using System.Collections;

using System.Collections.Generic;

using UnityEngine;

using UnityEngine.UI;

using UnityEngine.EventSystems;

/// <summary>

/// **************************UGUI拖动图片,脚本挂在Image上即可*********************************

/// </summary>

public class TuoDongWuPin : MonoBehaviour, IDragHandler, IBeginDragHandler, IEndDragHandler

{

    //需要被实例化的与制体

    //public GameObject YuSheWu;

    //实例化后的对象

    private Image img;

    Vector3 offPos;//存储按下鼠标时的图片-鼠标位置差

    Vector3 arragedPos; //保存经过整理后的向量，用于图片移动

    /// <summary>

    /// 开始拖拽的时候

    /// </summary>

    /// <param name="eventData"></param>

    public void OnBeginDrag(PointerEventData eventData)

    {

        if (RectTransformUtility.ScreenPointToWorldPointInRectangle(transform.GetComponent<RectTransform>(), Input.mousePosition

     , eventData.enterEventCamera, out arragedPos))

        {

            offPos = transform.position - arragedPos;

        }

    }

    /// <summary>

    /// 拖拽中

    /// </summary>

    /// <param name="eventData"></param>

    public void OnDrag(PointerEventData eventData)

    {

        transform.position = offPos + Input.mousePosition;

    }

    /// <summary>

    /// 拖拽结束

    /// </summary>

    /// <param name="eventData"></param>

    public void OnEndDrag(PointerEventData eventData)

    {

        transform.position = transform.parent.transform.position;

    }

}