cancelAlarm method not actually canceling my AlarmManager

Question

I have used this cancelAlarm method from another reputable answer on stack, and it isn't getting the job done, and I am out of ideas of why this isn't working.

I have an activity where one button will start an alarm that will go off every given interval. I then have another button that will cancel that alarm. Here are the buttons first:

    start.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            setupAlarm(10);
        }
    });

    stop.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            try{
                cancelAlarm(ALARM_ID);
            } catch(Exception e){
                Toast.makeText(getApplicationContext(), "ERROR", Toast.LENGTH_SHORT).show();
            }
        }
    });

And here are my setupAlarm and cancelAlarm methods:

private void setupAlarm(int seconds) {
    AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
    Intent i = new Intent(getBaseContext(), AlarmReceiver.class);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(
            MainActivity.this, ALARM_ID, i, PendingIntent.FLAG_UPDATE_CURRENT);
    Calendar t = Calendar.getInstance();
    t.setTimeInMillis(System.currentTimeMillis());

    int interval = seconds*1000;
    am.setRepeating(AlarmManager.RTC_WAKEUP, t.getTimeInMillis(), interval, pendingIntent);
    MainActivity.this.finish();
}

private void cancelAlarm(int alarmId){
    Intent i = new Intent(getBaseContext(), AlarmManager.class);
    PendingIntent sender = PendingIntent.getBroadcast(MainActivity.this, alarmId, i, 0);
    AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    alarmManager.cancel(sender);
    sender.cancel();
}

I remembered to make another alarm manager with the same ID, and call alarmManager.cancel(sender); on the PendingIntent but it doesn't seem to do anything, because my service will start back up anyway.

AlarmReciever class:

public class AlarmReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent)
{
    Context oAppContext = context.getApplicationContext();

    if (oAppContext == null) {
        oAppContext = context;
    }

    Intent serviceIntent = new Intent(oAppContext, MyService.class);
    oAppContext.startService(serviceIntent);
}
}

MyService class:

public class MyService extends Service implements SensorEventListener{

private PowerManager.WakeLock wakeLock;

Sensor mSensor;
SensorManager mSensorManager;
String toastString = "";

@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate(){
    mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
    mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
    mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_NORMAL);

    PowerManager mgr = (PowerManager) getApplicationContext().getSystemService(Context.POWER_SERVICE);
    wakeLock = mgr.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "MyWakeLock");
    wakeLock.acquire();


    Toast.makeText(this, "onCreate Successful", Toast.LENGTH_SHORT).show();
}

@Override
public int onStartCommand(Intent intent, int flags, int startid) {
    Toast.makeText(this, "onStart Successful", Toast.LENGTH_SHORT).show();
    return Service.START_STICKY;
}

@Override
public void onSensorChanged(SensorEvent event) {
    //record some data from the accelerometer
    quit();
}

@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {

}

private void quit(){
    mSensorManager.unregisterListener(MyService.this);
    wakeLock.release();
    this.stopSelf();
}
}

And I keep on getting the toasts from my MyService class telling me that my onCreate and onStart were successfully instantiated, even after calling my cancelAlarm method.

Do you have the broadcast receiver registered in the android manifest? — Andrew El-Masry, Jul 27 '17 at 20:30
Why are you using `ALARM_ID` on creation, and `alarmId` on cancel? — Daniel Nugent, Jul 27 '17 at 20:33
@AndrewEl-Masry yes, I have my `AlarmReciever` class registered in my manifest — cjnash, Jul 28 '17 at 12:42
@DanielNugent they are actually the same thing, I just pass `ALARM_ID` to `alarmId` in `cancelAlarm(int alarmId)` — cjnash, Jul 28 '17 at 12:43

Ferdous Ahamed · Accepted Answer · 2017-07-28T15:08:13.930

1

Use same PendingIntent that you used while creating Alarm. Use AlarmReceiver.class instead of AlarmManager.class in your Intent:

Intent i = new Intent(getBaseContext(), AlarmReceiver.class);

Update cancelAlarm() method as below:

private void cancelAlarm(int alarmId){
    Intent i = new Intent(getBaseContext(), AlarmReceiver.class);
    PendingIntent sender = PendingIntent.getBroadcast(MainActivity.this, alarmId, i, PendingIntent.FLAG_UPDATE_CURRENT);

    AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    alarmManager.cancel(sender);
    sender.cancel();
}

Hope this will help~

edited Jul 28 '17 at 15:08

answered Jul 27 '17 at 20:38

Ferdous Ahamed

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is adding the `PendingIntent.FLAG_UPDATE_CURRENT` the only change here? If so I just tested it and it has no effect. – cjnash Jul 28 '17 at 12:42
No, Use `AlarmReceiver.class` instead of `AlarmManager.class` in your Intent >> `Intent i = new Intent(getBaseContext(), AlarmReceiver.class);` – Ferdous Ahamed Jul 28 '17 at 14:12

cancelAlarm method not actually canceling my AlarmManager

1 Answers1