unityzgy/Assets/Scripts/UIScripts/Teacher/DragIcon.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;

public class DragIcon : IconBase
{
    protected Vector2 offsetPos;  //临时记录点击点与UI的相对位置
    protected bool isOnMap;//放置在固定位置
    protected bool keepLocalScale;//是否保持自身缩放 true随父物体缩放  false父物体缩放时始终保持当前的大小 
    protected bool isAdded;//已经添加到记录中
    protected List<RaycastResult> results = new List<RaycastResult>();//点击时触发的所有UI层级
    // Start is called before the first frame update
    protected virtual void Start()
    {
        if (!isOnMap)
        {
            transform.position = (Vector2)Input.mousePosition;
            offsetPos = (Vector2)Input.mousePosition - (Vector2)transform.position;
        }
        float parentScale = this.transform.parent.localScale.x;
        this.transform.localScale = new Vector3(1.0f / parentScale, 1.0f / parentScale, 1);
    }

    // Update is called once per frame
    protected virtual void Update()
    {
        if (!isOnMap)
        {
            transform.position = (Vector2)Input.mousePosition - offsetPos;
        }

        if (!keepLocalScale)
        {
            float parentScale = this.transform.parent.localScale.x;
            this.transform.localScale = new Vector3(1.0f / parentScale, 1.0f / parentScale, 1);
        }
    }

    protected void GetMouseRaycastAll()
    {
        PointerEventData eventDataCurrentPosition = new PointerEventData(EventSystem.current);
        eventDataCurrentPosition.position = Input.mousePosition;
        EventSystem.current.RaycastAll(eventDataCurrentPosition, results);
    }

   //设置初始化位置 并固定在该位置 关闭拖拽逻辑
    public void SetFixedAnchoredPos(Vector2 anchorPos)
    {
        this.GetComponent<RectTransform>().anchoredPosition = anchorPos;
        isOnMap = true;
        isAdded = true;
    }

    /// <summary>
    /// 被对象池收回时初始化参数  
    /// </summary>
    protected virtual void OnDisable()
    {
        isOnMap = false;
        isAdded = false;
    }


}