UGUI Image显示倒计时

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

public class UIResume : MonoBehaviour
{
    public Image imgCount;  //Image
    public Sprite[] spCount;//Sprite
   
    public void StartCount()
    {
        Show();
        StartCoroutine(StartCountCor());//开始倒计时
    }

    IEnumerator StartCountCor()
    {
        int i = 3;
        while (i > 0)
        {
            imgCount.sprite = spCount[i - 1];
            i--;
            yield return new WaitForSeconds(1);//等待1秒
            if (i <= 0)
            {
                break;
            }
        }       
    }

   
}