SamsonGame/Assets/Sources/Lean/GUI/Scripts/LeanSwipe.cs

using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.Events;
using Lean.Transition;
using Lean.Common;

namespace Lean.Gui
{
	/// <summary>This component allows you to detect when a finger swipes over the current RectTransform.</summary>
	[RequireComponent(typeof(RectTransform))]
	[HelpURL(LeanGui.HelpUrlPrefix + "LeanSwipe")]
	[AddComponentMenu(LeanGui.ComponentMenuPrefix + "Swipe")]
	public class LeanSwipe : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
	{
		/// <summary>The swiping finger must move at least this many pixels.</summary>
		public float MinimumDistance { set { minimumDistance = value; } get { return minimumDistance; } } [SerializeField] private float minimumDistance = 100.0f;

		/// <summary>The swiping finger must move MinimumDistance within this amount of seconds.</summary>
		public float MaximumTime { set { maximumTime = value; } get { return maximumTime; } } [SerializeField] private float maximumTime = 0.125f;

		/// <summary>If you need the swipe to be in a specific direction, then enable this.</summary>
		public bool CheckAngle { set { checkAngle = value; } get { return checkAngle; } } [SerializeField] private bool checkAngle;

		/// <summary>0 = up
		/// 90 = right
		/// 180 = down
		/// 270 = left</summary>
		public float DesiredAngle { set { desiredAngle = value; } get { return desiredAngle; } } [SerializeField] private float desiredAngle;

		/// <summary>360 = full circle
		/// 180 = half circle
		/// 90 = quarter circle</summary>
		public float MaximumRange { set { maximumRange = value; } get { return maximumRange; } } [Range(0.0f, 360.0f)] [SerializeField] private float maximumRange = 90.0f;

		/// <summary>This allows you to perform a transition when you swipe this UI element.
		/// You can create a new transition GameObject by right clicking the transition name, and selecting <b>Create</b>.
		/// For example, the <b>LeanPlaySound (Play Sound Transition)</b> component can be used to play a click sound.</summary>
		public LeanPlayer SwipeTransitions { get { if (swipeTransitions == null) swipeTransitions = new LeanPlayer(); return swipeTransitions; } } [SerializeField] private LeanPlayer swipeTransitions;

		/// <summary>This allows you to perform an action when you swipe this UI element.</summary>
		public UnityEvent OnSwipe { get { if (onSwipe == null) onSwipe = new UnityEvent(); return onSwipe; } } [SerializeField] private UnityEvent onSwipe;

		[System.NonSerialized]
		protected bool dragging;

		[System.NonSerialized]
		protected float dragTime;

		[System.NonSerialized]
		protected Vector2 dragDelta;

		[System.NonSerialized]
		private RectTransform cachedRectTransform;

		[System.NonSerialized]
		private bool cachedRectTransformSet;

		public RectTransform CachedRectTransform
		{
			get
			{
				if (cachedRectTransformSet == false)
				{
					cachedRectTransform    = GetComponent<RectTransform>();
					cachedRectTransformSet = true;
				}

				return cachedRectTransform;
			}
		}

		public void OnBeginDrag(PointerEventData eventData)
		{
			var vector = default(Vector2);

			// Is this pointer inside this rect transform?
			if (RectTransformUtility.ScreenPointToLocalPointInRectangle(CachedRectTransform, eventData.position, eventData.pressEventCamera, out vector) == true)
			{
				dragging  = true;
				dragTime  = 0.0f;
				dragDelta = Vector2.zero;
			}
		}

		public virtual void OnDrag(PointerEventData eventData)
		{
			if (dragging == true)
			{
				dragDelta += eventData.delta;
			}
		}

		public void OnEndDrag(PointerEventData eventData)
		{
			dragging = false;
		}

		protected virtual void Update()
		{
			if (dragging == true)
			{
				dragTime += Time.deltaTime;

				if (dragTime <= maximumTime && dragDelta.magnitude >= minimumDistance)
				{
					// If this swipe angle is incorrect, return
					if (checkAngle == true)
					{
						var angle = Mathf.Atan2(dragDelta.x, dragDelta.y) * Mathf.Rad2Deg;
						var delta = Mathf.DeltaAngle(angle, desiredAngle) * 2.0f;

						if (delta <= -maximumRange || delta > maximumRange)
						{
							return;
						}
					}

					// Cancel drag and invoke
					dragging = false;

					if (swipeTransitions != null)
					{
						swipeTransitions.Begin();
					}

					if (onSwipe != null)
					{
						onSwipe.Invoke();
					}
				}
			}
		}
	}
}

#if UNITY_EDITOR
namespace Lean.Gui.Editor
{
	using TARGET = LeanSwipe;

	[UnityEditor.CanEditMultipleObjects]
	[UnityEditor.CustomEditor(typeof(TARGET))]
	public class LeanSwipe_Editor : LeanEditor
	{
		protected override void OnInspector()
		{
			TARGET tgt; TARGET[] tgts; GetTargets(out tgt, out tgts);

			BeginError(Any(tgts, t => t.MinimumDistance <= 0.0f));
				Draw("minimumDistance", "The swiping finger must move at least this many pixels.");
			EndError();
			BeginError(Any(tgts, t => t.MaximumTime <= 0.0f));
				Draw("maximumTime", "The swiping finger must move MinimumDistance within this amount of seconds.");
			EndError();
			Draw("checkAngle", "If you need the swipe to be in a specific direction, then enable this.");
			if (Any(tgts, t => t.CheckAngle == true))
			{
				BeginIndent();
					Draw("desiredAngle", "0 = up\n\n90 = right\n\n180 = down\n\n270 = left");
					BeginError(Any(tgts, t => t.MaximumRange <= 0.0f && t.MaximumRange >= 360.0f));
						Draw("maximumRange", "360 = full circle\n\n180 = half circle\n\n 90 = quarter circle");
					EndError();
				EndIndent();
			}

			Separator();

			Draw("swipeTransitions", "This allows you to perform a transition when you swipe this UI element. You can create a new transition GameObject by right clicking the transition name, and selecting Create. For example, the LeanPlaySound (Play Sound Transition) component can be used to play a click sound.");

			Separator();

			Draw("onSwipe");
		}
	}
}
#endif