AlarmManager not working?

Question

Android

The essence of the problem is that when the notification time is set, there is no notification at this time ....
There is a code here stackoverflow.com/questions/33221084/dont-work-ala...
The notification itself, if used without AlarmManager, works but does not work with it at the specified time wants .... There are no errors, just no notification itself

Answer 1

1) With Kitkat, to start alarm at exactly the specified hour, you need to use the setExact() method instead of set()
2) With Marshmallow, you need to use setExactAndAllowWhileIdle()
for this purpose 3) If the device is asleep, then alarm will not work with the RTC flag. To do this, use the RTC_WAKEUP
flag I recommend reading:
developer.android.com/training/scheduling/alarms.html
developer.android.com/training/monitoring-device-s...
developer.android.com/reference/android/app/ AlarmM...