UICanvasGroup

UICanvasGroup.cs

using System;
using System.Collections;
using UnityEngine;
using UnityEngine.EventSystems;

namespace Game.UI
{
    [RequireComponent(typeof(CanvasGroup))]
    public abstract class UICanvasGroup : UIBehaviour
    {
        [SerializeField]
        protected CanvasGroup m_canvasGroup = default;

        /// <summary>
        /// Get the canvas group.
        /// </summary>
        public CanvasGroup CanvasGroup => m_canvasGroup;

        [SerializeField]
        protected float m_fadeDuration = default;

        protected Coroutine m_fadeCoroutine;

        /// <summary>
        /// Method called when the UI is show.
        /// </summary>
        public virtual void Show(Action onCompleted = null)
        {
            if (m_fadeCoroutine != null)
            {
                StopCoroutine(m_fadeCoroutine);
                m_fadeCoroutine = null;
            }
            m_fadeCoroutine = StartCoroutine(FadeIn(onCompleted));
        }

        /// <summary>
        /// Method called when the UI is hidden.
        /// </summary>
        public virtual void Hide(Action onCompleted = null)
        {
            if (m_fadeCoroutine != null)
            {
                StopCoroutine(m_fadeCoroutine);
                m_fadeCoroutine = null;
            }
            m_fadeCoroutine = StartCoroutine(FadeOut(onCompleted));
        }

        /// <summary>
        /// Initialize the UI.
        /// </summary>
        protected virtual void Initialize() { }

        /// <summary>
        /// Method called fade in the UI.
        /// </summary>
        /// <returns></returns>
        private IEnumerator FadeIn(Action onCompleted = null)
        {
            while (m_canvasGroup.alpha < 1f)
            {
                m_canvasGroup.alpha += Time.deltaTime / m_fadeDuration;
                yield return null;
            }
            onCompleted?.Invoke();
            yield return null;
        }

        /// <summary>
        /// Method called fade out the UI.
        /// </summary>
        /// <returns></returns>
        private IEnumerator FadeOut(Action onCompleted = null)
        {
            while (m_canvasGroup.alpha > 0f)
            {
                m_canvasGroup.alpha -= Time.deltaTime / m_fadeDuration;
                yield return null;
            }
            onCompleted?.Invoke();
            yield return null;
        }

#if UNITY_EDITOR
        protected override void OnValidate()
        {
            base.OnValidate();
            m_canvasGroup ??= GetComponent<CanvasGroup>();
        }

        protected override void Reset()
        {
            base.Reset();
            m_canvasGroup = GetComponent<CanvasGroup>();
        }
#endif
    }
}