求助 报错是 String text2=listView.getItemAtPosition(position)+"";

Question

package com.example.zeroking.demolistview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
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 AppCompatActivity implements AdapterView.OnItemClickListener,AbsListView.OnScrollListener
{
   private ListView listView;
   private ArrayAdapter arrayAdapter;
   private SimpleAdapter simpleAdapter;
   private List<Map<String,Object>> dataList;






   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       ListView listView=(ListView)findViewById(R.id.LV);
       String[] arr_data={"慕课1","慕课2","慕课3","慕课4","慕课5","慕课6"};
       //新建一个适配器
       //new ArrayAdapter(上下问，当前ListView加载每项的布局，数据源)
       arrayAdapter=new ArrayAdapter(this,android.R.layout.simple_list_item_1,arr_data);
       //listView.setAdapter(arrayAdapter);
       dataList=new ArrayList<Map<String,Object>>();
       simpleAdapter=new SimpleAdapter(this,getData(),R.layout.simplelayout,new String[]{"pic","text"},new int[]{R.id.pic,R.id.text});
       listView.setAdapter(simpleAdapter);
       listView.setOnItemClickListener(this);



   }
   private List<Map<String,Object>> getData(){

       for(int i=0;i<20;i++){
           Map<String,Object>map=new HashMap<String,Object>();
           map.put("pic",R.drawable.gets);
           map.put("text","慕课网"+i);
           dataList.add(map);
       }

       /*
       Map<String,Object>map1=new HashMap<String,Object>();
       map1.put("pic",R.drawable.gets);
       map1.put("text","慕课网"+1);
       dataList.add(map1);
       Map<String,Object>map2=new HashMap<String,Object>();
       map2.put("pic",R.drawable.gets);
       map2.put("text","哈哈哈哈");
       dataList.add(map2);
       */

       return dataList;
   }


   @Override
   public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
       String text2=listView.getItemAtPosition(position)+"";
       Toast.makeText(this,"position="+position+" text="+text2,Toast.LENGTH_SHORT).show();
       Log.i("toast",String.valueOf(position));
   }

   @Override
   public void onScrollStateChanged(AbsListView view, int scrollState) {

   }

   @Override
   public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

   }
}

Answer 1

看着没什么问题啊