Does AlarmManager.setExact () start at the wrong time?

Question

I plan that pendingIntent is dispatched in 5 seconds, but starts in 23 seconds. API = 19 (AlarmManager.setExact (...)):

10-23 16:43:44.638 11903-11903/? D/MainActivity﹕ Fri Oct 23 16:43:44 GMT+05:00 2015: scheduled in 5000 ms 10-23 16:44:07.728 11903-11903/? D/MainActivity﹕ Fri Oct 23 16:44:07 GMT+05:00 2015: fired private PendingIntent pendingIntent; private int SCHEDULE_REQUEST_CODE = 1; private static final String SCHEDULER_ACTION = "android.intent.action.FOTA_SCHEDULE_CHECK"; private void log(String message) { StringBuilder sb = new StringBuilder(); sb.append(new Date().toString()); sb.append(": "); sb.append(message); sb.append("\n"); Log.d(getClass().getSimpleName(), sb.toString()); tv.append(sb.toString()); tv.append("\n"); } private BroadcastReceiver schedulerReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { log("fired"); } }; private void schedule() { registerReceiver(schedulerReceiver, new IntentFilter(SCHEDULER_ACTION)); Intent scheduleIntent = new Intent(SCHEDULER_ACTION); pendingIntent = PendingIntent.getBroadcast(this, SCHEDULE_REQUEST_CODE, scheduleIntent, 0); AlarmManager alarmManager = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE); // first invocation (once, exact) int delay = 5 * 1000; // 5s log("scheduled in " + delay + " ms"); alarmManager.setExact(AlarmManager.RTC, System.currentTimeMillis() + delay, pendingIntent); } @Override protected void onDestroy() { super.onDestroy(); unschedule(); } private void unschedule() { AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE); alarmManager.cancel(pendingIntent); pendingIntent = null; unregisterReceiver(schedulerReceiver); } 

Answer 1

I have the same problem, but pendingIntent starts after 5 seconds, not 2, as I try to install.

 alarmManager.setExact(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 2 * 1000, pIntent); 

If I set 5 seconds or more, alarmManager starts exactly. I don’t know what time span I will get in the working environment, so I choose 1 minute as a short time span.

So my application used postDelayed() instead of alarmManager for short time intervals and alarmManager for long time.

Code example:

 if (delay == 0) { Intent intent = new Intent(context, SoundService.class); intent.putExtra(SoundService.SOUND, sound); context.startService(intent); } else if (delay <= 60) { (new Handler()).postDelayed(new Runnable() { @Override public void run() { Intent intent = new Intent(context, SoundService.class); intent.putExtra(SoundService.SOUND, sound); context.startService(intent); } }, delay * 1000); } else if (delay > 60) { final int SDK_INT = Build.VERSION.SDK_INT; Intent intent = new Intent(context, AlarmBroadcastReceiver.class); intent.setAction("action_play: " + sound); intent.putExtra(SoundService.SOUND, sound); PendingIntent pIntent = PendingIntent.getBroadcast(context, 0, intent, 0); AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); long runTime = System.currentTimeMillis() + delay * 1000; if (SDK_INT < Build.VERSION_CODES.KITKAT) { alarmManager.set(AlarmManager.RTC_WAKEUP, runTime, pIntent); } else if ((SDK_INT >= Build.VERSION_CODES.KITKAT) && (SDK_INT < Build.VERSION_CODES.M)) { alarmManager.setExact(AlarmManager.RTC_WAKEUP, runTime, pIntent); } else if (SDK_INT >= Build.VERSION_CODES.M) { alarmManager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, runTime, pIntent); } } 

Where SoundService - Service with sound functions, delay - delay before playback, in seconds, AlarmBroadcastReceiver -

 public class AlarmBroadcastReceiver extends BroadcastReceiver { final String LOG_TAG = this.getClass().getName(); @Override public void onReceive(Context ctx, Intent intent) { if (intent.getAction().startsWith("action_play:")){ Intent playIntent = new Intent(ctx, SoundService.class); playIntent.putExtra(SoundService.SOUND, intent.getStringExtra(SoundService.SOUND)); ctx.startService(playIntent); } } 

}