Alarm in Android-Scheduling Timed Tasks Using AlarmManager in Android.pdf

In Android, alarms are used to perform scheduled operations at specific times, even if the application is not currently running. The primary component used to trigger alarms is the AlarmManager class, which allows developers to schedule their app to run at a particular time or interval. Alarms are commonly used for tasks such as setting reminders, sending notifications, syncing data, or starting background services. One of the key features of AlarmManager is its ability to wake up the device using the RTC_WAKEUP type, which is especially useful for time-sensitive operations. There are different types of alarms: RTC (Real Time Clock): Triggers based on the current wall clock time. RTC_WAKEUP: Same as RTC, but wakes the device if it's asleep. ELAPSED_REALTIME: Triggers after a specific time has elapsed since boot. ELAPSED_REALTIME_WAKEUP: Same as above but wakes the device if needed. To set an alarm, you typically create a PendingIntent that defines the action to perform (like broadcasting an intent or starting a service), and then schedule it using AlarmManager.set() or AlarmManager.setRepeating() for repeating alarms. From Android 6.0 (API level 23) onwards, doze mode and battery optimizations can delay alarms, so for precise timing, developers can use setExact() or setExactAndAllowWhileIdle(). It's important to use alarms wisely to conserve battery life. For repeating tasks that are not time-critical, consider using WorkManager instead, which is better suited for background processing in modern Android development. Overall, Android alarms are a powerful way to schedule operations, but developers should choose the right type of alarm based on the timing accuracy and power requirements of their task.