1 using UnityEngine;
 2 using System.Collections;
 3 using UnityEngine.EventSystems;
 4 using UnityEngine.UI;
 5 
 6 /// <summary>
 7 /// 虚拟摇杆
 8 /// </summary>
 9 public class Rocker : Base, IBeginDragHandler,IDragHandler, IEndDragHandler
10 {
11     public RectTransform canvas;//画布RectTransform
12 
13     private RectTransform rockerBg;//摇杆背景RectTransform
14     private float ratio;//画布与屏幕之间的比例
15     private Vector2 parentCenter;//摇杆背景图中心点的屏幕坐标,即摇杆初始位置坐标。
16     private Touch touch;//代表控制摇杆的手指
17 
18     //摇杆移动方向的方向向量的X轴的值与Y轴的值
19     public static float x;
20     public static float y
21     private void Start()
22     {
23         rockerBg = this.transform.parent as RectTransform;
24         ratio = canvas.sizeDelta.x / Screen.width;
25         parentCenter = this.transform.parent.position;
26     }
27 
28     int a;
29     Vector2 dir;
30     /// <summary>
31     /// 当拖动摇杆时
32     /// </summary>
33     /// <param name="eventData"></param>
34     public void OnDrag(PointerEventData eventData)
35     {
36         foreach (var item in Input.touches)
37         {
38             if (item.fingerId == a)
39             {
40                 dir = item.position;
41                 break;
42             }
43         }
44         if (Vector3.Distance(dir, parentCenter) < rockerBg.sizeDelta.x / 2 / ratio)
45         {
46             this.pos = dir;
47         }
48         else
49         {
50             this.localPos = (dir - parentCenter).normalized * rockerBg.sizeDelta.x / 2f;
51         }
52         x = this.localPos.x / parentCenter.x;
53         y = this.localPos.y / parentCenter.y;
54     }
55 
56     /// <summary>
57     /// 当松开摇杆时
58     /// </summary>
59     /// <param name="eventData"></param>
60     public void OnEndDrag(PointerEventData eventData)
61     {
62         this.localPos = Vector3.zero;//让摇杆归位到初始位置
63         x = 0;
64         y = 0;
65     }
66 
67     /// <summary>
68     /// 当点击摇杆时
69     /// </summary>
70     /// <param name="eventData"></param>
71     public void OnBeginDrag(PointerEventData eventData)
72     {
73         touch = Input.touches[Input.touches.Length - 1];
74         a = touch.fingerId;
75     }
76 }