { GameObject } from 'UnityEngine';
import { Text, Button } from 'UnityEngine.UI';
// Import Singleton script
import ScoreManager from './ScoreManager';
export default class ScoreLogicSample extends ZepetoScriptBehaviour {
    public increaseScoreButton: Button;
    public decreaseScoreButton: Button;
    // Declare variable of type ScoreManager
    private ScoreManager : ScoreManager;
    Start() {   
        // Assign ScoreManager to the variable
        this.ScoreManager = GameObject.FindObjectOfType<ScoreManager>();
        this.increaseScoreButton.onClick.AddListener(()=> {
            // Call the function declared in Singleton
        this.decreaseScoreButton.onClick.AddListener(()=> {
            // Call the function declared in Singleton

  • It's important to specify the path correctly when getting the Singleton script.
  • You can adapt the part where ScoreManager is called in your own script as needed.

  1. Press the [▶︎(play)] button to test.
  • You should observe the functions in ScoreManager being called when you click the buttons in ScoreLogicSample, making it work as expected.