call retrofit for all visible items in recyclerview

Question

Using room and paging library with MVVM. What i am trying to achieve is to call retrofit to get some data for every visible item in recycler view and then update the view accordingly. For now what i have achieved is to just implement the paging library and show data accordingly.

What i can do is to get the pagedlist and get data for whole list and update the view Or i can call api for every list item. We don't want the user to wait a lot to see the updated data on the visible item

class AllPetsFragment : Fragment() {

private lateinit var binding : FragmentAllPetsfragmentBinding
private lateinit var linearLayoutManager: LinearLayoutManager
private lateinit var allPetsViewModel: MainActivityViewModel

override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
): View {

    binding = FragmentAllPetsfragmentBinding.inflate(inflater, container, false)
    val view : View = binding.root

    allPetsViewModel = ViewModelProvider(requireActivity()).get(MainActivityViewModel::class.java)

    binding.btnOpenAddPet.setOnClickListener{
        startActivity(Intent(activity, AddPetActivity::class.java))
    }

    val adapter = PetAdapter(requireContext(), ClickListener {
        allPetsViewModel.updateData(it)
        val action = AllPetsFragmentDirections.actionMainMap()
        Navigation.findNavController(view).navigate(action)
    })
    linearLayoutManager = LinearLayoutManager(requireContext())
    binding.petsRecycler.layoutManager = linearLayoutManager
    binding.petsRecycler.adapter = adapter

    subscribeUi(adapter)

    return view
}



private fun subscribeUi(adapter: PetAdapter) {
    allPetsViewModel.getDevicesLiveData().observe(viewLifecycleOwner, { names ->
        if (names != null){
            adapter.submitList(names)
        }

    })


}

}

class PetAdapter(val context: Context, private val cl: ClickListener) :
    PagedListAdapter<Device, PetAdapter.PetViewHolder>(PersonDiffCallback()) {


override fun onBindViewHolder(holder: PetViewHolder, position: Int) {
    val device = getItem(position)

    if (device == null) {
        holder.clear()
    } else {
        holder.bind(device, cl.clickListener)
    }
}

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PetViewHolder {
    return PetViewHolder(LayoutInflater.from(context).inflate(R.layout.item_pet,
            parent, false))
}

class PetViewHolder(view: View) : RecyclerView.ViewHolder(view) {

    var tvName: TextView = view.findViewById(R.id.petName)
    var tvDistance: TextView = view.findViewById(R.id.totalDistance)
    var txtBattery: TextView = view.findViewById(R.id.txtBattery)
    var txtGeofence: TextView = view.findViewById(R.id.txtGeofence)


    fun bind(device: Device, clickListener: (Device) -> Unit) {
        tvName.text = device.name

        itemView.setOnClickListener { clickListener(device) }
    }

    fun clear() {
        tvName.text = null
    }
}

override fun getCurrentList(): PagedList<Device>? {
    return super.getCurrentList()
}

override fun onCurrentListChanged(currentList: PagedList<Device>?) {
    Log.d("ListSize", currentList?.size.toString())
    super.onCurrentListChanged(currentList)
}

}

class PersonDiffCallback : DiffUtil.ItemCallback<Device>() {

override fun areItemsTheSame(oldItem: Device, newItem: Device): Boolean {
    return oldItem.id == newItem.id
}

override fun areContentsTheSame(oldItem: Device, newItem: Device): Boolean {
    return oldItem == newItem;
}

}