Fragment中setAdapter() ListView报空指针，几天没解决，求大神！！！

阿不阿 2014-04-04 09:38:52

在Fragment中使用ListView，测试了很久，实在不知道哪里有空指针的问题。以下是类源码：



package net.iwetao.order;



import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;



import org.json.JSONArray;

import org.json.JSONObject;



import net.iwetao.R;

import android.os.Bundle;

import android.support.v4.app.Fragment;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ListView;

import android.widget.SimpleAdapter;

import android.widget.Toast;

import net.iwetao.init.RedefineHttpRequest;



public class Order extends Fragment {



    private ListView orderListView;

	

	@Override

	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 

	{

		return inflater.inflate(R.layout.index_order, container, false);

	}

	

	@Override

	public void onActivityCreated(Bundle savedInstanceState)

	{

		// TODO Auto-generated method stub

		super.onActivityCreated(savedInstanceState);

	   // 其他操作

	   String url = "http://www.91weida.com/androidTest.php";

	   HashMap<String,Object> param = new HashMap<String,Object>();

	   param.put("act","getOrder");

	   param.put("page",1);

	   try

	   {

		  this.getOrders(url,param);

	   }

	   catch(Exception e)

	   {

		   android.util.Log.i("sysEr",e.toString());

		   Toast.makeText(this.getActivity(),"服务器连接出错", Toast.LENGTH_SHORT).show();

	   }

	   

	   //TextView orderList = (TextView)getActivity().findViewById(R.id.init_test);

	   /* 设置订单管理的监听事件 */

	   /*orderList.setOnClickListener(new View.OnClickListener() {

		  @Override

		  public void onClick(View v) {

			// TODO Auto-generated method stub

			

		  }

	   });

	   */

	}

	

	/*

	 * 获取服务器订单 

	 * @param String url, HashMap<String,Object> data

	 * @void

	 */

	public  void getOrders(String url,HashMap<String,Object> param) throws Exception

	{

		String data = RedefineHttpRequest.HttpPost(url, param);   //取得服务器返回的json

		JSONObject msg = new JSONObject(data);

		int error = msg.getInt("error");

		switch (error)

		{

		case 0:   //返回正确

			JSONArray arr =  msg.getJSONArray("data");

			if(arr.length()==0)   //订单数组为空

			{

			

			}

			else

			{

				List<HashMap<String,Object>> res = new ArrayList<HashMap<String,Object>>();   //定义订单集合数组

				for(int i=0;i<arr.length();i++)

				{

					HashMap<String,Object> map = new HashMap<String,Object>();   

					JSONObject order = arr.getJSONObject(i);   //取得每一个订单

					map.put("order_id", order.getInt("order_id"));

					map.put("goods_name",order.getString("goods_name"));

					map.put("amount", order.getDouble("amount"));

					res.add(map);   //添加到集合数组

				}

                               //res经过打印是绝对不为null的

				SimpleAdapter adapter = new SimpleAdapter(this.getActivity(), res,R.layout.index_order, 

						                     new String[]{"order_id"},

						                     new int[]{R.id.order_id}

				                             ); 

				android.util.Log.i("msg",""+res);

				try

				{

				  orderListView.setAdapter(adapter);	

				}

				catch(Exception e)

				{

					android.util.Log.i("exception",e.toString());   //报空指针问题

				}

			}

			break;

		case 1:   //返回错误

			break;

		case 2:   //未登录

			break;

		}

	} 

}