Android TimerTask only runs once, but sometimes a bit more often

Question

my TimerTask in Android runs most of the time just once, sometimes it starts a bit more often and stops then.

Basically I want an App to track the sensor-data of the device.

I have a MainActivity and 2 Services for Sensoring and Logging.

Here's the logging part:

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    if (!started) {
        started = true;
    }
    logfile = new File(Environment.getExternalStorageDirectory() + File.separator + "log.csv");
    if (!logfile.exists()) {
        try {
            logfile.createNewFile();
            //FileWriter fw = new FileWriter(logfile, true);
            //fw.write("Modell;GPS-Zeit[Millis];Lat;Lon;Alt;Speed;AccX;AccY;AccZ;LinAccX;LinAccY;LinAccZ\n");
            //fw.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    myTimer = new Timer();
    myTimer.schedule(pingTimerTask, 1000, 1000);
    myTimer.schedule(logTimerTask, 500,500);
    Toast.makeText(this, "LogService started", Toast.LENGTH_SHORT).show();
    Log.i(T, "LogService started");
    return super.onStartCommand(intent, flags, startId);
}

and here's the TimerTask:

TimerTask logTimerTask = new TimerTask() {
    @Override
    public void run() {
        try {
            logData();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
};

logdata()

private void logData() {
        currentMsg = createMsg();
        try {
            FileWriter fw = new FileWriter(logfile, true);
            fw.write(currentMsg + "\n");
            fw.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        logSize+=currentMsg.length();
        for (Listener l : listener) {
            l.logged(logfile.toString(), logSize);
        }
    }

Can anyone tell me what's wrong with the Timer?

Thanks

score 0 · Accepted Answer · answered Nov 08 '12 at 18:47

0

Most likely it is because you are returning the default values on onStartCommand:

return super.onStartCommand(intent, flags, startId);

Should be replaced by:

return START_STICKY;

This makes the service to continue running until it is explicitly stopped, so you'll have to stop it manually somewhere else, do not let it runing forever.

answered Nov 08 '12 at 18:47

Aerinx

152
4

that sounds correct, I just tried it but I still got just one entry in the logfile :-( – Philipp Nov 09 '12 at 00:45
solved it with a handler: public void run() { /* do what you need to do */ try { sendData(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } /* and here comes the "trick" */ handler.postDelayed(this, 500); } ............. handler.postDelayed(logTimerTask, 500); – Philipp Nov 12 '12 at 02:22

Android TimerTask only runs once, but sometimes a bit more often

1 Answers1