ListView和网络请求，listVIew的优化ViewHolder

最近在做一个关于ListView和网络请求的一个小demo，话不多说，上马，第一次写博客，不足之处望大家见谅。

MainActivity.java
public class MainActivity extends AppCompatActivity {
    private String[] data ={};
    private MyHandler handler;
    ListView listView;
    private MyAdapter adapter;
    ArrayList<IconTextBean.bean> list = new ArrayList<>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        handler = new MyHandler();
        listView = findViewById(R.id.showListView);
        adapter = new MyAdapter(this,list);
        listView.setAdapter(adapter);
//网络请求数据，通过Java Bean进行处理
        getNetworkData();
    }

//从网络得到的数据进行解析，
    class  MyHandler extends  Handler{
        @Override
        public void handleMessage(Message msg) {
            String s = (String)msg.obj;
            JsonObject jsonObject = (JsonObject) new JsonParser().parse(s);
            try {
                JsonArray jsonArray = jsonObject.get("data").getAsJsonArray();
                Gson gson = new Gson();
                //GSON直接解析成对象
                list = gson.fromJson(jsonArray, new TypeToken<List<IconTextBean.bean>>() {}.getType());
                if (list.size()>0){
                adapter.update(list);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    public  void getNetworkData (){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    URL url = new URL("可以用一些免费的天气JSON API");
                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();//开启连接
                    //超时时间
                    connection.setConnectTimeout(3000);
                    //表示设置本次http请求使用GET方式
                    connection.setRequestMethod("GET");
//                    connection.connect();//连接服务器
                    if (connection.getResponseCode() == 200) {
                        //使用字符流形式进行回复
                        InputStream is = connection.getInputStream();
                        //读取信息BufferReader
                        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                        StringBuffer buffer = new StringBuffer();
                        String readLine = "";
                        while ((readLine = reader.readLine()) != null) {
                            buffer.append(readLine);
                        }
                        is.close();
                        reader.close();
                        connection.disconnect();
                        Message msg = handler.obtainMessage();
                        msg.obj= buffer.toString();
                        handler.sendMessage(msg);
                        Log.d("Kerwin", buffer.toString());
                    } else {
                        Log.d("Kerwin", "ERROR CONNECTED");
                    }
                }  catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }

MyAdapter.java

public class MyAdapter extends BaseAdapter {
    private ArrayList<IconTextBean.bean> datas;
    private Context mContext;
    public MyAdapter(Context context, ArrayList<IconTextBean.bean> list) {
        this.mContext = context;
        this.datas = list;
    }
    //异步更新数据
    public void update( ArrayList<IconTextBean.bean> list) {
        this.datas = list;
        //填充数据
        notifyDataSetChanged();
    }
    @Override
    public int getCount() {
        return datas.size();
    }
    @Override
    public Object getItem(int i) {
        return datas.get(i);
    }
    @Override
    public long getItemId(int i) {
        return i;
    }
    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        ViewHolder vh  = new ViewHolder();
        if (view == null) {
            view = LayoutInflater.from(mContext).inflate(R.layout.icon_text, null);
            vh.pic = (ImageView) view.findViewById(R.id.car_icom);
            vh.name = (TextView) view.findViewById(R.id.car_name);
            view.setTag(vh);
        } else {
            vh = (ViewHolder) view.getTag();
        }
        vh.name.setText(datas.get(i).getName());
        Glide.with(mContext)
            .load(datas.get(i).getPicurl())
            .into(vh.pic);
        return view;
}
    class ViewHolder {
        TextView name;
        ImageView pic;
    }

AndroidManifest加入权限<uses-permission android:name="android.permission.INTERNET"/>

activity_main.xml

    <ListView
        android:id="@+id/showListView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
icon_text.xml这里我是用了horizontal这个属性让得到的图标和文字横向排列，具体需要什么样的布局自己定
<ImageView
    android:id="@+id/car_icom"
    android:layout_width="60dp"
    android:layout_height="60dp" />
<TextView
    android:id="@+id/car_name"
    android:layout_marginLeft="20dp"
    android:textColor="@android:color/black"
    android:textSize="18sp"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    />

Bean文件就不放出来