Android Login Register Using Volley library, PHP and MySQL database.

Larn Tech | April 16, 2018 | Android | No Comments

Hey guys, Here is another android tutorial for Android Login Register Using Volley library, PHP and MySQL database.
In this tutorial we shall learn a couple of things which include

Designing android login and register form.
Designing android user profile page.
Creating MySQL database for storing user data.
Creating PHP files for handling user registration and login.
Storing user data in MySQL database.
Storing logged in user session in shared preference
Finally we are going to use volley library to send and receive user login register details to and from database

- The output can be seen below.

Android Login Register Using Volley library, PHP and MySQL database.

- How the application operates is very simple way.
- On Successful registration user is directed to login page.
- During login the data user provide is checked against the data in the database
- If data provide during login is found correct user is directed to Profile Page
- As the user is directed to profile his username is stored in shared preference
- The importance of storing the username is to keep session of logged in user so as next time user will not need to logged in again
- If the user clicks logout his data is cleared from shared preference and he is directed to login page

Contents

1 Creating MySQL database
2 Creating PHP files
3 Creating new android project
4 Adding Volley Library to our project
5 Creating Volley library Singleton Class
- 5.1 Creating SharedPref Class
6 Designing Background Gradient for Background
7 Creating Login Form
8 Creating Register Form
9 Creating Profile Page
10 MainActivity Setup
11 RegisterActivity Setup
12 ProfileActivity Setup
13 Requesting Android Permission
14 Share this:
15 Related

Creating MySQL database

- We are going to use MySQL database that comes with XAMPP.
- Ensure you have XAMPP installed you can download it form apachefriends
- Open your xampp and start both Apache and MySQL.
- Open your browser and type localhost/phpmyadmin.
- Create a new database and name it androidusers.
- Select your database and click SQL on the top bar of the page.

SQL

- Copy and Paste the code below and click go.



CREATE TABLE `androidusers`.`Users` ( `id` INT(100) NOT NULL AUTO_INCREMENT , `username` VARCHAR(100) NOT NULL , `useremail` VARCHAR(100) NOT NULL , `password` VARCHAR(100) NOT NULL , PRIMARY KEY (`id`)) ENGINE = InnoDB;

CREATE TABLE `androidusers`.`Users` ( `id` INT(100) NOT NULL AUTO_INCREMENT , `username` VARCHAR(100) NOT NULL , `useremail` VARCHAR(100) NOT NULL , `password` VARCHAR(100) NOT NULL , PRIMARY KEY (`id`)) ENGINE = InnoDB;

- You will get a table similar to the one below.

Android User Table

Creating PHP files

- We are going to create 3 PHP files.
- Frist one is db.php file for connecting to database, Second is login.php file for handling user login and finally register.php file for handling user registration.
- We will use PDO “PHP DATA OBJECT” for connecting to the database.
- Open your directory C:/xampp/htdocs.
- Make a folder and name it android-users.
- Inside that folder create a file and name it db.php “C:/xampp/htdocs/android-users/db.php“.
- Using your best code editor copy and paste the code below in db.php file.
- You can change database credential if yours doesn’t match with the one below



<?php
try{
$host="mysql:host=localhost;dbname=androidusers";
$user_name="root";
$user_password="";
$dbh=new PDO($host,$user_name,$user_password);
}

catch(Exception $e){
exit("Connection Error".$e->getMessage());
}

?>

<?php

try{

$host="mysql:host=localhost;dbname=androidusers";

$user_name="root";

$user_password="";

$dbh=new PDO($host,$user_name,$user_password);

}

catch(Exception $e){

exit("Connection Error".$e->getMessage());

}

- Create another file in android-users folder and name it login.php “C:/xampp/htdocs/android-users/login.php“
- Copy and Paste the code below to your login.php file.



<?php
//getting user values
$email=$_POST['email'];
$password=$_POST['password'];
//an array of response
$output = array();
//requires database connection
require_once('db.php');
//checking if email exit
$conn=$dbh->prepare("SELECT * FROM users WHERE useremail=? and password=?");
$pass=md5($password);
$conn->bindParam(1,$email);
$conn->bindParam(2,$pass);
$conn->execute();
if($conn->rowCount() == 0){
$output['error'] = true;
$output['message'] = "Wrong Email or Password";
}

//checking password correctness
if($conn->rowCount() !==0){
$results=$conn->fetch(PDO::FETCH_OBJ);
//we get both the username and password
$username=$results->username;
$correctpass=$results->password;

$output['error'] = false;
$output['message'] = "login sucessful";
$output['username'] = $username;

}
echo json_encode($output);

?>

<?php

//getting user values

$email=$_POST['email'];

$password=$_POST['password'];

//an array of response

$output = array();

//requires database connection

require_once('db.php');

//checking if email exit

$conn=$dbh->prepare("SELECT * FROM users WHERE useremail=? and password=?");

$pass=md5($password);

$conn->bindParam(1,$email);

$conn->bindParam(2,$pass);

$conn->execute();

if($conn->rowCount() == 0){

$output['error'] = true;

$output['message'] = "Wrong Email or Password";

}

//checking password correctness

if($conn->rowCount() !==0){

$results=$conn->fetch(PDO::FETCH_OBJ);

//we get both the username and password

$username=$results->username;

$correctpass=$results->password;

$output['error'] = false;

$output['message'] = "login sucessful";

$output['username'] = $username;

}

echo json_encode($output);

- Create another file in android-users folder and name it register.php “C:/xampp/htdocs/android-users/register.php“
- Copy and Paste the code below to your register.php file.



<?php

//getting user values
$username=$_POST['username'];
$email=$_POST['email'];
$password=$_POST['password'];

//array of responses
$output=array();

//require database
require_once('db.php');

//checking if email exists
$conn=$dbh->prepare('SELECT useremail FROM users WHERE useremail=?');
$conn->bindParam(1,$email);
$conn->execute();

//results
if($conn->rowCount() !==0){
$output['error'] = true;
$output['message'] = "Email Exists Please Login";
}else{

$conn=$dbh->prepare('INSERT INTO users(username,useremail,password) VALUES (?,?,?)');
//encrypting the password
$pass=md5($password);
$conn->bindParam(1,$username);
$conn->bindParam(2,$email);
$conn->bindParam(3,$pass);

$conn->execute();
if($conn->rowCount() == 0)
{
$output['error'] = true;
$output['message'] = "Registration failed, Please try again";
}
elseif($conn->rowCount() !==0){
$output['error'] = false;
$output['message'] = "Succefully Registered";
$output['username']=$username;
}
}
echo json_encode($output);

?>

<?php

//getting user values

$username=$_POST['username'];

$email=$_POST['email'];

$password=$_POST['password'];

//array of responses

$output=array();

//require database

require_once('db.php');

//checking if email exists

$conn=$dbh->prepare('SELECT useremail FROM users WHERE useremail=?');

$conn->bindParam(1,$email);

$conn->execute();

//results

if($conn->rowCount() !==0){

$output['error'] = true;

$output['message'] = "Email Exists Please Login";

}else{

$conn=$dbh->prepare('INSERT INTO users(username,useremail,password) VALUES (?,?,?)');

//encrypting the password

$pass=md5($password);

$conn->bindParam(1,$username);

$conn->bindParam(2,$email);

$conn->bindParam(3,$pass);

$conn->execute();

if($conn->rowCount() == 0)

{

$output['error'] = true;

$output['message'] = "Registration failed, Please try again";

}

elseif($conn->rowCount() !==0){

$output['error'] = false;

$output['message'] = "Succefully Registered";

$output['username']=$username;

}

echo json_encode($output);

- Now we are done on web part. We get started on android part.

Creating new android project

- Open your android studio click File => New Project.
- Give it a name you can all it LoginRegister.
- Click Next = > Empty activity => finish.

Adding Volley Library to our project

- Volley library is used for transmitting network data.
- We will use volley to help us pass data from android app to our MySQL database.
- You can learn more about from here
- Include the code below in your build.gradle file .



compile 'com.android.volley:volley:1.0.0'

compile 'com.android.volley:volley:1.0.0'

Adding Volley Library

Creating Volley library Singleton Class

- To improve volley efficiency we will create VolleySingleton class.
- This class will help use to encapsulate RequestQueue and other volley functionality.
- Create a java class by right clicking on java folder => new => java class and name it VolleySingleton.
- Open VolleySingleton and paste the code below.



package com.example.kamere.loginregister;
import android.content.Context;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.Volley;
/**
 * Created by Kamere on 4/15/2018.
 */
    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 &lt;> void addToRequestQueue(Request&lt;> req) {
            getRequestQueue().add(req);
        }
    }

package com.example.kamere.loginregister;

import android.content.Context;

import com.android.volley.Request;

import com.android.volley.RequestQueue;

import com.android.volley.toolbox.Volley;

/**

* Created by Kamere on 4/15/2018.

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 <> void addToRequestQueue(Request<> req) {

getRequestQueue().add(req);

}

Creating SharedPref Class

- To keep session of logged in user in android we will use shared preference.
- In our shared preference we shall create a storage file and name it larntech.
- We shall Create username key for storing the name of the logged in user.
- We will create methods to store user data, to check is user is logged in and to logout user.
- Create a java class by right clicking on java folder => new => java class and name it Sharedpref.
- Copy and paste the code below to your SharedPref file.



package com.example.kamere.loginregister;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;

/**
 * Created by Kamere on 4/15/2018.
 */

public class SharedPref {

    //Storage File
    public static final String SHARED_PREF_NAME = "larntech";

    //Username
    public static final String USER_NAME = "username";

    public static SharedPref mInstance;

    public static Context mCtx;


    public SharedPref(Context context) {
        mCtx = context;
    }


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


    //method to store user data
    public void storeUserName(String names) {
        SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putString(USER_NAME, names);
        editor.commit();
    }

    //check if user is logged in
    public boolean isLoggedIn() {
        SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        return sharedPreferences.getString(USER_NAME, null) != null;
    }


    //find logged in user
    public String LoggedInUser() {
        SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        return sharedPreferences.getString(USER_NAME, null);

    }


    //Logout user
    public void logout() {
        SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.clear();
        editor.commit();
        mCtx.startActivity(new Intent(mCtx, MainActivity.class));
    }

}

package com.example.kamere.loginregister;

import android.content.Context;

import android.content.Intent;

import android.content.SharedPreferences;

/**

* Created by Kamere on 4/15/2018.

public class SharedPref {

//Storage File

public static final String SHARED_PREF_NAME = "larntech";

//Username

public static final String USER_NAME = "username";

public static SharedPref mInstance;

public static Context mCtx;

public SharedPref(Context context) {

mCtx = context;

}

public static synchronized SharedPref getInstance(Context context) {

if (mInstance == null) {

mInstance = new SharedPref(context);

}

return mInstance;

}

//method to store user data

public void storeUserName(String names) {

SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);

SharedPreferences.Editor editor = sharedPreferences.edit();

editor.putString(USER_NAME, names);

editor.commit();

}

//check if user is logged in

public boolean isLoggedIn() {

SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);

return sharedPreferences.getString(USER_NAME, null) != null;

}

//find logged in user

public String LoggedInUser() {

SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);

return sharedPreferences.getString(USER_NAME, null);

}

//Logout user

public void logout() {

SharedPreferences sharedPreferences = mCtx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);

SharedPreferences.Editor editor = sharedPreferences.edit();

editor.clear();

editor.commit();

mCtx.startActivity(new Intent(mCtx, MainActivity.class));

}

Designing Background Gradient for Background

- Create a new file in your drawable folder and call it background_color.xml .

Android gradient color

- Open that file and paste the code below.



<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<!-- Bottom 2dp Shadow -->
<item>
    <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="rectangle">
        <gradient
            android:endColor="#f96304d1"
            android:startColor="#d0538abe"
            android:centerX="90%"
            android:centerY="100%"
            android:type="linear"
            android:angle="135"/>
      </shape>
</item>
</layer-list>

<?xml version="1.0" encoding="utf-8"?>

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

<item>

<shape xmlns:android="http://schemas.android.com/apk/res/android"

android:shape="rectangle">

<gradient

android:endColor="#f96304d1"

android:startColor="#d0538abe"

android:centerX="90%"

android:centerY="100%"

android:type="linear"

android:angle="135"/>

</shape>

</item>

</layer-list>

- Background preview will look as shown below.

Background Gradient Color

- Open colors.xml file located under values folder and change the primary color to match with the background.
- Copy and Paste the code below to your colors.xml file



<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#6823cf</color>
    <color name="colorPrimaryDark">#6a32cf</color>
    <color name="colorAccent">#f2f2f2</color>
</resources>

<?xml version="1.0" encoding="utf-8"?>

</resources>

- Open your styles.xml file located under values folder and include NoActionBar theme.
- Copy and Paste the code below in your styles.xml



   <resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>
    <style name="AppTheme.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
        <item name="colorControlHighlight">#4db9b5ba</item>
    </style>

</resources>

<item name="colorPrimary">@color/colorPrimary</item>

<item name="colorPrimaryDark">@color/colorPrimaryDark</item>

<item name="colorAccent">@color/colorAccent</item>

</style>

<item name="windowActionBar">false</item>

</style>

</resources>

Creating Login Form

- The login form will contain email and password edit text, Login Button and Register page link.
- Open your activity_main file which is under Res => Layout => activity_main.
- Copy and paste the code below to your activity_main file.


<?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:background="@drawable/background_color"
tools:context="com.example.kamere.loginregister.MainActivity">
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="61dp"
    android:text="Login Your Account"
    android:textColor="#fff"
    android:textSize="25dp"
    android:textStyle="bold|normal" />

<EditText
    android:id="@+id/loginEmail"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="Email"
    android:inputType="text"
    android:paddingBottom="18dp"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"
    android:layout_marginTop="190dp"
    android:textColor="#fff"
    android:textColorHint="#ffffff"
    android:backgroundTint="#cda7f4"
    android:textSize="10pt" />

<EditText
    android:id="@+id/loginPassword"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/loginEmail"
    android:hint="Password"
    android:inputType="textPassword"
    android:paddingBottom="18dp"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"
    android:textColor="#fff"
    android:textColorHint="#ffffff"
    android:backgroundTint="#cda7f4"
    android:textSize="10pt" />
<Button
    android:id="@+id/btnLogin"
    android:layout_width="match_parent"
    android:layout_height="120px"
    android:paddingRight="30dp"
    android:paddingLeft="30dp"
    android:layout_marginTop="15dp"
    android:layout_below="@+id/loginPassword"
    android:layout_centerHorizontal="true"
    android:background="#c85ae49a"
    android:text="Login"
    android:textAllCaps="false"
    android:textColor="#ffffff"
    android:textSize="58px" />

<TextView
    android:id="@+id/register"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/btnLogin"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="15dp"
    android:textSize="20dp"
    android:text="Or Register"
    android:textColor="#fff"

    />
</RelativeLayout>

<?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:background="@drawable/background_color"

tools:context="com.example.kamere.loginregister.MainActivity">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentTop="true"

android:layout_centerHorizontal="true"

android:layout_marginTop="61dp"

android:text="Login Your Account"

android:textColor="#fff"

android:textSize="25dp"

android:textStyle="bold|normal" />

<EditText

android:id="@+id/loginEmail"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:hint="Email"

android:inputType="text"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:layout_marginTop="190dp"

android:textColor="#fff"

android:textColorHint="#ffffff"

android:backgroundTint="#cda7f4"

android:textSize="10pt" />

<EditText

android:id="@+id/loginPassword"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@+id/loginEmail"

android:hint="Password"

android:inputType="textPassword"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:textColor="#fff"

android:textColorHint="#ffffff"

android:backgroundTint="#cda7f4"

android:textSize="10pt" />

<Button

android:id="@+id/btnLogin"

android:layout_width="match_parent"

android:layout_height="120px"

android:paddingRight="30dp"

android:paddingLeft="30dp"

android:layout_marginTop="15dp"

android:layout_below="@+id/loginPassword"

android:layout_centerHorizontal="true"

android:background="#c85ae49a"

android:text="Login"

android:textAllCaps="false"

android:textColor="#ffffff"

android:textSize="58px" />

<TextView

android:id="@+id/register"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_below="@+id/btnLogin"

android:layout_centerHorizontal="true"

android:layout_marginTop="15dp"

android:textSize="20dp"

android:text="Or Register"

android:textColor="#fff"

</RelativeLayout>

- The form should appear as shown below.

Android Login Form

- To remove ActionBar open Manifest file add theme No Action Bar to your MainActivity.



<activity
 android:name=".MainActivity"
 android:theme="@style/AppTheme.NoActionBar">
</activity>

<activity

android:name=".MainActivity"

android:theme="@style/AppTheme.NoActionBar">

</activity>

Creating Register Form

- Create an Empty Activity.
- right click Layout => New => Activity => Empty Activity and Name it activity_register.
- Register form will contain username,email,password and confirm password fields, register button and link to login page.
- Open activity_register and copy paste the code below.



<?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:background="@drawable/background_color"
    tools:context="com.example.kamere.loginregister.RegisterActivity">
">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="51dp"
            android:text="Create Account"
            android:textColor="#fff"
            android:textSize="25dp"
            android:textStyle="bold|normal" />
        <EditText
            android:id="@+id/registerName"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="130dp"
            android:hint="Username"
            android:inputType="text"
            android:paddingBottom="18dp"
            android:paddingLeft="8dp"
            android:paddingRight="8dp"
            android:textColor="#fff"
            android:textColorHint="#ffffff"
            android:backgroundTint="#e6d9f4"
            android:textSize="10pt" />
        <EditText
            android:id="@+id/registerEmail"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@id/registerName"
            android:hint="Email"
            android:inputType="text"
            android:paddingBottom="18dp"
            android:paddingLeft="8dp"
            android:paddingRight="8dp"
            android:textColor="#fff"
            android:textColorHint="#ffffff"
            android:backgroundTint="#e6d9f4"
            android:textSize="10pt" />

        <EditText
            android:id="@+id/registerPassword"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/registerEmail"
            android:hint="Password"
            android:inputType="textPassword"
            android:paddingBottom="18dp"
            android:paddingLeft="8dp"
            android:paddingRight="8dp"
            android:textColor="#fff"
            android:textColorHint="#fff"
            android:backgroundTint="#e6d9f4"
            android:textSize="10pt" />
        <EditText
            android:id="@+id/confirmpassword"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/registerPassword"
            android:hint="Confirm Password"
            android:inputType="textPassword"
            android:paddingBottom="18dp"
            android:paddingLeft="8dp"
            android:paddingRight="8dp"
            android:textColor="#fff"
            android:textColorHint="#ffffff"
            android:backgroundTint="#e6d9f4"
            android:textSize="10pt" />

        <Button
            android:id="@+id/btnRegister"
            android:layout_width="match_parent"
            android:layout_height="120px"
            android:paddingRight="30dp"
            android:paddingLeft="30dp"
            android:layout_marginTop="15dp"
            android:layout_below="@+id/confirmpassword"
            android:layout_centerHorizontal="true"
            android:text="Register"
            android:textAllCaps="false"
            android:textColor="#ffffff"
            android:background="#c85ae49a"
            android:textSize="58px" />

        <TextView
            android:id="@+id/login"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/btnRegister"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="15dp"
            android:textSize="20dp"
            android:text="Or Login"
            android:textColor="#fff"
            />
    </RelativeLayout>

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<?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:background="@drawable/background_color"

tools:context="com.example.kamere.loginregister.RegisterActivity">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentTop="true"

android:layout_centerHorizontal="true"

android:layout_marginTop="51dp"

android:text="Create Account"

android:textColor="#fff"

android:textSize="25dp"

android:textStyle="bold|normal" />

<EditText

android:id="@+id/registerName"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="130dp"

android:hint="Username"

android:inputType="text"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:textColor="#fff"

android:textColorHint="#ffffff"

android:backgroundTint="#e6d9f4"

android:textSize="10pt" />

<EditText

android:id="@+id/registerEmail"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@id/registerName"

android:hint="Email"

android:inputType="text"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:textColor="#fff"

android:textColorHint="#ffffff"

android:backgroundTint="#e6d9f4"

android:textSize="10pt" />

<EditText

android:id="@+id/registerPassword"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@+id/registerEmail"

android:hint="Password"

android:inputType="textPassword"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:textColor="#fff"

android:textColorHint="#fff"

android:backgroundTint="#e6d9f4"

android:textSize="10pt" />

<EditText

android:id="@+id/confirmpassword"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@+id/registerPassword"

android:hint="Confirm Password"

android:inputType="textPassword"

android:paddingBottom="18dp"

android:paddingLeft="8dp"

android:paddingRight="8dp"

android:textColor="#fff"

android:textColorHint="#ffffff"

android:backgroundTint="#e6d9f4"

android:textSize="10pt" />

<Button

android:id="@+id/btnRegister"

android:layout_width="match_parent"

android:layout_height="120px"

android:paddingRight="30dp"

android:paddingLeft="30dp"

android:layout_marginTop="15dp"

android:layout_below="@+id/confirmpassword"

android:layout_centerHorizontal="true"

android:text="Register"

android:textAllCaps="false"

android:textColor="#ffffff"

android:background="#c85ae49a"

android:textSize="58px" />

<TextView

android:id="@+id/login"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_below="@+id/btnRegister"

android:layout_centerHorizontal="true"

android:layout_marginTop="15dp"

android:textSize="20dp"

android:text="Or Login"

android:textColor="#fff"

</RelativeLayout>

- The output for register activity will be as shown below.

Android Best Register Form

- To remove ActionBar open Manifest file add theme No Action Bar to your RegisterActivity.



 <activity android:name=".RegisterActivity"
            android:theme="@style/AppTheme.NoActionBar"
            android:label="Register">
</activity>

<activity android:name=".RegisterActivity"

android:theme="@style/AppTheme.NoActionBar"

android:label="Register">

</activity>

Creating Profile Page

- Create an Empty Activity right click Layout => New => Activity => Empty Activity and Name it activity_profile.
- Profile page will display the name of logged in user and a logout button.
- Copy and Paste the code below in your activity_profile



<?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"
    tools:context="com.example.kamere.loginregister.ProfileActivity">

    <TextView
        android:id="@+id/username"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true"
        android:layout_marginStart="32dp"
        android:layout_marginTop="68dp"
        android:text="Username : "
        android:textColor="#000"
        android:textSize="20dp"
        android:textStyle="normal|bold" />

    <Button
        android:id="@+id/btnLogout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignStart="@+id/username"
        android:layout_below="@+id/username"
        android:layout_marginTop="50dp"
        android:background="#f5e966"
        android:text="Log Out"
        android:textAllCaps="false"
        android:textColor="#000"
        android:textSize="15dp" />
</RelativeLayout>

<?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"

tools:context="com.example.kamere.loginregister.ProfileActivity">

<TextView

android:id="@+id/username"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentStart="true"

android:layout_alignParentTop="true"

android:layout_marginStart="32dp"

android:layout_marginTop="68dp"

android:text="Username : "

android:textColor="#000"

android:textSize="20dp"

android:textStyle="normal|bold" />

<Button

android:id="@+id/btnLogout"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignStart="@+id/username"

android:layout_below="@+id/username"

android:layout_marginTop="50dp"

android:background="#f5e966"

android:text="Log Out"

android:textAllCaps="false"

android:textColor="#000"

android:textSize="15dp" />

</RelativeLayout>

- The output will be similar to image below

MainActivity Setup

- Open your MainActivity located at java => your package => MainActivity.
- This class will handle your login form.
- Receives data from activity_main and pass it to login.php .
- Remember to change loginURL to match you url.
- Copy and paste the code below in your MainActivity.java.



package com.example.kamere.loginregister;

import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Vibrator;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
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 MainActivity extends AppCompatActivity {
EditText email_input,password_input;
TextView register;
Button btnLogin;
Vibrator v;

//change this to match your url
final String loginURL = "http://192.168.43.254/android-users/login.php";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        email_input = findViewById(R.id.loginEmail);
        password_input = findViewById(R.id.loginPassword);
        register = findViewById(R.id.register);
        btnLogin = findViewById(R.id.btnLogin);
        v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);

        btnLogin.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                validateUserData();
            }
        });

        //when someone clicks on login
        register.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(getApplicationContext(),RegisterActivity.class);
                startActivity(intent);
            }
        });

    }
    private void validateUserData() {

        //first getting the values
        final String email = email_input.getText().toString();
        final String password = password_input.getText().toString();

        //checking if email is empty
        if (TextUtils.isEmpty(email)) {
            email_input.setError("Please enter your email");
            email_input.requestFocus();
            // Vibrate for 100 milliseconds
            v.vibrate(100);
            btnLogin.setEnabled(true);
            return;
        }
        //checking if password is empty
        if (TextUtils.isEmpty(password)) {
            password_input.setError("Please enter your password");
            password_input.requestFocus();
            //Vibrate for 100 milliseconds
            v.vibrate(100);
            btnLogin.setEnabled(true);
            return;
        }
        //validating email
        if (!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
            email_input.setError("Enter a valid email");
            email_input.requestFocus();
            //Vibrate for 100 milliseconds
            v.vibrate(100);
            btnLogin.setEnabled(true);
            return;
        }


        //Login User if everything is fine
        loginUser();


    }

    private void loginUser() {

        //first getting the values
        final String email = email_input.getText().toString();
        final String password = password_input.getText().toString();



        //Call our volley library
        StringRequest stringRequest = new StringRequest(Request.Method.POST,loginURL,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {

                        try {
//                            Toast.makeText(getApplicationContext(),response.toString(), Toast.LENGTH_SHORT).show();

                            JSONObject obj = new JSONObject(response);
                            if (obj.getBoolean("error")) {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();
                            } else {

                                //getting user name
                                String Username = obj.getString("username");
                                Toast.makeText(getApplicationContext(),Username, Toast.LENGTH_SHORT).show();

                                //storing the user in shared preferences
                                SharedPref.getInstance(getApplicationContext()).storeUserName(Username);
                                //starting the profile activity
                                finish();
                                startActivity(new Intent(getApplicationContext(), ProfileActivity.class));

                            }



                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(getApplicationContext(),"Connection Error"+error, Toast.LENGTH_SHORT).show();
                        error.printStackTrace();
                    }
                }) {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<>();
                params.put("email", email);
                params.put("password", password);

                return params;
            }
        };
        VolleySingleton.getInstance(MainActivity.this).addToRequestQueue(stringRequest);
    }



}

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package com.example.kamere.loginregister;

import android.content.Context;

import android.content.Intent;

import android.content.SharedPreferences;

import android.os.Vibrator;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.text.TextUtils;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.TextView;

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 MainActivity extends AppCompatActivity {

EditText email_input,password_input;

TextView register;

Button btnLogin;

Vibrator v;

//change this to match your url

final String loginURL = "http://192.168.43.254/android-users/login.php";

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

email_input = findViewById(R.id.loginEmail);

password_input = findViewById(R.id.loginPassword);

btnLogin = findViewById(R.id.btnLogin);

v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);

btnLogin.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

validateUserData();

}

});

//when someone clicks on login

@Override

public void onClick(View view) {

Intent intent = new Intent(getApplicationContext(),RegisterActivity.class);

startActivity(intent);

}

});

}

private void validateUserData() {

//first getting the values

final String email = email_input.getText().toString();

final String password = password_input.getText().toString();

//checking if email is empty

if (TextUtils.isEmpty(email)) {

email_input.setError("Please enter your email");

email_input.requestFocus();

// Vibrate for 100 milliseconds

v.vibrate(100);

btnLogin.setEnabled(true);

return;

}

//checking if password is empty

if (TextUtils.isEmpty(password)) {

password_input.setError("Please enter your password");

password_input.requestFocus();

//Vibrate for 100 milliseconds

v.vibrate(100);

btnLogin.setEnabled(true);

return;

}

//validating email

if (!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {

email_input.setError("Enter a valid email");

email_input.requestFocus();

//Vibrate for 100 milliseconds

v.vibrate(100);

btnLogin.setEnabled(true);

return;

}

//Login User if everything is fine

loginUser();

}

private void loginUser() {

//first getting the values

final String email = email_input.getText().toString();

final String password = password_input.getText().toString();

//Call our volley library

StringRequest stringRequest = new StringRequest(Request.Method.POST,loginURL,

new Response.Listener<String>() {

@Override

public void onResponse(String response) {

try {

// Toast.makeText(getApplicationContext(),response.toString(), Toast.LENGTH_SHORT).show();

JSONObject obj = new JSONObject(response);

if (obj.getBoolean("error")) {

Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();

} else {

//getting user name

String Username = obj.getString("username");

Toast.makeText(getApplicationContext(),Username, Toast.LENGTH_SHORT).show();

//storing the user in shared preferences

SharedPref.getInstance(getApplicationContext()).storeUserName(Username);

//starting the profile activity

finish();

startActivity(new Intent(getApplicationContext(), ProfileActivity.class));

}

} catch (JSONException e) {

e.printStackTrace();

}

new Response.ErrorListener() {

@Override

public void onErrorResponse(VolleyError error) {

Toast.makeText(getApplicationContext(),"Connection Error"+error, Toast.LENGTH_SHORT).show();

error.printStackTrace();

}

}) {

@Override

protected Map<String, String> getParams() throws AuthFailureError {

Map<String, String> params = new HashMap<>();

params.put("email", email);

params.put("password", password);

return params;

}

};

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

}

RegisterActivity Setup

Open your RegisterActivity class located at java => your package => RegisterActivity.

- This file handles user registration.
- Receives data from activity_register and pass it to register.php.
- register.php inserts the data in the database and then user is directed to login page.
- Copy and Paste the code below to your RegisterActivity.java file



public class RegisterActivity extends AppCompatActivity {
EditText username,email,password,cpassword;
TextView login;
Button btnRegister;
Vibrator v;
//change to your register url
final String registerUrl = "http://192.168.43.254/android-users/register.php";

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

        username = (EditText) findViewById(R.id.registerName);
        email = (EditText) findViewById(R.id.registerEmail);
        password = (EditText) findViewById(R.id.confirmpassword);
        cpassword = (EditText) findViewById(R.id.confirmpassword);
        btnRegister = (Button) findViewById(R.id.btnRegister);
        login = (TextView) findViewById(R.id.login);
        v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);

        btnRegister.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                validateUserData();
            }
        });
       login.setOnClickListener(new View.OnClickListener() {
           @Override
           public void onClick(View view) {
               Intent intent = new Intent(getApplicationContext(),MainActivity.class);
               startActivity(intent);
           }
       });

    }

    private void validateUserData() {

        //find values
        final String reg_name = username.getText().toString();
        final String reg_email = email.getText().toString();
        final String reg_password = cpassword.getText().toString();
        final String reg_cpassword = cpassword.getText().toString();


//        checking if username is empty
        if (TextUtils.isEmpty(reg_name)) {
            username.setError("Please enter username");
            username.requestFocus();
            // Vibrate for 100 milliseconds
            v.vibrate(100);
            return;
        }
        //checking if email is empty
        if (TextUtils.isEmpty(reg_email)) {
            email.setError("Please enter email");
            email.requestFocus();
            // Vibrate for 100 milliseconds
            v.vibrate(100);
            return;
        }
        //checking if password is empty
        if (TextUtils.isEmpty(reg_password)) {
            password.setError("Please enter password");
            password.requestFocus();
            //Vibrate for 100 milliseconds
            v.vibrate(100);
            return;
        }
        //validating email
        if (!android.util.Patterns.EMAIL_ADDRESS.matcher(reg_email).matches()) {
            email.setError("Enter a valid email");
            email.requestFocus();
            //Vibrate for 100 milliseconds
            v.vibrate(100);
            return;
        }
        //checking if password matches
        if (!reg_password.equals(reg_cpassword)) {
            password.setError("Password Does not Match");
            password.requestFocus();
            //Vibrate for 100 milliseconds
            v.vibrate(100);
            return;
        }

        //After Validating we register User
        registerUser();

    }

    private void registerUser() {


        final String reg_username = username.getText().toString();
        final String reg_email = email.getText().toString();
        final String reg_password = cpassword.getText().toString();




        //Call our volley library
        StringRequest stringRequest = new StringRequest(Request.Method.POST,registerUrl,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {

                        try {

                            JSONObject obj = new JSONObject(response);
                            if (obj.getBoolean("error")) {
                                Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();
                            } else {


                                //starting the login activity
                                startActivity(new Intent(getApplicationContext(),MainActivity.class));

                            }



                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(getApplicationContext(),"Connection Error"+error, Toast.LENGTH_SHORT).show();
                        error.printStackTrace();
                    }
                }) {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<>();
                params.put("username",reg_username);
                params.put("email", reg_email);
                params.put("password", reg_password);

                return params;
            }
        };
        VolleySingleton.getInstance(RegisterActivity.this).addToRequestQueue(stringRequest);
    }

}

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public class RegisterActivity extends AppCompatActivity {

EditText username,email,password,cpassword;

TextView login;

Button btnRegister;

Vibrator v;

//change to your register url

final String registerUrl = "http://192.168.43.254/android-users/register.php";

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_register);

username = (EditText) findViewById(R.id.registerName);

email = (EditText) findViewById(R.id.registerEmail);

password = (EditText) findViewById(R.id.confirmpassword);

cpassword = (EditText) findViewById(R.id.confirmpassword);

btnRegister = (Button) findViewById(R.id.btnRegister);

v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);

btnRegister.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

validateUserData();

}

});

@Override

public void onClick(View view) {

Intent intent = new Intent(getApplicationContext(),MainActivity.class);

startActivity(intent);

}

});

}

private void validateUserData() {

//find values

final String reg_name = username.getText().toString();

final String reg_email = email.getText().toString();

final String reg_password = cpassword.getText().toString();

final String reg_cpassword = cpassword.getText().toString();

// checking if username is empty

if (TextUtils.isEmpty(reg_name)) {

username.setError("Please enter username");

username.requestFocus();

// Vibrate for 100 milliseconds

v.vibrate(100);

return;

}

//checking if email is empty

if (TextUtils.isEmpty(reg_email)) {

email.setError("Please enter email");

email.requestFocus();

// Vibrate for 100 milliseconds

v.vibrate(100);

return;

}

//checking if password is empty

if (TextUtils.isEmpty(reg_password)) {

password.setError("Please enter password");

password.requestFocus();

//Vibrate for 100 milliseconds

v.vibrate(100);

return;

}

//validating email

if (!android.util.Patterns.EMAIL_ADDRESS.matcher(reg_email).matches()) {

email.setError("Enter a valid email");

email.requestFocus();

//Vibrate for 100 milliseconds

v.vibrate(100);

return;

}

//checking if password matches

if (!reg_password.equals(reg_cpassword)) {

password.setError("Password Does not Match");

password.requestFocus();

//Vibrate for 100 milliseconds

v.vibrate(100);

return;

}

//After Validating we register User

registerUser();

}

private void registerUser() {

final String reg_username = username.getText().toString();

final String reg_email = email.getText().toString();

final String reg_password = cpassword.getText().toString();

//Call our volley library

StringRequest stringRequest = new StringRequest(Request.Method.POST,registerUrl,

new Response.Listener<String>() {

@Override

public void onResponse(String response) {

try {

JSONObject obj = new JSONObject(response);

if (obj.getBoolean("error")) {

Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();

} else {

//starting the login activity

startActivity(new Intent(getApplicationContext(),MainActivity.class));

}

} catch (JSONException e) {

e.printStackTrace();

}

new Response.ErrorListener() {

@Override

public void onErrorResponse(VolleyError error) {

Toast.makeText(getApplicationContext(),"Connection Error"+error, Toast.LENGTH_SHORT).show();

error.printStackTrace();

}

}) {

@Override

protected Map<String, String> getParams() throws AuthFailureError {

Map<String, String> params = new HashMap<>();

params.put("username",reg_username);

params.put("email", reg_email);

params.put("password", reg_password);

return params;

}

};

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

}

ProfileActivity Setup

- Open your ProfileActivity class located at java => your package => ProfileActivity.
- Oncreate method will check if user is logged in.
- If the user is logged in we will get the username stored in the shared preference and display it.
- if user is not logged in he/she will be redirected to login page.
- When logout button is clicked user data is cleared and is redirected to login page.
- Copy and Paste the code below to your ProfileActivity class.



package com.example.kamere.loginregister;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class ProfileActivity extends AppCompatActivity {
TextView username;
Button btnLogout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_profile);

username = findViewById(R.id.username);
btnLogout = findViewById(R.id.btnLogout);

//check if user is logged in
if (!SharedPref.getInstance(this).isLoggedIn()) {
startActivity(new Intent(this, MainActivity.class));
finish();
}

//getting logged in user name
String loggedUsename = SharedPref.getInstance(this).LoggedInUser();
username.setText("Username : "+loggedUsename);

//logging out
btnLogout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
SharedPref.getInstance(getApplicationContext()).logout();
}
});

}

}

package com.example.kamere.loginregister;

import android.content.Intent;

import android.content.SharedPreferences;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

import android.widget.Toast;

public class ProfileActivity extends AppCompatActivity {

TextView username;

Button btnLogout;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_profile);

username = findViewById(R.id.username);

btnLogout = findViewById(R.id.btnLogout);

//check if user is logged in

if (!SharedPref.getInstance(this).isLoggedIn()) {

startActivity(new Intent(this, MainActivity.class));

finish();

}

//getting logged in user name

String loggedUsename = SharedPref.getInstance(this).LoggedInUser();

username.setText("Username : "+loggedUsename);

//logging out

btnLogout.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

finish();

SharedPref.getInstance(getApplicationContext()).logout();

}

});

}

Requesting Android Permission

- The final step is to add permission in the manifest file
- Include the permission below in your manifest file.



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

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

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

- To Declare ProfileActivity as the launcher activity, Include the code below in your manifest file at .ProfileActivity


    
        
public class ProfileActivity extends AppCompatActivity {
    TextView username;
    Button btnLogout;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profile);

        username = findViewById(R.id.username);
        btnLogout = findViewById(R.id.btnLogout);

        //check if user is logged in
        if (!SharedPref.getInstance(this).isLoggedIn()) {
            startActivity(new Intent(this, MainActivity.class));
            finish();
        }

        //getting logged in user name
        String loggedUsename = SharedPref.getInstance(this).LoggedInUser();
        username.setText("Username : "+loggedUsename);

        //logging out
        btnLogout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
                SharedPref.getInstance(getApplicationContext()).logout();
            }
        });


    }


}

public class ProfileActivity extends AppCompatActivity {

TextView username;

Button btnLogout;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_profile);

username = findViewById(R.id.username);

btnLogout = findViewById(R.id.btnLogout);

//check if user is logged in

if (!SharedPref.getInstance(this).isLoggedIn()) {

startActivity(new Intent(this, MainActivity.class));

finish();

}

//getting logged in user name

String loggedUsename = SharedPref.getInstance(this).LoggedInUser();

username.setText("Username : "+loggedUsename);

//logging out

btnLogout.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

finish();

SharedPref.getInstance(getApplicationContext()).logout();

}

});

}

- The final code for your manifest file should look like the one below.



 
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.kamere.loginregister">

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

    <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"
            android:theme="@style/AppTheme.NoActionBar"></activity>
        <activity android:name=".ProfileActivity"
            android:label="Profile"
            >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".RegisterActivity"
            android:theme="@style/AppTheme.NoActionBar"
            android:label="Register"
            ></activity>
    </application>

</manifest>