public class MainActivity extends Activity {
    private Button btnClick=null;
    private Button btnStop=null;
    private TextView tvShow=null;
    private String info="";
    private Timer timer=null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnClick=(Button)findViewById(R.id.btn_click);
        btnStop=(Button)findViewById(R.id.btn_stop);
        tvShow=(TextView)findViewById(R.id.tv_show);

        timer=new Timer();

        btnClick.setOnClickListener(new OnClickListener(){
            public void onClick(View view){
                timer.scheduleAtFixedRate(new MyTask(), 100, 2000);
            }
        });

        btnStop.setOnClickListener(new OnClickListener(){
            public void onClick(View view){
                timer.cancel();
            }
        });

    }
   

    Handler myHandler=new Handler(){
        public void handleMessage(Message msg){
            if(info!=""){
                tvShow.setText(info);
            }
        }
    };

    private class MyTask extends TimerTask{
        public void run(){
            String param="http://192.168.0.116/android/time.php";
            info=HttpHelper.getStringFromNet2(param);
            myHandler.obtainMessage(100).sendToTarget();
        }
    }
}