3个步骤教你用listView显示网络图片

1. 从网络获取图片

 

/**
     * 获取网络图片
     * @param path 网络图片路径
     * @return
     * @throws Exception
     */
    public static byte[] getImage(String path) throws Exception{
        URL url = new URL(path);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setConnectTimeout(5 * 1000);
        conn.setRequestMethod("GET");
        InputStream inStream = conn.getInputStream();
        if(conn.getResponseCode()==200){
            return StreamTool.readStream(inStream);
        }
        return null;
    }

 

2. 读取流中数据

/**
     * 读取流中的数据
     * @param inStream
     * @return
     * @throws Exception
     */
    public static byte[] readStream(InputStream inStream) throws Exception{
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while( (len=inStream.read(buffer)) != -1){
            outStream.write(buffer, 0, len);
        }
        outStream.close();
        inStream.close();
        return outStream.toByteArray();
    }

 

3. 在ListView中显示

 

public class MainActivity extends Activity {
    private EditText pathText;
    private ImageView imageView;
     
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
         
        pathText = (EditText) this.findViewById(R.id.path);
        imageView = (ImageView) this.findViewById(R.id.imageView);
        Button button = (Button) this.findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
             
            public void onClick(View v) {
                String path = pathText.getText().toString();
                try {
                    byte[] data = ImageService.getImage(path);
                    if(data!=null){
                        Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);//构造一张位图
                        imageView.setImageBitmap(bitmap);//完成图片的显示
                    }else{
                        Toast.makeText(MainActivity.this, R.string.imageerror, 1).show();
                    }
                } catch (Exception e) {
                    Toast.makeText(MainActivity.this, R.string.neterror, 1).show();
                    e.printStackTrace();
                }
            }
        });
    }
}

 

大功告成！