Android应用开发之获取网络数据

J2SE实现网络图片的获取

 public static void main(String[] args) throws Exception {
       String path = "http://res.img.ifeng.com/2011/1219/xes_bb10a1495fa8e7f76415023d177585d0.jpg";

       URL url = new URL(path);

       HttpURLConnection conn = (HttpURLConnection) url.openConnection();
       conn.setRequestMethod("GET");
       conn.setConnectTimeout(5*1000);
       InputStream inStream = conn.getInputStream();

       ByteArrayOutputStream outStream = new ByteArrayOutputStream();
       byte[] buffer = new byte[1024];

       int len=0;
       while((len=inStream.read(buffer))!=-1){
           outStream.write(buffer,0,len);
       }

       byte[] data = outStream.toByteArray();

       File f = new File("pic.jpg");
       FileOutputStream fos = new FileOutputStream(f);
       fos.write(data);
       fos.close();
    }

Androd中获取网络图片

资源

 <string name="btn_text">显示网络图片</string>
    <string name="error">下载图片失败！！</string>

布局

 <Button
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:text="@string/btn_text"
         android:id="@+id/showBtn"
         />

     <ImageView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:id="@+id/imageView"
         />

添加ImageService类

 package cn.class3g.service;
 …
 public class ImageService {
     public static byte[] getImage(String path) throws Exception{
        URL url = new URL(path);
        //get //post
        HttpURLConnection conn = (HttpURLConnection)url.openConnection();
        conn.setRequestMethod("GET");
        conn.setConnectTimeout(5*1000);
        InputStream inStream = conn.getInputStream();

        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while( (len = inStream.read(buffer)) !=-1 ){
            outStream.write(buffer, 0, len);
        }
        byte[] data = outStream.toByteArray();//图片的二进制数据
        outStream.close();
        inStream.close();
        return data;
     }
 }

Activity

 public void onClick(View v) {
        String path = "http://res.img.ifeng.com/2011/1221/xes_5a3a1d15ffb4b856a02237cdd79d4e41.jpg";

        try {
            byte[] data = ImageService.getImage(path);

            Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
            imgView.setImageBitmap(bitmap);

        } catch (Exception e) {
 //         e.printStackTrace();
            Log.e("TAG", e.toString());
            Toast.makeText(this, R.string.error, 1).show();
        }
     }

Androd中获取网页代码

布局

 <Button
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/btn_text"
        android:id="@+id/showBtn"
        />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView"
        />

代码：在前面的ImageService.getImage（）方法基础上修改即可

HtmlService

 public class HtmlService {
     /**
      * 获取给定路径的html代码
      * @param path 网页路径
      * @return
      * @throws Exception
      */
     public static String getHtml(String path) throws Exception{
        URL url = new URL(path);
        //get //post
        HttpURLConnection conn = (HttpURLConnection)url.openConnection();
        conn.setRequestMethod("GET");
        conn.setConnectTimeout(5*1000);
        InputStream inStream = conn.getInputStream();

        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while( (len = inStream.read(buffer)) !=-1 ){
            outStream.write(buffer, 0, len);
        }
        byte[] data = outStream.toByteArray();//网页的二进制数据
        outStream.close();
        inStream.close();
        return new String(data, "gb2312");
     }
 }

ShowHtmlActivity

 public void onClick(View v) {
     String path = pathText.getText().toString();
     try {
        String htmlcode = HtmlService.getHtml(path);
        resultView.setText(htmlcode);
     } catch (Exception e) {
        Log.e(TAG, e.toString());
        Toast.makeText(ShowHtmlActivity.this, R.string.error, 1).show();
     }
 }