aibis-dream/Assets/Scripts/Framework/OtherKit/FadeKit.cs

using System.Collections;
using DG.Tweening;
using UnityEngine;
using UnityEngine.UI;

namespace AibisDream.Framework
{
    public static class FadeKit
    {
        public static IEnumerator FadeInAsync(this Image image, float duration, bool useUnscaledTime = false)
        {
            var tweener = StartFade(image, 1f, duration, useUnscaledTime);
            if (tweener != null)
            {
                yield return tweener.WaitForCompletion();
            }
        }

        public static void FadeIn(this Image image, float duration)
        {
            StartFade(image, 1f, duration, false);
        }

        public static IEnumerator FadeOutAsync(this Image image, float duration, bool useUnscaledTime = false)
        {
            var completed = false;
            var tweener = StartFade(image, 0f, duration, useUnscaledTime);
            if (tweener == null)
            {
                image?.gameObject.SetActive(false);
                yield break;
            }

            tweener.OnComplete(() => completed = true);
            yield return tweener.WaitForCompletion();
            if (completed && image != null)
            {
                image.gameObject.SetActive(false);
            }
        }

        public static void FadeOut(this Image image, float duration)
        {
            var tweener = StartFade(image, 0f, duration, false);
            if (tweener == null)
            {
                image?.gameObject.SetActive(false);
                return;
            }

            tweener.OnComplete(() =>
            {
                if (image != null)
                {
                    image.gameObject.SetActive(false);
                }
            });
        }

        private static Tweener StartFade(Image image, float targetAlpha, float duration, bool useUnscaledTime)
        {
            if (image == null)
            {
                return null;
            }

            image.DOKill(false);
            image.gameObject.SetActive(true);

            duration = Mathf.Max(0f, duration);
            if (duration <= 0f)
            {
                var color = image.color;
                color.a = targetAlpha;
                image.color = color;
                return null;
            }

            return image.DOFade(targetAlpha, duration).SetUpdate(useUnscaledTime);
        }
    }
}