Rescheduling Timer in android
I'm trying to have a Timer that schedules a TimerTask for successive executions. I don't know how many times it'll work. on a user click, the Timer will stop, and on another, it'll run again. Everything works until stopping, when i reschedule, I get exceptions saying that the Timer is canceled or already scheduled. How do I make it stop and run again? I've tried everything I could think of and it's still not working.
This is the latest code I'm trying:
Timer myTimer;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
cameraTimedTask = new camera(this);
myTimer = new Timer("cameraTimer");
Button b=(Button)findViewById(R.id.b);
b.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
myTimer.purge();
myTimer.scheduleAtFixedRate(cameraTimedTask, 1000, 5000);
}
});
Button bb=(Button)findViewById(R.id.button);
bb.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
myTimer.cancel();
myTimer.purge();
myTimer = null;
myTimer = new Timer("camerasTimer");
Log.i("Check","[main]"+" timer stopped");
}
});
}
You can't reschedule a TimerTask. You need a new one every time. Moreover, it is advised in android to use Handlers and postDelayed.
in my opinion, try to use Countdown timer instead of timer
quick usage:
new CountDownTimer(30000, 1000) {
public void onTick(long millisUntilFinished) {
mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
}
public void onFinish() {
mTextField.setText("done!");
}
}.start();
or if you want something more complex:
public class MyCountDownTimer extends CountDownTimer {
public MyCountDownTimer(long startTime, long interval) {
super(startTime, interval);
}
@Override
public void onFinish() {
text.setText("Time's up!");
}
@Override
public void onTick(long millisUntilFinished) {
text.setText("" + millisUntilFinished / 1000);
}
}
The perfect solution for you would be to use a Handler
private Runnable runnable;
private Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
handler = new Handler();
runnable = new Runnable() {
@Override
public void run() {
// run code delayed code in here once
}
};
Then in your multirepeating code you have to remove the posted callbacks and then reschedule for execution.
handler.removeCallbacks(runnable);
handler.postDelayed(runnable, 200);
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