ButtonExtended

ButtonExtended.cs

// https://gist.github.com/nekomimi-daimao/7b29fbb6f5bda1bf71791412f35fa7ea

using System;
using UniRx;
using UnityEngine;
using UnityEngine.EventSystems;

namespace Nekomimi.Daimao
{
    [RequireComponent(typeof(CanvasGroup))]
    public class ButtonExtended : MonoBehaviour,
        IPointerDownHandler, IPointerUpHandler, IPointerEnterHandler, IPointerExitHandler, IDragHandler
    {
        private readonly BoolReactiveProperty _pointerIn = new(false);

        /// <summary>
        /// ポインターのイン/アウト.
        /// </summary>
        public IReadOnlyReactiveProperty<bool> PointerIn => _pointerIn;

        /// <summary>
        /// 有効/無効の切り替え.
        /// </summary>
        public readonly BoolReactiveProperty Interactable = new(true);

        private readonly Subject<float> _onClick = new();

        /// <summary>
        /// クリックイベント.
        /// 押されていた間の秒数も同時に通知される.
        /// </summary>
        public IObservable<float> OnClick => _onClick;

        private IDisposable _disposablePressed;
        private readonly FloatReactiveProperty _pressedSecond = new(0f);

        /// <summary>
        /// 押され続けている秒数.
        /// 押されている間は<see cref="Observable.EveryUpdate"/>の間隔で更新される.
        /// </summary>
        public IReadOnlyReactiveProperty<float> PressedSecond => _pressedSecond;

        #region IPointerCallbacks

        void IPointerDownHandler.OnPointerDown(PointerEventData eventData)
        {
            Release();

            if (!Interactable.Value)
            {
                return;
            }

            _disposablePressed = Observable.EveryUpdate()
                .Select(_ => Time.deltaTime)
                .TakeUntilDisable(this)
                .Subscribe(f => _pressedSecond.Value += f);
        }

        void IPointerUpHandler.OnPointerUp(PointerEventData eventData)
        {
            if (PointerIn.Value && Interactable.Value)
            {
                _onClick.OnNext(PressedSecond.Value);
            }

            Release();
        }

        void IPointerEnterHandler.OnPointerEnter(PointerEventData eventData)
        {
            _pointerIn.Value = true;
        }

        void IPointerExitHandler.OnPointerExit(PointerEventData eventData)
        {
            _pointerIn.Value = false;
            Release();
        }

        void IDragHandler.OnDrag(PointerEventData eventData)
        {
            // https://discussions.unity.com/t/mouse-drag-element-inside-scrollrect-throws-pointerup-event/150840/4
        }

        #endregion

        private void Release()
        {
            _disposablePressed?.Dispose();
            _disposablePressed = null;
            _pressedSecond.Value = 0f;
        }

        public virtual void OnStart()
        {
        }

        [SerializeField]
        public CanvasGroup canvasGroup;

        private readonly CompositeDisposable _compositeDisposable = new();

        private void Awake()
        {
            _compositeDisposable.Add(_pointerIn);
            _compositeDisposable.Add(Interactable);
            _compositeDisposable.Add(_onClick);
            _compositeDisposable.Add(_pressedSecond);

            _compositeDisposable.AddTo(this);

            if (canvasGroup == null)
            {
                canvasGroup = GetComponent<CanvasGroup>();
            }
        }

        private void Start()
        {
            OnStart();
        }

#if UNITY_EDITOR

        private void Reset()
        {
            if (canvasGroup == null)
            {
                canvasGroup = GetComponent<CanvasGroup>();
            }
        }

#endif
    }
}