MainActivity.kt

    //Set mEventItemBook
    private val mBookAdapter: BookAdapter by lazy {
        BookAdapter().apply {
            mEventItemBook = { handleEventItemListBook(it) }
        }
    }
    
    //handleEvent
    private fun handleEventItemListBook(eventItemBook: EventItemBook) {
        Log.d("TODO", "event: $eventItemBook")
    }