How can change UI text by mouse-click on an object in Unity3D?

Question

I have an object in Unity (cube) which its material changes with mouse click. I want to show information about each material in a UI text. So, the information needs to be changed. I have written the following script and it works when I assign it to a UI button. It means that my text is changed when I click on the button. But when I assign it to the cube, my text isn’t changed by mouse click. I would appreciate it if you could answer my question.

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


public class CubeText : MonoBehaviour
{
   public Text changingText;
   private int i = 0;

   public void textChange()
   {

       {

       switch (i)
       {
           case 0:
               changingText.text = "Parket...";
               break;
           case 1:
               changingText.text = "Kashi...!";
               break;
           case 2:
               changingText.text = "Seramic...!";
               break;
       }
       i++;
       i = i % 3;         
       }
   }
}