TianJin_23/Assets/DragBase.cs

using UnityEngine;
using UnityEngine.EventSystems;
using System.Collections;
using System;
using UnityEngine.UI;
using AX.MessageSystem;
//给空间添加监听事件要实现的一些接口
public class DragBase : MonoBehaviour, IPointerDownHandler, IDragHandler, IPointerUpHandler,
    IEndDragHandler
{

    private RectTransform canvas;          //得到canvas的ugui坐标
    private RectTransform imgRect;        //得到图片的ugui坐标
    Vector2 offset = new Vector3();    //用来得到鼠标和图片的差值
    Vector3 imgReduceScale = new Vector3(0.8f, 0.8f, 1);   //设置图片缩放
    Vector3 imgNormalScale = new Vector3(1, 1, 1);   //正常大小
    private GameObject TemporaryFather;
    private GameObject Fahter;

    Vector2 PosVector;
    // Use this for initialization
    void Start()
    {
        imgRect = GetComponent<RectTransform>();
        canvas = GameObject.Find("Canvas").GetComponent<RectTransform>();
      
    }    

    //当鼠标按下时调用 接口对应  IPointerDownHandler
    public void OnPointerDown(PointerEventData eventData)
    {
        pos = transform.GetComponent<RectTransform>().localPosition;
        Vector2 mouse;
        RectTransformUtility.ScreenPointToLocalPointInRectangle(this.transform.parent as RectTransform, Input.mousePosition, canvas.GetComponent<Canvas>().worldCamera, out mouse);
        vec2 = mouse;

    }
    Vector2 pos, vec2;
    //当鼠标拖动时调用   对应接口 IDragHandler
    public void OnDrag(PointerEventData eventData)
    {
       
        Vector2 mouseDrag = eventData.position;   //当鼠标拖动时的屏幕坐标
        Vector2 uguiPos = new Vector2();   //用来接收转换后的拖动坐标
        ////和上面类似
        bool isRect = RectTransformUtility.ScreenPointToLocalPointInRectangle(canvas, mouseDrag, eventData.enterEventCamera, out uguiPos);
       
       
        Vector2 mouse;
        RectTransformUtility.ScreenPointToLocalPointInRectangle(this.transform.parent as RectTransform, Input.mousePosition,
            canvas.GetComponent<Canvas>().worldCamera, out mouse);
        Vector2 off = mouse - vec2;
        vec2 = mouse;
        pos = pos + off;
        transform.GetComponent<RectTransform>().localPosition = pos;
       
    }
  
    //当鼠标抬起时调用  对应接口  IPointerUpHandler
    public void OnPointerUp(PointerEventData eventData)
    {
        offset = Vector2.zero;
        //if (!this.name.Contains("TwoArrows"))
        //{
        //    this.gameObject.transform.SetParent(Fahter.transform);
        //}

    }

    //当鼠标结束拖动时调用   对应接口  IEndDragHandler
    public void OnEndDrag(PointerEventData eventData)
    {
        offset = Vector2.zero;
        //if (!this.name.Contains("TwoArrows"))
        //{
        //    this.gameObject.transform.SetParent(Fahter.transform);
        //}
      
    }
    void Update()
    {
  
       if (Input.GetAxis("Mouse ScrollWheel") > 0.1)
        {
            if (imgRect.localScale.x <= 5)
            {
                imgRect.localScale += new Vector3(0.1f, 0.1f, 0.1f);


            }
        }
        else if (Input.GetAxis("Mouse ScrollWheel") < -0.1)
        {
            if (imgRect.localScale.x >= .5)
            {
                imgRect.localScale -= new Vector3(0.1f, 0.1f, 0.1f);
            }
        }
        if (Input.GetKeyDown(KeyCode.Escape))
        {
            GameObject.Find("Main Camera").GetComponent<MouseFollowRotation>().enabled = true;
            GameObject.Find("Main Camera").GetComponent<MiddleButtonDrag>().enabled = true;
            this.gameObject.SetActive(false);
        }
       
    }
    
}