GridView实现图标显示

package com.example.administrator.gridview;

import android.content.Context;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.SimpleAdapter;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


public class MainActivity extends Activity {
    private GridView gridView;
    private Context mContext;

    private List<Map> data_list;

    private Object[]pics = {R.drawable.address_book,R.drawable.calendar,R.drawable.camera,R.drawable.clock,R.drawable.games_control,R.drawable.messenger,R.drawable.ringtone,R.drawable.settings,R.drawable.speech_balloon,R.drawable.weather,R.drawable.world,R.drawable.youtube};
    private String[]texts = {"地址簿","日历","照相机","时钟","游戏","信使","铃声","设置","微信","天气","地图","YouTube"};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = this;
        gridView = (GridView)findViewById(R.id.gridView);

        data_list = new ArrayList<Map>();
        SimpleAdapter adapter = new SimpleAdapter(mContext,getData(),R.layout.item,new String[]{"pic","text"},new int[]{R.id.pic,R.id.text});
        gridView.setAdapter(adapter);

        gridView.setOnItemClickListener(new GridView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, int position, long id) {
                HashMap_item = (HashMap)gridView.getItemAtPosition(position);
                Toast.makeText(mContext,_item.get("pic") + "=>" + _item.get("text"),Toast.LENGTH_SHORT).show();
            }
        });
    }

    private List<Map> getData(){
        int length = pics.length;
        for (int i=0  ; i < length ; i++){
            Mapdata = new HashMap();
            data.put("pic",pics[i]);
            data.put("text",texts[i]);
            data_list.add(data);
        }
        return data_list;
    }
}

item.xml