问题
I have a foreground monitoring class that registers as a LifecycleObserver to the ProcessLifecycleOwner's Lifecycle. When I receive an ON_START event, I am starting a Service to run while the app is in the foreground. I am seeing IllegalStateExceptions every so often on app launch stating that starting a service in the background is not allowed. Is this not a reliable way to check if the app is in the foreground? I thought ProcessLifecycleOwner was suppose to be the answer to the old, hacky way of counting activities with Application.ActivityLifecycleCallbacks. I didn't have this problem using that solution.
来源：https://stackoverflow.com/questions/55263146/crash-starting-service-when-observing-processlifecycleowner-on-start