我在 android studio 的 Textview 中显示货币汇率时遇到问题

我无法在文本视图中显示货币汇率我想显示货币汇率然后我必须计算其在沙特里亚尔和阿拉伯酋长国达勒姆的价值我只使用 11 种货币

我从 3 天开始解决它，但它没有以任何方式工作

   import android.app.ProgressDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.VolleyLog;
import com.android.volley.toolbox.JsonObjectRequest;

import org.json.JSONException;
import org.json.JSONObject;

import java.util.Currency;


public class currencconvert extends AppCompatActivity implements AdapterView.OnItemSelectedListener{

    private static final String TAG = "tag";
    //Url
    //this Prayer Timings is only for london now

    // Tag used to cancel the request
    String tag_json_obj = "json_obj_req";

    //progress Dialog
    ProgressDialog pDialog;

    TextView usdtxt, eurtxt, inrtxt, pkrtxt, afntxt, bdttxt, idrtxt, myrtxt, trytxt, aedtxt, sartxt;
    EditText addnum;
    Button cnvrtbtn;



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_currencconvert);

        usdtxt      =  findViewById(R.id.usd);
        eurtxt      =  findViewById(R.id.euro);
        inrtxt     =   findViewById(R.id.inr);
        pkrtxt     = findViewById(R.id.pkr);
        afntxt   =     findViewById(R.id.afn);
        bdttxt      =  findViewById(R.id.bdt);
        idrtxt      =  findViewById(R.id.idr);
        myrtxt      =  findViewById(R.id.myr);
        trytxt      =  findViewById(R.id.tury);
        aedtxt      =  findViewById(R.id.aed);
        sartxt      =  findViewById(R.id.sar);

       Spinner spinner = (Spinner) findViewById(R.id.spin);
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.currency, android.R.layout.simple_gallery_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(this);

       // link wagera he ye


        // function to get location
        Currencconvert();

    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        String text = parent.getItemAtPosition(position).toString();
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {

    }



    public void Currencconvert() {

        pDialog = new ProgressDialog(this);
        pDialog.setMessage("Loading...");
        pDialog.show();



        String Url  = "http://data.fixer.io/api/latest?access_key=9ec08275542de6b1646a986ffe785667";


        JsonObjectRequest request = new JsonObjectRequest(Request.Method.GET, Url, null,
                new Response.Listener<JSONObject>() {

                    @Override
                    public void onResponse(JSONObject response) {
                        try {

                            Toast.makeText(currencconvert.this, "your code run", Toast.LENGTH_SHORT).show();

                            // get date

                           //String date = response.getJSONArray("JSON").getJSONObject(0).get("date").toString();


                            // for getting namaz timings
                            String usdtx = response.getJSONArray("rates").getJSONObject(0).get("USD").toString();
                            String eurtx = response.getJSONArray("rates").getJSONObject(0).get("EUR").toString();
                            int inrtx =  Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("INR").toString());
                            int pkrtx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("PKR").toString());
                            int afntx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("AFN").toString());
                            int bdttx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("BDT").toString());
                            int idrtx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("IDR").toString());
                            int myrtx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("MYR").toString());
                            int trytx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("TRY").toString());
                            int aedtx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("AED").toString());
                            int sartx = Integer.parseInt(response.getJSONArray("rates").getJSONObject(0).get("SAR").toString());

                            Toast.makeText(currencconvert.this, "your code in  the middle", Toast.LENGTH_SHORT).show();

                            usdtxt.setText(usdtx);
                            eurtxt.setText(eurtx);
                            inrtxt.setText(inrtx);
                            pkrtxt.setText(pkrtx);
                            afntxt.setText(afntx);
                            bdttxt.setText(bdttx);
                            idrtxt.setText(idrtx);
                            myrtxt.setText(myrtx);
                            trytxt.setText(trytx);
                            aedtxt.setText(aedtx);
                            sartxt.setText(sartx);


                            Toast.makeText(currencconvert.this, "congrats your code run completend", Toast.LENGTH_SHORT).show();


                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                        pDialog.hide();
                    }
                }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                VolleyLog.d(TAG, "Error: " + error.getMessage());
                Toast.makeText(currencconvert.this, "Error", Toast.LENGTH_SHORT).show();

                pDialog.hide();
            }
        });

// Adding request to request queue
        AppController.getInstance().addToRequestQueue(request, tag_json_obj);

    }
}