Version: 2021.3
LanguageEnglish
  • C#

UnityEvent.AddListener

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Declaration

public void AddListener(Events.UnityAction call);

Parameters

call Callback function.

Description

Add a non persistent listener to the UnityEvent.

Use this to add a runtime callback. Adding multiple identical listeners results in only a single call being made.

//Attach this script to a GameObject
//This script creates a UnityEvent that calls a method when a key is pressed
//Note that 'q' exits this application.
using UnityEngine;
using UnityEngine.Events;

public class Example : MonoBehaviour { UnityEvent m_MyEvent = new UnityEvent();

void Start() { //Add a listener to the new Event. Calls MyAction method when invoked m_MyEvent.AddListener(MyAction); }

void Update() { // Press Q to close the Listener if (Input.GetKeyDown("q") && m_MyEvent != null) { Debug.Log("Quitting"); m_MyEvent.RemoveListener(MyAction);

#if UNITY_EDITOR UnityEditor.EditorApplication.isPlaying = false; #endif

Application.Quit(); }

//Press any other key to begin the action if the Event exists if (Input.anyKeyDown && m_MyEvent != null) { //Begin the action m_MyEvent.Invoke(); } }

void MyAction() { //Output message to the console Debug.Log("Do Stuff"); } }

Additional resources: UnityEventTools.AddPersistentListener.