Run loop every second java

Question

int delay = 1000; // delay for 1 sec. 
int period = 10000; // repeat every 10 sec. 
Timer timer = new Timer(); 
timer.scheduleAtFixedRate(new TimerTask() 
    { 
            


        

Answer 1

There several mistakes you have done:

1. You should never invoke Thread.sleep() on the main thread (and you should never block it for a long time as well). Once main thread is blocked for more then 5 seconds, an ANR (application not responding) happens and it is force closed.

2. You should avoid using Timer in android. Try Handler instead. Good thing about handler is that it is created on the main thread -> can access Views (unlike Timer, which is executed on its own thread, which cannot access Views).

   class MyActivity extends Activity {
   
       private static final int DISPLAY_DATA = 1;
       // this handler will receive a delayed message
       private Handler mHandler = new Handler() {
           @Override
           void handleMessage(Message msg) {
               if (msg.what == DISPLAY_DATA) displayData();
           }
        };
   
        @Override
        void onCreate(Bundle b) {
            //this will post a message to the mHandler, which mHandler will get
            //after 5 seconds
            mHandler.postEmptyMessageDelayed(DISPLAY_DATA, 5000);
        }
    }