You must reset alerts. Android OS does not support your warnings on reboot, up to your application. Create a BroadcastReceiver (I named my BootReceiver in my example below) to handle the android.intent.action.BOOT_COMPLETED action (this is defined in the manifest). With BroadcastReceiver, you can restart all your alerts. Do not forget to add permission "android.permission.RECEIVE_BOOT_COMPLETED".
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" /> ... <receiver android:name=".BootReceiver"> <intent-filter> <action android:name="android.intent.action.BOOT_COMPLETED" /> </intent-filter> </receiver>
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