Protected method can not be overrided by Subclass in Kotlin.

[ShawnXiaFei]

First, thanks for what you have done.
And then, there has a bug in CallRecordReceiver.kt. See the code below:

// Derived classes could override these to respond to specific events of interest
protected fun onRecordingStarted(context: Context, callRecord: CallRecord, audioFile: File?) {}

protected fun onRecordingFinished(context: Context, callRecord: CallRecord, audioFile: File?) {}

But, in Kotlin, they can not be overrided by subclass, you need to add open after protected.
I have forked you project and fix it, you can check it ShawnXiaFei/CallRecorder

Thanks again.

[aykuttasil]

Thank you. Actually, you can make PR for this subject?