ProjectDDD/Assets/_DDD/_Scripts/GameUi/FadeUi.cs

using System.Threading.Tasks;
using DG.Tweening;
using UnityEngine;

namespace DDD
{
    public class FadeUi : BaseUi, IEventHandler<FadeInEvent>, IEventHandler<FadeOutEvent>
    {
        protected override void Awake()
        {
            base.Awake();
            
            _canvasGroup.alpha = 0f;
        }

        protected override void TryRegister()
        {
            EventBus.Register<FadeInEvent>(this);
            EventBus.Register<FadeOutEvent>(this);
        }

        protected override void TryUnregister()
        {
            EventBus.Unregister<FadeInEvent>(this);
            EventBus.Unregister<FadeOutEvent>(this);
        }

        public void Invoke(FadeInEvent evt)
        {
            _ = FadeInAsync(evt);
        }

        public void Invoke(FadeOutEvent evt)
        {
            _ = FadeOutAsync(evt);
        }

        private async Task FadeInAsync(FadeInEvent evt)
        {
            await _canvasGroup.DOFade(0f, evt.Duration)
                .SetUpdate(true)
                .AsyncWaitForCompletion();
            
            ClosePanel();
            
            evt.CompletionSource.SetResult(true);
        }

        private async Task FadeOutAsync(FadeOutEvent evt)
        {
            OpenPanel();

            await _canvasGroup.DOFade(1f, evt.Duration)
                .SetUpdate(true)
                .AsyncWaitForCompletion();
            
            evt.CompletionSource.SetResult(true);
        }
    }
}