private Spinner spinner;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_training_layout, container, false);
    spinner = (Spinner) view.findViewById(R.id.spinnerTrainers);
…

   private class ConnectMySql extends AsyncTask<String, Void, String> {
        List<String> trainers = new ArrayList<String>();
        ArrayAdapter<String> adapter;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected String doInBackground(String... params) {
            try {
                Class.forName("com.mysql.jdbc.Driver");
                Connection con = DriverManager.getConnection(url, user, pass);

                Statement st = con.createStatement();
                ResultSet rs = st.executeQuery("SELECT * FROM pdc_production.die_detail");
                ResultSetMetaData rsmd = rs.getMetaData();

                while (rs.next()) {
                    trainers.add(rs.getString(1).toString() + ":" + rs.getString(2).toString());
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return "";
        }

        @Override
        protected void onPostExecute(String result) {
            adapter = new ArrayAdapter<String> (getContext(), android.R.layout.simple_spinner_dropdown_item, trainers);
//            adapter = ArrayAdapter.createFromResource(getContext(), trainers, android.R.layout.simple_spinner_dropdown_item);
            spinner.setAdapter(adapter);
        }

    }

adapter = new ArrayAdapter<String> (getContext(), android.R.layout.simple_spinner_dropdown_item, trainers)

adapter = ArrayAdapter.createFromResource(getContext(), trainers, android.R.layout.simple_spinner_dropdown_item)

class PhotoFragment : Fragment() {

    companion object {
        fun newInstance() = PhotoFragment()
    }

    @Inject
    lateinit var dataManager: DataManager

    private lateinit var viewModel: PhotoViewModel

    var searchList: MutableList<String> = ArrayList()

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?
    ): View? {
        val view = inflater.inflate(R.layout.photo_fragment, container, false)

        (activity as AppCompatActivity).supportActionBar
        view.toolbarProfileSearch.setNavigationOnClickListener { context }
        setHasOptionsMenu(true)

        return view

    }

    override fun onActivityCreated(savedInstanceState: Bundle?) {
        super.onActivityCreated(savedInstanceState)
        componentFragment.inject(this)
        viewModel = ViewModelProviders.of(this, PhotoFragmentFactory(dataManager)).get(PhotoViewModel::class.java)
        setHasOptionsMenu(true)


        viewModel.profileResult.observe(this, Observer { profileResult ->
            loadPicture(profileResult)
        })


        btnGetProfilePicture.setOnClickListener {
            viewModel.callProfileResult(editUserName.text.toString())
        }


    }

    override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {

        inflater.inflate(R.menu.toolbar_menu_searchprofile, menu)
        val searchItem = menu.findItem(R.id.search)
        val searchView = searchItem.actionView as SearchView

        searchView.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
            override fun onQueryTextSubmit(query: String?): Boolean {
                searchView.clearFocus()
                searchView.setQuery("", false)
                searchItem.collapseActionView()
                Log.d("SEARCH1", "$query")

                return true

            }

            override fun onQueryTextChange(newText: String?): Boolean {
                Log.d("SEARCH2", "$newText")
                return false

            }
        })


        super.onCreateOptionsMenu(menu, inflater)
    }
}