How to get a spinner on android using volley to store data in mysql database?

I'm trying to get a spinner on Android using volley to store Gender data into a mySQL database.
 here's the source code

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.example.carldwalters.communications.create_account"
    tools:showIn="@layout/activity_create_account">

    <ScrollView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/scrollView"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true">



    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentBottom="true"
        android:layout_alignParentStart="true">


        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="First name"
            android:id="@+id/first_nameTextView"
            android:layout_alignParentTop="true"
            android:layout_marginBottom="1900dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text=""
            android:ems="10"
            android:id="@+id/first_nameEditText"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="33dp" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Middle name"
            android:id="@+id/middleNameTextTiew"
            android:layout_below="@+id/first_nameEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="33dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text=""
            android:ems="10"
            android:id="@+id/middle_nameEditText"
            android:layout_below="@+id/middleNameTextTiew"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Last name"
            android:id="@+id/lastNameTextView"
            android:layout_below="@+id/middle_nameEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="36dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text=""
            android:ems="10"
            android:id="@+id/last_nameEditText"
            android:layout_below="@+id/lastNameTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="E-mail"
            android:id="@+id/e_mailTextView"
            android:layout_below="@+id/last_nameEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="36dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textEmailAddress"
            android:ems="10"
            android:id="@+id/e_mailEditText"
            android:layout_below="@+id/e_mailTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="User name"
            android:id="@+id/user_nameTextView"
            android:layout_below="@+id/e_mailEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="40dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/user_nameEditText"
            android:layout_below="@+id/user_nameTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Date of birth"
            android:id="@+id/dateOfBirthTextView"
            android:layout_below="@+id/user_nameEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="40dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/date_of_birthEditText"
            android:layout_below="@+id/dateOfBirthTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Gender"
            android:layout_marginTop="629dp"
            android:id="@+id/genderTextView" />



        <Spinner
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/genderSpinner"
            android:layout_marginTop="660dp"
            android:layout_centerHorizontal="true" />


        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/genderEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="740dp" />











        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Password"
            android:id="@+id/passwordTextView"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="900dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPassword"
            android:ems="10"
            android:id="@+id/passwordEditText"
            android:layout_below="@+id/passwordTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="Confirm password"
            android:id="@+id/confirmPasswordTextView"
            android:layout_below="@+id/passwordEditText"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="20dp" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPassword"
            android:ems="10"
            android:id="@+id/confirm_passwordEditText"
            android:layout_below="@+id/confirmPasswordTextView"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:text="By clicking submit you agree to the terms and services and private policy."
            android:id="@+id/legalTextView"
            android:layout_marginTop="1600dp"
            android:layout_alignParentStart="true" />

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Terms and conditions"
            android:id="@+id/terms_and_conditionsButton"
            android:layout_marginTop="1701dp"
            android:layout_alignParentStart="true" />

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Private policy"
            android:id="@+id/private_policyButton"
            android:layout_alignParentStart="true"
            android:layout_marginTop="1750dp" />

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Submit"
            android:id="@+id/SubmitButton"
            android:layout_alignParentStart="true"
            android:layout_marginTop="1800dp" />




    </RelativeLayout>
    </ScrollView>
</RelativeLayout>

package com.example.carldwalters.communications;

import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;

import android.app.AlertDialog;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.toolbox.Volley;

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

import java.util.ArrayList;

import static android.R.layout.simple_spinner_item;


public abstract class create_account  extends AppCompatActivity implements View.OnClickListener, AdapterView.OnItemSelectedListener{

   // EditText genderEditText;
    ArrayAdapter<CharSequence> adapter;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_create_account);
        //Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        // setSupportActionBar(toolbar);
        //  showDialogOnButtonClick();


        final EditText first_nameEditText = (EditText) findViewById(R.id.first_nameEditText);
        final EditText middle_nameEditText = (EditText) findViewById(R.id.middle_nameEditText);
        final EditText last_nameEditText = (EditText) findViewById(R.id.last_nameEditText);
        final EditText e_mailEditText = (EditText) findViewById(R.id.e_mailEditText);
        final EditText user_nameEditText = (EditText) findViewById(R.id.user_nameEditText);
        final EditText date_of_birthEditText = (EditText) findViewById(R.id.date_of_birthEditText);
        final Spinner genderSpinner = (Spinner) findViewById(R.id.genderSpinner);
        // final EditText genderEditText = (EditText) findViewById(R.id.genderEditText);
        final EditText passwordEditText = (EditText) findViewById(R.id.passwordEditText);
        final EditText confirm_passwordEditText = (EditText) findViewById(R.id.confirm_passwordEditText);
        final Button terms_and_conditionsButton = (Button) findViewById(R.id.terms_and_conditionsButton);
        final Button private_policyButton = (Button) findViewById(R.id.private_policyButton);
        final Button SubmitButton = (Button) findViewById(R.id.SubmitButton);

        terms_and_conditionsButton.setOnClickListener(this);
        private_policyButton.setOnClickListener(this);
        //  ArrayAdapter adapter=ArrayAdapter.createFromResource(this,R.array.gender,android.R.layout.simple_spinner_item);
        //  genderSpinner.setAdapter(adapter);
        //  genderSpinner.setOnItemSelectedListener(this);
        // SubmitButton.setOnClickListener(this);
        // String gender = genderSpinner.getSelectedItem().toString();

        //   ArrayAdapter adapter = ArrayAdapter.createFromResource(this, R.array.genderSpinner, android.R.layout.simple_spinner_item);
        //   Gender.setAdapter(adapter);

        SubmitButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                final String first_name = first_nameEditText.getText().toString();
                final String middle_name = middle_nameEditText.getText().toString();
                final String last_name = last_nameEditText.getText().toString();
                final String e_mail = e_mailEditText.getText().toString();
                final String user_name = user_nameEditText.getText().toString();
                final String date_of_birth = date_of_birthEditText.getText().toString();
                final String gender = genderSpinner.getSelectedItem().toString();
                final String password = passwordEditText.getText().toString();
                final String confirm_password = confirm_passwordEditText.getText().toString();


                Response.Listener<String> responseListener = new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject jsonResponse = new JSONObject(response);
                            boolean success = jsonResponse.getBoolean("success");
                            if (success) {
                                Intent intent = new Intent(create_account.this, login.class);
                                create_account.this.startActivity(intent);
                            } else {
                                AlertDialog.Builder builder = new AlertDialog.Builder(create_account.this);
                                builder.setMessage("Register Failed")
                                        .setNegativeButton("Retry", null)
                                        .create()
                                        .show();
                            }
                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                };

                RegisterRequest registerRequest = new RegisterRequest(first_name, middle_name, last_name, e_mail, user_name, date_of_birth, gender, password, confirm_password, responseListener);
                RequestQueue queue = Volley.newRequestQueue(create_account.this);
                queue.add(registerRequest);
            }
        });
    }

    @Override
    public void onClick(View v) {




        switch (v.getId()) {
            case R.id.terms_and_conditionsButton:
                break;
            case R.id.private_policyButton:
                break;
            //     case R.id.SubmitButton:


            //        String firstName = first_nameEditText.getText().toString();
            //        String middleName = middle_nameEditText.getText().toString();
            //        String lastName = last_nameEditText.getText().toString();
            //        String Email = e_mailEditText.getText().toString();
            //        String userName = user_nameEditText.getText().toString();
            //        String dateOfBirth = date_of_birthEditText.getText().toString();
            //        String Gender = genderSpinner.getSelectedItem().toString();
            //        String Password = passwordEditText.getText().toString();
            //        String confirmPassword = confirm_passwordEditText.getText().toString();
            //        String method = "register";
            //        BackgroundTask backgroundTask = new BackgroundTask(this);
            //        backgroundTask.execute(method,firstName,middleName,lastName,Email,userName,dateOfBirth,Gender,Password,confirmPassword);


            //                User user = new User(first_name, middle_name, last_name, e_mail, user_name, date_of_birth,
            //                    gender, password, confirm_password);


        }


             }



    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }






            //  public void onStart(){
            //      super.onStart();

            //     EditText new_date_of_birthEditText=(EditText)findViewById(R.id.new_date_of_birthEditText);
            //      new_date_of_birthEditText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
            //          public void onFocusChange(View view, boolean hasfocus) {
            //              if (hasfocus) {
            //                   DateOfBirthPicker dialog = new DateOfBirthPicker(view);
            //                   FragmentTransaction ft = getFragmentManager().beginTransaction();
            //                   dialog.show(ft, "DatePicker");
            //               }
            //           }
            //       });
            //   }

};

package com.example.carldwalters.communications;

import android.widget.RadioButton;

import com.android.volley.Response;
import com.android.volley.toolbox.StringRequest;

import java.util.HashMap;
import java.util.Map;

/**
 * Created by Carl on 5/10/2016.
 */
public class RegisterRequest extends StringRequest {
    private static final String REGISTER_REQUEST_URL = "http://127.0.0.1/register.php";
    private Map<String, String> params;

    public RegisterRequest(String first_name, String middle_name, String last_name, String e_mail, String user_name, String date_of_birth, String gender, String password, String confirm_password, Response.Listener<String> listener) {
        super(Method.POST, REGISTER_REQUEST_URL, listener, null);
        params = new HashMap<>();
        params.put("first_name", first_name);
        params.put("middle_name", middle_name);
        params.put("last_name", last_name);
        params.put("e_mail", e_mail);
        params.put("user_name", user_name);
        params.put("date_of_birth", date_of_birth);
        params.put("gender", gender);
        params.put("password", password);
        params.put("confirm_password", confirm_password);

    }



    @Override
    public Map<String, String> getParams() {

        return params;
    }
}