Background operation of BLE Library with Android 8 - Howto?

Question

I have extended the Template app in nRF Toolbox. When my app runs in the background on an Android 8 (only) device and I try to connect to the peripheral, I get this error when trying to execute startService(service) in BleProfileServiceReadyActivity: 
 java.lang.IllegalStateException: Not allowed to start service Intent { ... }: app is in background 
 This is expected as pointed out here and elsewhere: https://stackoverflow.com/questions/46445265/android-8-0-java-lang-illegalstateexception-not-allowed-to-start-service-inten What is Nordic's advice: Q1	On this topic in general? Q2	How should the Template app be changed to support BLE Library operation in the background? Q3	Is there a sample Android app (all versions) that will scan for BLE advertisments at all times (including when the app is in the background and/or the phone has been reset) and then spring into life, connect to the peripheral and interact with it? Q3 is what I am really trying to do. The Android Beacon Library addresses the problem, but is specific to beacons. IMHO this is a sufficiently important use case that it deserves a robust example from Nordic. Thanks

Aleksander Nowakowski · Answer

Hi, I remember answering to this question long time ago, but the answer must have get lost somewhere... Let's try again. 
 Since Android 8 there are restrictions in background services. A background service will be killed 5 min after the application was closed (went to background). Also, they may not be started using startService() when app is not in foreground. More here: https://developer.android.com/about/versions/oreo/background 
 The Template app keeps the service running only when the device is connected. I'd change the service to be a foreground service. 
 If you need to scan for a device in foreground, use new method in BluetoothLeScanner with IntentFilter instead of using service at all. 
 We don't have any example like you described, unfortunately. I agree that it is a good idea.

Background operation of BLE Library with Android 8 - Howto?

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