Button.onClick

Description

UnityEvent that is triggered when the Button is pressed.

Use UnityEvent.AddListener to extend the onClick click events. The added UnityAction is called when the Button press is released. A Button can have multiple listeners. As an example, in the script example below, btn3 can have TaskOnClick added as a second listener call.

Note that EventType.MouseDown and EventType.MouseUp are called prior to onClick.

// To use this example, attach this script to an empty GameObject.
// Create three buttons (Create>UI>Button). Next, select your
// empty GameObject in the Hierarchy and click and drag each of your
// Buttons from the Hierarchy to the Your First Button, Your Second Button
// and Your Third Button fields in the Inspector.
// Click each Button in Play Mode to output their message to the console.
// Note that click means press down and then release.

using UnityEngine;
using UnityEngine.UI;

public class Example : MonoBehaviour
{
    //Make sure to attach these Buttons in the Inspector
    public Button m_YourFirstButton, m_YourSecondButton, m_YourThirdButton;

    void Start()
    {
        //Calls the TaskOnClick/TaskWithParameters/ButtonClicked method when you click the Button
        m_YourFirstButton.onClick.AddListener(TaskOnClick);
        m_YourSecondButton.onClick.AddListener(delegate {TaskWithParameters("Hello"); });
        m_YourThirdButton.onClick.AddListener(() => ButtonClicked(42));
        m_YourThirdButton.onClick.AddListener(TaskOnClick);
    }

    void TaskOnClick()
    {
        //Output this to console when Button1 or Button3 is clicked
        Debug.Log("You have clicked the button!");
    }

    void TaskWithParameters(string message)
    {
        //Output this to console when the Button2 is clicked
        Debug.Log(message);
    }

    void ButtonClicked(int buttonNo)
    {
        //Output this to console when the Button3 is clicked
        Debug.Log("Button clicked = " + buttonNo);
    }
}