/** *  * 访问网络的操作，必须放在工作线程中完成 * */public class MainActivity extends Activity {    static List<HashMap<String, String>> list;    static List<String> userList2 = new ArrayList();     private static final int LOADSUCCESS=0x1;    private static ImageView iv;    private static TextView tv;    private final myhandler handler=new myhandler(this);    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        iv=(ImageView) findViewById(R.id.imageView1);        new Thread(new Runnable() {            public void run() {                try {                    URL url=new URL("http://files.cnblogs.com/files/hyyweb/welcome.bmp");                    InputStream in=url.openStream();                    Bitmap bitmap=BitmapFactory.decodeStream(in);                    String result="";                    Message message= handler.obtainMessage(LOADSUCCESS, bitmap);                    handler.sendMessage(message);                } catch (MalformedURLException e) {                    e.printStackTrace();                } catch (IOException e) {                    e.printStackTrace();                }            }        }).start();    }    private static class myhandler extends Handler{                private final WeakReference<MainActivity> weakReference;        public myhandler(MainActivity mainActivity){            weakReference=new WeakReference<MainActivity>(mainActivity);        }                public void handleMessage(Message msg) {            MainActivity mainActivity=weakReference.get();            if(mainActivity!=null){                switch (msg.what) {                case LOADSUCCESS:                    MainActivity.iv.setImageBitmap((Bitmap) msg.obj);                    break;                }            }        }    }}