arfoundation-samples/Assets/Scripts/UX/Tooltip.cs

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

public class Tooltip : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler
{
    [SerializeField]
    GameObject m_Tooltip;
    public GameObject toolTip
    {
        get { return m_Tooltip; }
        set { m_Tooltip = value; }
    }
    bool m_EnteredButton;
    Vector3 m_ToolTipOffset;

    void Start()
    {
        m_ToolTipOffset = new Vector3(-50,100,0);
    }

    void Update()
    {
        if(m_EnteredButton)
        {
              m_Tooltip.transform.position = Input.mousePosition + m_ToolTipOffset;
        }
    }


    public void OnPointerEnter(PointerEventData eventData)
    {
        m_EnteredButton = true;
        if(!gameObject.GetComponent<Button>().interactable)
        {
             m_Tooltip.SetActive(true);
        }
    }


    public void OnPointerExit(PointerEventData eventData)
    {
        m_EnteredButton = false;
        m_Tooltip.SetActive(false);
    }
}