问题描述

进入页面虚拟机崩溃，找不到错误，求大神帮改下源码，谢谢啦

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.View;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

public class StartCanteenActivity extends Activity
{
private static final String urlPath = ""http://www.imooc.com/api/teacher?type=4&num=30"";
//private static final String urlPath = ""http://14.117.17.161/json.php"";
private RecyclerView mRvDemoMain;
private MyRecyclerAdapter mAdapter;
private List mList;

@Overrideprotected void onCreate(Bundle savedInstanceState){    super.onCreate(savedInstanceState);    setContentView(R.layout.canteen);    mRvDemoMain = (RecyclerView) findViewById(R.id.canteen_recyclerview);    new NewAsyncTask().execute(urlPath);    initView();}/** * 初始化本页面的控件 */private void initView() {    mRvDemoMain.setAdapter(mAdapter);    // 设置RecyclerView的布局管理器    mRvDemoMain.setLayoutManager(new StaggeredGridLayoutManager(3 StaggeredGridLayoutManager.VERTICAL));    mRvDemoMain.setItemAnimator(new DefaultItemAnimator());    // 调用Adapter中的设置监听器的方法    mAdapter.setOnItemClickListener(new MyRecyclerAdapter.OnItemClickListener() {        @Override        public void onItemClick(View view int position) {            Toast.makeText(StartCanteenActivity.thisclick : "" + position Toast.LENGTH_SHORT).show();        }    });}/** * 实现网络的异步访问 */class NewAsyncTask extends AsyncTask<String Void List<NewsBeam>>{    @Override    protected void onPostExecute(List<NewsBeam> newsBeams)    {        super.onPostExecute(newsBeams);        MyRecyclerAdapter adapter = new MyRecyclerAdapter(StartCanteenActivity.this newsBeams mRvDemoMain);        mRvDemoMain.setAdapter(adapter);    }    @Override    protected List<NewsBeam> doInBackground(String... params)    {        return getJsonData(params[0]);    }    /**     * 从 URL 中获取数据     *     * @param url     * @return     */    private List<NewsBeam> getJsonData(String url)    {        List<NewsBeam> newsBeamsList = new ArrayList<NewsBeam>();        try        {            String jsonString = readStream(new URL(urlPath).openStream());            JSONObject jsonObject;            NewsBeam newsBeam;            jsonObject = new JSONObject(jsonString);            JSONArray jsonArray = jsonObject.getJSONArray(""data"");            for(int i = 0; i < jsonArray.length(); i++)            {                jsonObject = jsonArray.getJSONObject(i);                newsBeam = new NewsBeam();                newsBeam.newsIconUrl = jsonObject.getString(""picSmall"");                newsBeam.newsTitle = jsonObject.getString(""name"");                newsBeamsList.add(newsBeam);            }        }        catch(IOException e)        {            e.printStackTrace();        }        catch(JSONException e)        {            e.printStackTrace();        }        return newsBeamsList;    }    /**     * 从 inpustStream 获取的信息     *     * @param is     * @return     */    private String readStream(InputStream is)    {        InputStreamReader isr;        String result = """";        try        {            isr = new InputStreamReader(isutf-8"");            BufferedReader br = new BufferedReader(isr);            String line = """";            while((line = br.readLine()) != null)            {                result += line;            }        }        catch(UnsupportedEncodingException e)        {            e.printStackTrace();        }        catch(IOException e)        {            e.printStackTrace();        }        return result;    }}

}

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MyRecyclerAdapter extends RecyclerView.Adapter {
protected LayoutInflater mLayoutInflater;
private Context mContext;
protected List mList;
private List mHeights; // 随机高度的集合
private ImgLoader mImgLoader;
private int mStart;
private int mEnd;
public static String[] URLS;
private boolean mFirstIn;
private MyRecyclerAdapter(List mList) {
this.mList = mList;
}

/** * 自定义一个OnItemClickListener的回调接口 */public interface OnItemClickListener{    void onItemClick(View view int position);}/** * 创建接口的成员变量 */private OnItemClickListener mOnItemClickListener;/** * 设置监听器的方法 * @param listener listener */public void setOnItemClickListener(OnItemClickListener listener){    this.mOnItemClickListener = listener;}/** * 构造方法 * @param context context * @param data data */public MyRecyclerAdapter(Context context List<NewsBeam> dataRecyclerView recyclerView) {    this.mContext = context;    this.mList = data;    mLayoutInflater = LayoutInflater.from(mContext);    mImgLoader = new ImgLoader(recyclerView);    mLayoutInflater = LayoutInflater.from(mContext);    mHeights = new ArrayList<Integer>();    // 向随机高度集合中添加随机数(100 ~ 400)    for (int i = 0; i < mList.size(); i++) {        mHeights.add((int) (100 + Math.random() * 300));    }    URLS = new String[data.size()];    for(int i = 0; i < data.size(); i++)    {        URLS[i] = data.get(i).newsIconUrl;    }    mFirstIn = true;}/** * RecyclerView中条目的数量 * * @return count */@Overridepublic int getItemCount() {    return mList.size();}/** * 创建ViewHolder * * @param parent   parent * @param viewType viewType * @return holder */@Overridepublic MyRecyclerHolder onCreateViewHolder(ViewGroup parent int viewType) {    // zz 测试    System.out.println(""====onCreateViewHolder : "" + viewType + "" == "" + parent);    View view = mLayoutInflater.inflate(R.layout.recycler_item parent false);    MyRecyclerHolder mHolder = new MyRecyclerHolder(view);    return mHolder;}/** * 绑定ViewHolder * * @param holder   holder * @param position position */@Overridepublic void onBindViewHolder(final MyRecyclerHolder holder final int position) {    // 为ViewHolder的父控件(也即一条Item)设置高度    ViewGroup.LayoutParams lp = holder.itemView.getLayoutParams();    lp.height = mHeights.get(position);    holder.itemView.setLayoutParams(lp);    holder.mIvItem.setImageBitmap(null);    holder.mIvItem.setImageResource(R.mipmap.ic_launcher);    String url = mList.get(position).newsIconUrl;    holder.mIvItem.setTag(url);    mImgLoader.showImgByAysncTask(holder.mIvItem url);    holder.mTvItem.setText(mList.get(position).newsTitle);    // 调用条目的点击事件设置方法    setUpItemEvent(holder);    // zz 测试    System.out.println(""====onBindViewHolder : "" + position + "" == "" + holder);}/** * 设置条目的点击事件(点按) * @param holder holder */protected void setUpItemEvent(final MyRecyclerHolder holder) {    if (mOnItemClickListener != null) {        holder.itemView.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                int layoutPosition = holder.getLayoutPosition();                mOnItemClickListener.onItemClick(holder.itemView layoutPosition);            }        });    }}/** * RecyclerView的ViewHolder类 */public class MyRecyclerHolder extends RecyclerView.ViewHolder {    ImageView mIvItem;    TextView mTvItem;    public MyRecyclerHolder(View itemView) {        super(itemView);        mIvItem = (ImageView) itemView.findViewById(R.id.id_image);        mTvItem = (TextView) itemView.findViewById(R.id.id_name);    }}

}

解决方案

代码太多，建议自己调试