How do I replace AsyncTask with RxJava in Room methods?

Question

I have an insert method that uses Asynctask to set a new item in the Room database. Can I get rid of the InsertContactAsyncTask class and switch to using RxJava? I can't find such examples on the Internet

method insert:

override fun insert(contact: Contact) {
        InsertContactAsyncTask().execute(contact)
}

AsyncTask class:

class InsertContactAsyncTask: AsyncTask<Contact, Unit, Unit>() {

        private val contactDao: ContactDao? = null

        override fun doInBackground(vararg param: Contact) {
            contactDao?.insert(param[0])
        }
}

Answer 1

fun insert(contact:Contact) : Completable

Then somewhere you call this method

contactDao.insert()
.subscribeOn(Schedulers.IO)
.observeOn(AndroidSchedulers.Main)
.subscribe{Log.d("test","insertcompleted")
//do something when insert completed
}

or just place insert into completable like this

fun insertCompletable(contact:Contact){
Completable.fromAction{contactDao.insert}
}

and subscribe to it the same way as previous