Unity中实现UI的闪烁特效

最终效果如下：

---

一：判断Alpha

当Alpha值到达0或者1时，立即切换状态

using UnityEngine;
using UnityEngine.UI;

public class Blink : MonoBehaviour
{
    public float blinkSpeed;//闪烁速度
    private bool isAddAlpha;//是否增加透明度

    private Image img;//指向自身图片

    private void Start()
    {
        img = GetComponent<Image>();
    }

    private void Update()
    {
        if (isAddAlpha)
        {
            img.color += new Color(0, 0, 0, Time.deltaTime * blinkSpeed);
            if (img.color.a >= 1)
            {
                img.color = new Color(img.color.r, img.color.g, img.color.b, 1);
                isAddAlpha = false;
            }
        }
        else
        {
            img.color -= new Color(0, 0, 0, Time.deltaTime * blinkSpeed);
            if (img.color.a <= 0)
            {
                img.color = new Color(img.color.r, img.color.g, img.color.b, 0);
                isAddAlpha = true;
            }
        }
    }
}

---

二：判断Timer

当Alpha值到达0或1时，不立即切换状态，而是通过计时器判断

using UnityEngine;
using UnityEngine.UI;

public class Blink : MonoBehaviour
{
    public float blinkSpeed = 5;//闪烁速度

    private float timer;//计时器
    public float timeval = 1;//时间间隔

    private Image img;//指向自身图片

    private void Start()
    {
        img = GetComponent<Image>();
    }

    private void Update()
    {
        timer += Time.deltaTime;
        if (isAddAlpha)
        {
            img.color += new Color(0, 0, 0, Time.deltaTime * blinkSpeed);
            if (timer >= timeval)
            {
                img.color = new Color(img.color.r, img.color.g, img.color.b, 1);
                isAddAlpha = false;
                timer = 0;
            }
        }
        else
        {
            img.color -= new Color(0, 0, 0, Time.deltaTime * blinkSpeed);
            if (timer >= timeval)
            {
                img.color = new Color(img.color.r, img.color.g, img.color.b, 0);
                isAddAlpha = true;
                timer = 0;
            }
        }
    }
}