NGUI背包中物品拖拽交互练习

NGUI背包，物品随机生成
实现拖拽，物品之间互换位置。
物品上脚本KnapSackItem.cs

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

public class KnapSackItem : UIDragDropItem {


    public UISprite sprite;//获取此物体上UISprit组件
    public UILabel label;//获取表示物体数量的label组件
    private int count = 1;//用来作为物体数量的计数器

    public void AddCount(int number=1)
    {
        count += number;
        label.text = count + " ";
    }

    protected override void OnDragDropRelease(GameObject surface)
    {
        base.OnDragDropRelease(surface);

        if (surface.tag == "Cell")
        {
            this.transform.parent = surface.transform;
            this.transform.localPosition = Vector3.zero;
        }
        else if (surface.tag == "KnapsackItem")
        {
            Transform parent = surface.transform.parent;
            surface.transform.parent = this.transform.parent;
            surface.transform.localPosition = Vector3.zero;
            this.transform.parent = parent;
            this.transform.localPosition = Vector3.zero;
        }
    }
}

物品面板上脚本Knapsack.cs

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

public class Knapsack : MonoBehaviour {

    public GameObject[] cells;//需指定目标物品格子
    public string[] equipmentsName;//添加几种物品的sprite名称
    public GameObject item;//物品预制体

	void Update () {
        if (Input.GetKeyDown(KeyCode.A))//按下a键模拟拾取物品
        {
            Pickup();
        }
    }

    public void Pickup()
    {
        int index = Random.Range(0,equipmentsName.Length);//随机拾取物品池中物体
        string name = equipmentsName[index];//对应物品名称
        bool isFind = false;
        for (int i = 0; i < cells.Length; i++)
        {
            if (cells[i].transform.childCount > 0)
            {
                KnapSackItem item = cells[i].GetComponentInChildren<KnapSackItem>();
                if (item.sprite.spriteName==name)
                {
                    isFind = true;
                    item.AddCount(1);
                    break;
                }
            }
        }
        if (isFind==false)
        {
            for (int i = 0; i < cells.Length; i++)
            {
                if (cells[i].transform.childCount == 0)//检测当前位置是否有物体
                {
                    GameObject go = NGUITools.AddChild(cells[i], item);
                    go.GetComponent<UISprite>().spriteName = name;
                    go.transform.localPosition = Vector3.zero;
                    break;
                }
            }
        }
    }
}