Volley Library - Registration, Log-in, and Log-out

In this tutorial, we will create the basic user registration and log-in module using Volley library and JSON. Volley is a HTTP Library which provides the facilities for network connectivity for our app.

The advantages of using the Volley library are as follows:

Easier and faster request management.
Provide efficient network management.

For the server-side data handling, we are using the PHP with XAMPP server and MySQL for data manipulation.

Before creating the Android application module, let's first create the server-side data handling API code for registration and log-in in PHP and MySQL.

1. Create a database with the name registerlogin and table users which contains the following fields.

android Volley Library - Registration Log-in and Log-out

2. Write the following connection establishment code with PHP and database inside C:\xampp\htdocs\androidphpmysql directory.

In the androidphpmysql (your project location) directory, create a connection.php file and write the following code.

connection.php

<?php
$servername = "localhost";
$username = "root";
$password = "";
$database = "registerlogin";
$conn = new mysqli($servername, $username, $password, $database);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
?>

3. Create a registrationapi.php file in androidphpmysql directory and write the following code. This file handles the request coming from an Android application and generates a response in the form of JSON array to the android application.

registrationapi.php

<?php 
  require_once 'connection.php';
  $response = array();
  if(isset($_GET['apicall'])){
  switch($_GET['apicall']){
  case 'signup':
 	if(isTheseParametersAvailable(array('username','email','password','gender'))){
 	$username = $_POST['username']; 
 	$email = $_POST['email']; 
 	$password = md5($_POST['password']);
 	$gender = $_POST['gender']; 
 
 	$stmt = $conn->prepare("SELECT id FROM users WHERE username = ? OR email = ?");
 	$stmt->bind_param("ss", $username, $email);
 	$stmt->execute();
 	$stmt->store_result();
 
 	if($stmt->num_rows > 0){
 		$response['error'] = true;
 		$response['message'] = 'User already registered';
 		$stmt->close();
 	}
 	else{
 		$stmt = $conn->prepare("INSERT INTO users (username, email, password, gender) VALUES (?, ?, ?, ?)");
 		$stmt->bind_param("ssss", $username, $email, $password, $gender);
 
 		if($stmt->execute()){
 			$stmt = $conn->prepare("SELECT id, id, username, email, gender FROM users WHERE username = ?"); 
 			$stmt->bind_param("s",$username);
 			$stmt->execute();
 			$stmt->bind_result($userid, $id, $username, $email, $gender);
 			$stmt->fetch();
 
 			$user = array(
 			'id'=>$id, 
 			'username'=>$username, 
 			'email'=>$email,
 			'gender'=>$gender
 			);
 
 			$stmt->close();
 
 			$response['error'] = false; 
 			$response['message'] = 'User registered successfully'; 
 			$response['user'] = $user; 
 		}
 	}
 
}
else{
 	$response['error'] = true; 
 	$response['message'] = 'required parameters are not available'; 
}
break; 
case 'login':
  if(isTheseParametersAvailable(array('username', 'password'))){
 	$username = $_POST['username'];
  	$password = md5($_POST['password']); 
 
	$stmt = $conn->prepare("SELECT id, username, email, gender FROM users WHERE username = ? AND password = ?");
 	$stmt->bind_param("ss",$username, $password);
  	$stmt->execute();
 	$stmt->store_result();
 	if($stmt->num_rows > 0){
 	$stmt->bind_result($id, $username, $email, $gender);
 	$stmt->fetch();
 	$user = array(
 	'id'=>$id, 
 	'username'=>$username, 
 	'email'=>$email,
 	'gender'=>$gender
 	);
 
 	$response['error'] = false; 
 	$response['message'] = 'Login successfull'; 
 	$response['user'] = $user; 
 }
 else{
 	$response['error'] = false; 
 	$response['message'] = 'Invalid username or password';
 }
}
break; 
default: 
 $response['error'] = true; 
 $response['message'] = 'Invalid Operation Called';
}
}
else{
 $response['error'] = true; 
 $response['message'] = 'Invalid API Call';
}
echo json_encode($response);
function isTheseParametersAvailable($params){
foreach($params as $param){
 if(!isset($_POST[$param])){
	 return false; 
  }
}
return true; 
}
?>

To check your PHP API whether it is working fine or not, you can use the REST client such as Postman tool.

To check the registration code of API, you can pass the URL of registration with parameters.

Similarly, you can check the log-in action by passing log-in URL with valid parameters.

Now, in the Android application, we will create the three activity class for user registration, user log-in and display the user detail in main activity (as a profile).

Create an activity_main.xml in layout and add the below code. This activity is used for displaying the detail of the user as a profile.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context="example.javatpoint.com.volleyregistrationloginsystem.MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.0">

        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:text="Welcome to Profile"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

        <TableLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="50dp">


            <TableRow>

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="Id"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

                <TextView
                    android:id="@+id/textViewId"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="id"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />

            </TableRow>

            <TableRow>

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="Username"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

                <TextView
                    android:id="@+id/textViewUsername"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="username"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />

            </TableRow>

            <TableRow>

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="Email"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

                <TextView
                    android:id="@+id/textViewEmail"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="useremail"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />

            </TableRow>

            <TableRow>

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="Gender"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

                <TextView
                    android:id="@+id/textViewGender"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:text="gender"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />

            </TableRow>


        </TableLayout>

        <Button
            android:id="@+id/buttonLogout"
            android:layout_width="210dp"
            android:layout_height="50dp"
            android:layout_marginTop="150dp"
            android:layout_marginLeft="75dp"
            android:text="Logout" />
    </LinearLayout>

</android.support.constraint.ConstraintLayout>

Now, create an activity_login.xml file in layout directory with following code. This activity is used for user log-in UI.

activity_login.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context="example.javatpoint.com.volleyregistrationloginsystem.LoginActivity">

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="16dp"
        android:gravity="center"
        android:text="Login"
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/etUserName"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:ems="10"
        android:inputType="textPersonName"
        android:hint="user name"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.144" />

    <EditText
        android:id="@+id/etUserPassword"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:hint="password"
        android:ems="10"
        android:inputType="textPassword"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/etUserName" />

    <Button
        android:id="@+id/btnLogin"
        android:layout_width="210dp"
        android:layout_height="50dp"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:text="Login"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/etUserName"
        app:layout_constraintVertical_bias="0.754" />

    <TextView
        android:id="@+id/tvRegister"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:gravity="center"
        android:text="Create New Account\n Register Here"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/btnLogin"
        app:layout_constraintVertical_bias="0.405" />

    <ProgressBar
        android:id="@+id/progressBar"
        android:visibility="gone"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.456" />

</android.support.constraint.ConstraintLayout>

Create an activity_register.xml file in layout directory with following code. This activity is used for user registration UI.

activity_register.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context="example.javatpoint.com.volleyregistrationloginsystem.RegisterActivity">


    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="519dp"
        android:layout_centerVertical="true"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:orientation="vertical"
        android:padding="10dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.0">

        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Register"
            android:gravity="center"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

        <EditText
            android:id="@+id/editTextUsername"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="20dp"
            android:hint="Username"
            android:inputType="text" />

        <EditText
            android:id="@+id/editTextEmail"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="8dp"
            android:hint="Email"
            android:inputType="textEmailAddress" />

        <EditText
            android:id="@+id/editTextPassword"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="8dp"
            android:fontFamily="sans-serif"
            android:hint="Password"
            android:inputType="textPassword" />

        <RadioGroup
            android:id="@+id/radioGender"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="8dp"
            android:orientation="horizontal">

            <RadioButton
                android:id="@+id/radioButtonMale"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:checked="true"
                android:text="Male" />


            <RadioButton
                android:id="@+id/radioButtonFemale"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Female" />

        </RadioGroup>

        <Button
            android:id="@+id/buttonRegister"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="90dp"
            android:text="Register" />

        <TextView
            android:id="@+id/textViewLogin"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginTop="8dp"
            android:text="Already Registered?\nLogin Here"
            android:textAlignment="center"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />
    </LinearLayout>

    <ProgressBar
        android:visibility="gone"
        android:id="@+id/progressBar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true" />

</android.support.constraint.ConstraintLayout>

Add the volley library dependency in build.gradle file.

build.gradle

Create a data model class named as User.java with the following code.

User.java

package example.javatpoint.com.volleyregistrationloginsystem;


public class User {
    private int id;
    private String name, email, gender;

    public User(int id, String name, String email, String gender) {
        this.id = id;
        this.email = email;
        this.gender = gender;
        this.name = name;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }


    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }
}

We need to define our URL that call the API of server-side.

Create an URLs.java class and define the URL.

URLs.java

package example.javatpoint.com.volleyregistrationloginsystem;

public class URLs {
    private static final String ROOT_URL = "http://192.168.1.35/androidphpmysql/registrationapi.php?apicall=";
    public static final String URL_REGISTER = ROOT_URL + "signup";
    public static final String URL_LOGIN= ROOT_URL + "login";
}

VolleySingleton.java

package example.javatpoint.com.volleyregistrationloginsystem;

import android.content.Context;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.Volley;

public class VolleySingleton {
    private static VolleySingleton mInstance;
    private RequestQueue mRequestQueue;
    private static Context mCtx;

    private VolleySingleton(Context context) {
        mCtx = context;
        mRequestQueue = getRequestQueue();
    }

    public static synchronized VolleySingleton getInstance(Context context) {
        if (mInstance == null) {
            mInstance = new VolleySingleton(context);
        }
        return mInstance;
    }

    public RequestQueue getRequestQueue() {
        if (mRequestQueue == null) {
            // getApplicationContext() is key, it keeps you from leaking the
            // Activity or BroadcastReceiver if someone passes one in.
            mRequestQueue = Volley.newRequestQueue(mCtx.getApplicationContext());
        }
        return mRequestQueue;
    }

    public <T> void addToRequestQueue(Request<T> req) {
        getRequestQueue().add(req);
    }
}

Create a class named as SharedPreferences.java. In this class, we use the SharedPreferences class to store the user detail. The SharedPreferences class contains four methods with the following functionalities:

userLogin(): This method is used to store the user information in SharedPreferences after log-in.
isLoggedIn(): This method checks whether the user is already log-in or not.
getUser(): This method get the user information if log-in.
logout(): This method clear the SharedPreferences data and makes user log-out.

SharedPrefManager.java

package example.javatpoint.com.volleyregistrationloginsystem;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;

public class SharedPrefManager {

    private static final String SHARED_PREF_NAME = "volleyregisterlogin";
    private static final String KEY_USERNAME = "keyusername";
    private static final String KEY_EMAIL = "keyemail";
    private static final String KEY_GENDER = "keygender";
    private static final String KEY_ID = "keyid";
    private static SharedPrefManager mInstance;
    private static Context ctx;

    private SharedPrefManager(Context context) {
        ctx = context;
    }
    public static synchronized SharedPrefManager getInstance(Context context) {
        if (mInstance == null) {
            mInstance = new SharedPrefManager(context);
        }
        return mInstance;
    }

    //this method will store the user data in shared preferences
    public void userLogin(User user) {
        SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putInt(KEY_ID, user.getId());
        editor.putString(KEY_USERNAME, user.getName());
        editor.putString(KEY_EMAIL, user.getEmail());
        editor.putString(KEY_GENDER, user.getGender());
        editor.apply();
    }

    //this method will checker whether user is already logged in or not
    public boolean isLoggedIn() {
        SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        return sharedPreferences.getString(KEY_USERNAME, null) != null;
    }

    //this method will give the logged in user
    public User getUser() {
        SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        return new User(
                sharedPreferences.getInt(KEY_ID, -1),
                sharedPreferences.getString(KEY_USERNAME, null),
                sharedPreferences.getString(KEY_EMAIL, null),
                sharedPreferences.getString(KEY_GENDER, null)
        );
    }

    //this method will logout the user
    public void logout() {
        SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.clear();
        editor.apply();
        ctx.startActivity(new Intent(ctx, LoginActivity.class));
    }
}

Now, in the MainActivity.java class, we will display the user information if the user is log-in otherwise, it redirects to LoginActivity.java class. The onClick() method is used to log-out the user when clicking on the button.

MainActivity.java

package example.javatpoint.com.volleyregistrationloginsystem;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    TextView id,userName,userEmail,gender;
    Button btnLogout;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if(SharedPrefManager.getInstance(this).isLoggedIn()){
            id = findViewById(R.id.textViewId);
            userName = findViewById(R.id.textViewUsername);
            userEmail = findViewById(R.id.textViewEmail);
            gender = findViewById(R.id.textViewGender);
            btnLogout = findViewById(R.id.buttonLogout);
            User user = SharedPrefManager.getInstance(this).getUser();

            id.setText(String.valueOf(user.getId()));
            userEmail.setText(user.getEmail());
            gender.setText(user.getGender());
            userName.setText(user.getName());

            btnLogout.setOnClickListener(this);
        }
        else{
            Intent  intent = new Intent(MainActivity.this,LoginActivity.class);
            startActivity(intent);
            finish();
        }
    }
    public void onClick(View view){
        if(view.equals(btnLogout)){
            SharedPrefManager.getInstance(getApplicationContext()).logout();
        }
    }
}

In the LoginActivity.java class, we check if the user is already log-in or not, if true then redirect to MainActivity.java class otherwise, allow a user to log-in.

StringRequest class of Volley library is used for network module. The object of StringReuest class takes the parameters of the request method type, URL, and the response.

LoginActivity.java

package example.javatpoint.com.volleyregistrationloginsystem;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.HashMap;
import java.util.Map;

public class LoginActivity extends AppCompatActivity {
    EditText etName, etPassword;
    ProgressBar progressBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        if (SharedPrefManager.getInstance(this).isLoggedIn()) {
            finish();
            startActivity(new Intent(this, MainActivity.class));
        }

        progressBar = findViewById(R.id.progressBar);
        etName = findViewById(R.id.etUserName);
        etPassword = findViewById(R.id.etUserPassword);


        
        //calling the method userLogin() for login the user
        findViewById(R.id.btnLogin).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                userLogin();
            }
        });

        //if user presses on textview not register calling RegisterActivity
        findViewById(R.id.tvRegister).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
                startActivity(new Intent(getApplicationContext(), RegisterActivity.class));
            }
        });
    }

    private void userLogin() {
        //first getting the values
        final String username = etName.getText().toString();
        final String password = etPassword.getText().toString();
        //validating inputs
        if (TextUtils.isEmpty(username)) {
            etName.setError("Please enter your username");
            etName.requestFocus();
            return;
        }

        if (TextUtils.isEmpty(password)) {
            etPassword.setError("Please enter your password");
            etPassword.requestFocus();
            return;
        }

        //if everything is fine
        StringRequest stringRequest = new StringRequest(Request.Method.POST, URLs.URL_LOGIN,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        progressBar.setVisibility(View.GONE);

                        try {
                            //converting response to json object
                            JSONObject obj = new JSONObject(response);

                            //if no error in response
                            if (!obj.getBoolean("error")) {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();

                                //getting the user from the response
                                JSONObject userJson = obj.getJSONObject("user");

                                //creating a new user object
                                User user = new User(
                                        userJson.getInt("id"),
                                        userJson.getString("username"),
                                        userJson.getString("email"),
                                        userJson.getString("gender")
                                );

                                //storing the user in shared preferences
                                SharedPrefManager.getInstance(getApplicationContext()).userLogin(user);
                                //starting the profile activity
                                finish();
                                startActivity(new Intent(getApplicationContext(), MainActivity.class));
                            } else {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();
                            }
                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_SHORT).show();

                    }
                })
        {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<>();
                params.put("username", username);
                params.put("password", password);
                return params;
            }
        };

        VolleySingleton.getInstance(this).addToRequestQueue(stringRequest);
    }
}

The RegisterActivity.java class is used to register the user. This class initially checks the user log-in if it is true, then redirect to MainActivity.java class otherwise, allow user for registration.

Similar to LoginActivity.java class, we use the StringRequest class of Volley library for network connection and pass the parameters of the type request method, URL, and the response. The Response.Listener<String>() method handles the response generated by the server.

RegisterActivity.java

package example.javatpoint.com.volleyregistrationloginsystem;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.HashMap;
import java.util.Map;

public class RegisterActivity extends AppCompatActivity {
    EditText editTextUsername, editTextEmail, editTextPassword;
    RadioGroup radioGroupGender;
    ProgressBar progressBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);
        progressBar = findViewById(R.id.progressBar);

        //if the user is already logged in we will directly start the MainActivity (profile) activity
        if (SharedPrefManager.getInstance(this).isLoggedIn()) {
            finish();
            startActivity(new Intent(this, MainActivity.class));
            return;
        }

        editTextUsername = findViewById(R.id.editTextUsername);
        editTextEmail = findViewById(R.id.editTextEmail);
        editTextPassword = findViewById(R.id.editTextPassword);
        radioGroupGender = findViewById(R.id.radioGender);


        findViewById(R.id.buttonRegister).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //if user pressed on button register
                //here we will register the user to server
                registerUser();
            }
        });

        findViewById(R.id.textViewLogin).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //if user pressed on textview that already register open LoginActivity
                finish();
                startActivity(new Intent(RegisterActivity.this, LoginActivity.class));
            }
        });

    }

    private void registerUser() {
        final String username = editTextUsername.getText().toString().trim();
        final String email = editTextEmail.getText().toString().trim();
        final String password = editTextPassword.getText().toString().trim();

        final String gender = ((RadioButton) findViewById(radioGroupGender.getCheckedRadioButtonId())).getText().toString();

        //first we will do the validations
        if (TextUtils.isEmpty(username)) {
            editTextUsername.setError("Please enter username");
            editTextUsername.requestFocus();
            return;
        }

        if (TextUtils.isEmpty(email)) {
            editTextEmail.setError("Please enter your email");
            editTextEmail.requestFocus();
            return;
        }

        if (!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
            editTextEmail.setError("Enter a valid email");
            editTextEmail.requestFocus();
            return;
        }

        if (TextUtils.isEmpty(password)) {
            editTextPassword.setError("Enter a password");
            editTextPassword.requestFocus();
            return;
        }

        StringRequest stringRequest = new StringRequest(Request.Method.POST, URLs.URL_REGISTER,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        progressBar.setVisibility(View.GONE);

                        try {
                            //converting response to json object
                            JSONObject obj = new JSONObject(response);
                            //if no error in response
                            if (!obj.getBoolean("error")) {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();

                                //getting the user from the response
                                JSONObject userJson = obj.getJSONObject("user");

                                //creating a new user object
                                User user = new User(
                                        userJson.getInt("id"),
                                        userJson.getString("username"),
                                        userJson.getString("email"),
                                        userJson.getString("gender")
                                );

                                //storing the user in shared preferences
                                SharedPrefManager.getInstance(getApplicationContext()).userLogin(user);

                                //starting the profile activity
                                finish();
                                startActivity(new Intent(getApplicationContext(), MainActivity.class));
                            } else {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();
                            }
                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                }) {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<>();
                params.put("username", username);
                params.put("email", email);
                params.put("password", password);
                params.put("gender", gender);
                return params;
            }
        };

        VolleySingleton.getInstance(this).addToRequestQueue(stringRequest);
    }
}

Add the following permission in AndroidManifest.xml file

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.INTERNET"/>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="example.javatpoint.com.volleyregistrationloginsystem">
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.INTERNET"/>
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".LoginActivity" />
        <activity android:name=".RegisterActivity"></activity>
    </application>

</manifest>

Output: