Graphic.CrossFadeAlpha

Parameters

Description

对与此图形关联的 CanvasRenderer 颜色的 Alpha 执行 Tween 操作。

在附加了 CanvasRenderer 的 Graphic 上创建淡化特效。选择作为淡化目标的 Alpha 级别，然后选取淡化速度以便随时间推移看到平滑的淡化。UI Image 和 Text 是能够应用此特效的一些元素。

//Attach this script to a GameObject
//Create an Image GameObject by going to Create>UI>Image. Attach this Image to the Image field in your GameObject’s Inspector window.
//This script creates a toggle that fades an Image in and out.
using UnityEngine;
using UnityEngine.UI;

public class Example : MonoBehaviour
{
    //Attach an Image you want to fade in the GameObject's Inspector
    public Image m_Image;
    //Use this to tell if the toggle returns true or false
    bool m_Fading;

    void Update()
    {
        //If the toggle returns true, fade in the Image
        if (m_Fading == true)
        {
            //Fully fade in Image (1) with the duration of 2
            m_Image.CrossFadeAlpha(1, 2.0f, false);
        }
        //If the toggle is false, fade out to nothing (0) the Image with a duration of 2
        if (m_Fading == false)
        {
            m_Image.CrossFadeAlpha(0, 2.0f, false);
        }
    }

    void OnGUI()
    {
        //Fetch the Toggle's state
        m_Fading = GUI.Toggle(new Rect(0, 0, 100, 30), m_Fading, "Fade In/Out");
    }
}