java - TimerTask cancel / restart -

in app use timertask repeat action every x seconds, want stop timertask button , run again pressing another. here have far:

public class mainactivity extends activity {  timer tempogatto = new timer(); timertempogatto timertempogatto = new timertempogatto();  @override protected void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.activity_main);   final textview  start = (textview)findviewbyid(r.id.start); start.setontouchlistener(new ontouchlistener() { @override public boolean ontouch(view v, motionevent event) { // todo auto-generated method stub if(event.getaction() == motionevent.action_down){      tempogatto.schedule(timertempogatto, 0, 20000);           }      return true; }  });    final textview  stop = (textview)findviewbyid(r.id.stop); stop.setontouchlistener(new ontouchlistener() { @override public boolean ontouch(view v, motionevent event) { // todo auto-generated method stub if(event.getaction() == motionevent.action_down){      tempogatto.cancel                          }   return true; }  });         (.....)      private class timertempogatto extends timertask {         @override         public void run() {             runonuithread(new runnable() {                 @override                 public void run() {                      //code want repeat every 20 second                    }             });         }     } 

naturally when click stop textview , start textview restart timertask, give me

java.lang.illegalstateexception: timer canceled  

in android, threads , timers not reusable, thread in timertask can't reused. every time want re-launch timertask, need instantiate new one.

so add these lines

tempogatto = new timer(); timertempogatto = new timertempogatto(); 

before one

tempogatto.schedule(timertempogatto, 0, 20000);