实现ListView图文混排 —— 获取Json数据

来源：互联网发布：杭州淘宝美工培训编辑：程序博客网时间：2024/05/16 09:22

先新建一个布局文件和NewsBean类

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="horizontal" >    <ImageView        android:id="@+id/iv_image"        android:layout_width="64dp"        android:layout_height="64dp"        android:src="@drawable/ic_launcher" />    <LinearLayout        android:layout_width="match_parent"        android:layout_height="64dp"        android:gravity="center"        android:orientation="vertical"        android:paddingLeft="10dp" >        <TextView            android:id="@+id/tv_title"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:gravity="center_horizontal"            android:maxLines="1"            android:text="Title"            android:textSize="20sp" />        <TextView            android:id="@+id/tv_content"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:maxLines="2"            android:text="Content"            android:textSize="15sp" />    </LinearLayout></LinearLayout>

public class NewsBean {public String newsIconUrl;public String newsTitle;public String newsContent;}

在activity_main.xml中，引用前面新建的布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context=".MainActivity" >    <ListView        android:id="@+id/lv_main"        android:layout_width="match_parent"        android:layout_height="wrap_content" >    </ListView></LinearLayout>

在MainActivity中写相应的代码。

public class MainActivity extends Activity {private ListView listView;public static String URL = "http://www.imooc.com/api/teacher?type=4&num=30";@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);listView = (ListView) findViewById(R.id.lv_main);new NewsAsyncTask().execute(URL);}private List<NewsBean> getJsonData(String url) {List<NewsBean> newsBeansList = new ArrayList<NewsBean>();try {String jsonString = readStream(new URL(url).openStream());// 此句和url.openConnection().getInputStream()相同，可根据URL直接联网获取网络数据// 返回值的类型为InputStreamLog.d("abc", jsonString);} catch (IOException e) {e.printStackTrace();}return newsBeansList;}private String readStream(InputStream is) {String result = "";InputStreamReader isr;try {String line = "";isr = new InputStreamReader(is, "utf-8");BufferedReader br = new BufferedReader(isr);while ((line = br.readLine()) != null) {result += line;}} catch (UnsupportedEncodingException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return result;}class NewsAsyncTask extends AsyncTask<String, Void, List<NewsBean>> {@Overrideprotected List<NewsBean> doInBackground(String... params) {// TODO Auto-generated method stubreturn getJsonData(params[0]);}}}

这是如何通过InputStream读取网络信息的呢？

传进一个InputStream字节流，通过InputStreamReader将字节流转化为字符流，再通过BufferedReader将字节流以Buffer形式读取出来，最终拼接到result中。

最后，要记得在清单文件中添加权限。

 <uses-permission android:name="android.permission.INTERNET" />

0 0