I did implemented the ArrayAdapter, but i wanted a more flexible way of doing this..
now i’ve updated my code for RecyclerView but it doesn’t display anything!
I followed a tutorial from start to finish.
My code compiles.

Here is the code of my Adapter:

package com.gunsailor.myapplication.fragments

import android.annotation.SuppressLint
import android.content.Context
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Filter
import android.widget.Filterable
import android.widget.TextView
import androidx.fragment.app.Fragment
import androidx.lifecycle.ViewModelProvider
import androidx.navigation.fragment.NavHostFragment.Companion.findNavController
import androidx.recyclerview.widget.RecyclerView
import com.gunsailor.myapplication.R

class CityAdapterView(val context: Context, var cities: ArrayList<City>, val fragment: Fragment) : RecyclerView.Adapter<CityAdapterView.Holder>(), Filterable {

    val buffer = ArrayList(cities)
    inner class Holder(itemView: View): RecyclerView.ViewHolder(itemView), View.OnClickListener
    {
        val itemName: TextView
        val itemLongitude: TextView
        val itemLatitude: TextView
        init {
            itemName = itemView.findViewById<TextView>(R.id.itemName)

            itemLongitude= itemView.findViewById<TextView>(R.id.itemLongitude)

            itemLatitude= itemView.findViewById<TextView>(R.id.itemLatitude)
        }

        override fun onClick(v: View?) {

            val model = ViewModelProvider(fragment.requireActivity()).get(SharedViewModel::class.java)
            model.modifyCoordinatesLocation(cities.get(position).longitude, cities.get(position).latitude)
            findNavController(fragment).navigate(R.id.toPostel)
        }
    }

    override fun getFilter(): Filter {
        return object : Filter() {
            override fun publishResults(charSequence: CharSequence?, filterResults: FilterResults) {
                if (filterResults.count > 0) {
                    cities.clear()
                    cities.addAll(filterResults.values as ArrayList<City>)
                    notifyDataSetChanged()
                }
            }

            override fun performFiltering(search: CharSequence): FilterResults {
                val queryString = search.toString().lowercase()
                val list = ArrayList(buffer)
                val filterResults = FilterResults()
                if (queryString.isEmpty()) {
                    filterResults.values = list
                    filterResults.count = list.size
                }else {
                    val listFiltered = list.filter {
                        it.name.lowercase().contains(queryString)
                    }
                    filterResults.values = listFiltered
                    filterResults.count = listFiltered.size
                }
                return filterResults
            }
        }
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CityAdapterView.Holder {

        val view = LayoutInflater.from(context).inflate(R.layout.list_view_items, parent, false)

        return Holder(view)
    }

    override fun getItemCount(): Int {
        return cities.size
    }

    @SuppressLint("SetTextI18n")
    override fun onBindViewHolder(holder: CityAdapterView.Holder, position: Int) {

        holder.itemLatitude.setText("latitude :" + cities.get(position).latitude.toString())
        holder.itemLongitude.setText("longitude :" + cities.get(position).longitude.toString())
        holder.itemName.setText(cities.get(position).name)
    }
}

And here is the code of my fragment:

package com.gunsailor.myapplication.fragments

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.SearchView
import androidx.fragment.app.Fragment
import androidx.recyclerview.widget.RecyclerView
import com.gunsailor.myapplication.R
import com.gunsailor.myapplication.Utils.StarsUtils


class LocationList : Fragment() {

    lateinit var locations: RecyclerView

    lateinit var listAdapter: CityAdapterView

    lateinit var searchView: SearchView

    lateinit var locationList: StarsUtils

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
    }

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

        val viewLayout = inflater.inflate(R.layout.fragment_location_list, container, false)
        locations = viewLayout.findViewById(R.id.locations)
        searchView = viewLayout.findViewById(R.id.searchView)

        locationList = StarsUtils(requireContext(), "France.json")
        locationList.parse()
        locationList.JSON2Object()

        listAdapter = CityAdapterView(
            requireContext(),
            locationList.cities, this
        )

        locations.adapter = listAdapter

        searchView.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
            override fun onQueryTextSubmit(query: String?): Boolean {
                if (query != null) {
                    listAdapter.getFilter().filter(query)
                }
                return false
            }

            override fun onQueryTextChange(newText: String?): Boolean {
                listAdapter.filter.filter(newText)
                return false
            }
        })

        return viewLayout
    }
}

I don’t understand what i miss…
Thanks a lot!

I’ve followed a tutorial from start to finish…
And i wear my glasses!