Loading your workspace…

Beginner 30 min Java Full project

Login and Register App with SQLite in Android Studio (2024)

Build a complete login and registration app that stores users in a local SQLite database. Register a user, sign in, and land on a home screen: the foundation of most real apps.

Download project ZIP View on GitHub Watch on YouTube

6.5Kviews99likes

What you'll learn

Create a users table with SQLiteOpenHelper
Register users and block duplicates
Check a username and password at login
Move between screens with Intents

Before you start

Android Studio (any recent version)
Basic Java: variables, methods and if/else
An emulator or an Android phone

How it fits together

1Register screen
2DatabaseHelper
3Users table
4Login screen
5Home screen

Build it step by step

1. Create the project

In Android Studio choose New Project → Empty Views Activity, with Language Java and Minimum SDK API 24. To copy the code below unchanged, use the package name com.example.loginregistersqlite.

2. Add two more screens

Right-click your package and choose New → Activity → Empty Views Activity twice, to create RegisterActivity and HomeActivity. Android Studio adds both to the manifest for you.

3. Build the three layouts

Login: a title, a username box, a password box, a Login button and a "Register here" link.
Register: the same form with a Sign up button and a "Login here" link.
Home: a welcome message and a Log out button.

Give the password box android:inputType="textPassword" so it shows dots, not letters.

4. Create the database helper

Add a class DatabaseHelper that extends SQLiteOpenHelper. Its onCreate makes a Users table with a UNIQUE username, so the same name can't register twice.

5. Never store passwords as typed

When someone registers, insertData creates a random salt, mixes it with the password and stores only the SHA-256 hash. At login, checkLogin repeats the same mix and compares the results. Even if someone copies the database, they can't read the passwords.

6. Register a user

In RegisterActivity, read both boxes when Sign up is tapped. If either is empty, show a message. Otherwise call insertData: true means success and opens Home, false means the username is taken.

7. Log in

In MainActivity, call checkLogin. It returns the username when the details match and null when they don't. On success, open HomeActivity and pass the name with intent.putExtra("USERNAME", ...).

8. Log out

HomeActivity shows "Welcome name". Log out and the Back button both return to the login screen.

9. Run and test

Register alex with any password. You land on Home.
Log out, then log in with the same details.
Try a wrong password: you'll see Wrong username or password.
Try registering alex again: you'll see That username is already taken.

If something goes wrong

The app crashes on Sign up: check that RegisterActivity and HomeActivity are in AndroidManifest.xml.
"Already taken" never appears: the username column needs UNIQUE. If you changed the table, uninstall the app once so it's recreated.
See the stored users: open App Inspection → Database Inspector while the app runs. You'll see hashes, not passwords.

What's improved over the video

Usernames are unique, passwords are hashed with a salt, the password box hides what you type, Back logs you out cleanly, and the screens respect Android 15's edge-to-edge layout.

Files affected

Check what to add and what to replace before copying code.

app/src/main/AndroidManifest.xmlMerge additions
app/src/main/java/com/example/loginregistersqlite/MainActivity.javaReplace file
app/src/main/res/layout/activity_home.xmlAdd these lines
app/src/main/res/layout/activity_main.xmlReplace file
app/src/main/res/layout/activity_register.xmlAdd these lines
app/src/main/res/values/colors.xmlReplace file
app/src/main/java/com/example/loginregistersqlite/DatabaseHelper.javaAdd these lines
app/src/main/java/com/example/loginregistersqlite/HomeActivity.javaAdd these lines
app/src/main/java/com/example/loginregistersqlite/RegisterActivity.javaAdd these lines
app/src/main/java/com/example/loginregistersqlite/Screens.javaAdd these lines
app/src/main/res/values/strings.xmlReplace file
app/src/main/res/values/themes.xmlReplace file

Required setup

These are additions to an existing project—not replacement project files.

Register the two new screens

Merge additions

Where: app/src/main/AndroidManifest.xml

Add both activity entries inside your existing application element.

app/src/main/AndroidManifest.xml

<application ...>
    <activity
        android:name=".HomeActivity"
        android:exported="false" />
    <activity
        android:name=".RegisterActivity"
        android:exported="false" />
    <!-- keep your existing MainActivity entry -->
</application>

Application code

Select a file to see its code and where it belongs.

This code uses package com.example.loginregistersqlite. Change that first line to your own package, the one at the top of your MainActivity.

Replace fileapp/src/main/java/com/example/loginregistersqlite/MainActivity.java

The login screen. Checks the username and password, then opens Home.

MainActivity.java

package com.example.loginregistersqlite;

import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

/** The login screen. Opens HomeActivity when the username and password match. */
public class MainActivity extends AppCompatActivity {
    EditText username, password;
    TextView signupText;
    Button loginButton;
    DatabaseHelper databaseHelper;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Screens.setUp(this, R.layout.activity_main);

        username = findViewById(R.id.userNameText);
        password = findViewById(R.id.passwordText);
        loginButton = findViewById(R.id.loginButton);
        signupText = findViewById(R.id.textSignup);
        databaseHelper = new DatabaseHelper(this);

        signupText.setOnClickListener(v -> startActivity(new Intent(this, RegisterActivity.class)));

        loginButton.setOnClickListener(v -> {
            String user = username.getText().toString().trim();
            String pass = password.getText().toString();
            if (user.isEmpty() || pass.isEmpty()) {
                Toast.makeText(this, R.string.error_empty, Toast.LENGTH_SHORT).show();
                return;
            }
            String loggedInUserName = databaseHelper.checkLogin(user, pass);
            if (loggedInUserName != null) {
                Intent intent = new Intent(this, HomeActivity.class);
                intent.putExtra("USERNAME", loggedInUserName);
                startActivity(intent);
                finish();
            } else {
                Toast.makeText(this, R.string.error_login, Toast.LENGTH_SHORT).show();
            }
        });
    }
}

Full source code

Download project ZIP View on GitHub