UI Image doesn't react to OnMouseDown()

Questions & Answers
1

When I use a 2D sprite the script works, when I use it on the UI Image it doesn’t. Does anyone know why?

I think it is because the polygon collider 2d doesnt reconize the UI image, and it reconizes the sprite. Don’t know why even though it’s the same image.

And the reason why I use the canvas and UI Images its because I’m making a 2d android app.

Do you guys know a solution?

2

You can Add EventTrigger Component to the Image and link it to OnMouseDown() method in the inspector with PointDown Event.
Also don’t forget to add EventSystem object in hierarchy.
@Sharckan

3

Hey everyone i know it’s been a while but i am asking a question. The event trigger will not work for me because I am making a game where you can control two player and i don’t think the event trigger can switch to another gameobject when Im hitting for exemple “Left Ctrl”. So is there anyway i can do this ? I made a script before but the OnMouseDown doesn’t work on a UI object, sooo, help me please ^^
Here is my script :

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ArrowLeft : MonoBehaviour
{
    [SerializeField] GameObject[] PlayerT;
    public GameObject PlayerG;
    public float speed = 6f;
    Rigidbody2D rb;
    bool Player1Playing = true;

    public void Start()
    {
        PlayerG = PlayerT[1];
    }

    public void Update()
    {
        if (Player1Playing == true)
        {
            PlayerG = PlayerT[0];
        }
        else if (Player1Playing == false)
        {
            PlayerG = PlayerT[1];
        }

    if (Input.GetKeyDown(KeyCode.LeftControl))
    {
        Player1Playing = !Player1Playing;
    }

       //This was a test/ if (Input.GetKey(KeyCode.T))
        {
            // This was a test/ PlayerG.transform.Translate(Vector2.left * speed * Time.deltaTime);
        }
    }

    public void OnPointerDown()
    {
        PlayerG.transform.Translate(Vector2.left * speed * Time.deltaTime);
    }

}
4

I was facing the same issue. You need to implement interface,IPointerDownHandler.

StackOverflow - How to detect click/touch events on UI and GameObjects