PunctuOwlity Android Source: Activities and Architecture

The Android version of PunctuOwlity is a Java app built with Android Studio, targeting API 35 with a minimum of API 21, using SQLite for local storage via a custom DatabaseHelper class and Material3 for theming. All business logic, navigation, and data persistence are handled inside the Activity layer — there are no Fragments, ViewModels, or repositories.

Project Structure

All source files live under the package com.example.punctuowlityeventtracker. The package contains seven classes in total:

Class	Role
`LoginActivity`	Launcher activity — username/password sign-in
`SignupActivity`	New-account registration
`SmsPermissionActivity`	Runtime `SEND_SMS` permission request
`MainActivity`	Main event list dashboard
`AddEventActivity`	Create or edit a single event
`DatabaseHelper`	SQLite `SQLiteOpenHelper` wrapper
`Event`	Plain data model for a single event row

Gradle highlights

android {
    namespace 'com.example.punctuowlityeventtracker'
    compileSdk 35

    defaultConfig {
        applicationId "com.example.punctuowlityeventtracker"
        minSdk 21
        targetSdk 35
        versionCode 1
        versionName "1.0"
    }
}

The project uses the Version Catalog (gradle/libs.versions.toml) to pin dependency versions. Java source and target compatibility are set to JavaVersion.VERSION_11.

Activity Reference

LoginActivity

Purpose: Entry point of the application. Accepts a username and password, validates them against the SQLite users table, and navigates to MainActivity on success. Layout: activity_login.xml Key UI elements:

editUsername (EditText) — username input
editPassword (EditText) — password input
buttonLogin (Button) — submits credentials
buttonSignUp (Button) — navigates to SignupActivity

Navigation:

Login button → calls DatabaseHelper.checkUser(username, password). On true, starts MainActivity and calls finish().
Sign Up button → starts SignupActivity.
A failed login shows a short Toast: "Invalid Username or Password".

buttonLogin.setOnClickListener(v -> {
    String username = editUsername.getText().toString().trim();
    String password = editPassword.getText().toString().trim();
    if (databaseHelper.checkUser(username, password)) {
        Intent intent = new Intent(LoginActivity.this, MainActivity.class);
        startActivity(intent);
        finish();
    } else {
        Toast.makeText(LoginActivity.this, "Invalid Username or Password",
                Toast.LENGTH_SHORT).show();
    }
});

SignupActivity

Purpose: New-account registration screen. Collects an email address (used as the username) plus a password with a confirmation check, then inserts the credentials into the SQLite users table. Layout: activity_signup.xml Key UI elements:

editEmail (EditText) — taken as the username stored in the database
editPassword (EditText) — desired password
editConfirmPassword (EditText) — password confirmation
buttonCreateAccount (Button) — triggers registration

Navigation:

Create Account button → validates that both password fields match, then calls DatabaseHelper.insertUser(username, password). On success, shows "Account Created Successfully" and redirects to LoginActivity. On failure (e.g. duplicate username), shows "Account creation failed!".

buttonCreateAccount.setOnClickListener(v -> {
    String username = editEmail.getText().toString().trim();
    String password = editPassword.getText().toString().trim();
    String confirmPassword = editConfirmPassword.getText().toString().trim();

    if (!password.equals(confirmPassword)) {
        Toast.makeText(SignupActivity.this, "Passwords do not match!",
                Toast.LENGTH_SHORT).show();
    } else {
        boolean success = databaseHelper.insertUser(username, password);
        if (success) {
            Toast.makeText(SignupActivity.this, "Account Created Successfully",
                    Toast.LENGTH_SHORT).show();
            startActivity(new Intent(SignupActivity.this, LoginActivity.class));
            finish();
        } else {
            Toast.makeText(SignupActivity.this, "Account creation failed!",
                    Toast.LENGTH_SHORT).show();
        }
    }
});

SmsPermissionActivity

Purpose: Displayed when MainActivity detects that the SEND_SMS permission has not been granted. Presents the user with an explicit Allow or Deny choice before proceeding to the main screen. Layout: activity_sms.xml Key UI elements:

buttonAllow (Button) — requests the SEND_SMS runtime permission via ActivityCompat.requestPermissions
buttonDeny (Button) — skips the permission request and proceeds directly

Navigation: Both buttons ultimately call goToMainActivity(), which starts MainActivity and finishes SmsPermissionActivity. If the Allow path triggers an OS permission dialog, onRequestPermissionsResult calls goToMainActivity() regardless of whether the user granted or denied.

private void goToMainActivity() {
    Intent intent = new Intent(SmsPermissionActivity.this, MainActivity.class);
    startActivity(intent);
    finish();
}

MainActivity

Purpose: The primary event list screen. Loads all events from SQLite into a GridLayout using inflated event_card views, and provides edit and delete actions per card. Layout: activity_main.xml Key UI elements:

eventsGrid (GridLayout) — host for dynamically inflated event_card views
fabAddEvent (Floating Action Button) — navigates to AddEventActivity for a new event

On create: Initialises DatabaseHelper, calls loadEvents(), wires the FAB, and checks whether SEND_SMS is granted. If not, immediately starts SmsPermissionActivity (without finishing MainActivity, so the back stack is preserved). loadEvents() method:

private void loadEvents() {
    eventsGrid.removeAllViews();
    ArrayList<Event> events = db.getAllEvents();

    for (Event event : events) {
        CardView card = (CardView) getLayoutInflater()
                .inflate(R.layout.event_card, eventsGrid, false);

        TextView textDay   = card.findViewById(R.id.tempTextDay);
        TextView textDate  = card.findViewById(R.id.tempTextDate);
        TextView eventTitle = card.findViewById(R.id.tempEventTitle);
        TextView textTime  = card.findViewById(R.id.tempTextTime);
        ImageButton buttonEdit   = card.findViewById(R.id.tempButtonEdit);
        ImageButton buttonDelete = card.findViewById(R.id.tempButtonDelete);

        textDay.setText(event.getDayOfWeek());  // e.g. "SAT"
        textDate.setText(event.getDateDay());   // e.g. "05"
        eventTitle.setText(event.getTitle());   // e.g. "Project Two Due"
        textTime.setText(event.getTime());      // e.g. "ALL DAY" or "01:30PM"

        buttonEdit.setOnClickListener(v -> {
            Intent intent = new Intent(MainActivity.this, AddEventActivity.class);
            intent.putExtra("event_id", event.getId());
            startActivity(intent);
        });

        buttonDelete.setOnClickListener(v -> {
            db.deleteEvent(event.getId());
            loadEvents();
            Toast.makeText(MainActivity.this, "Event Deleted",
                    Toast.LENGTH_SHORT).show();
        });

        eventsGrid.addView(card);
    }
}

loadEvents() is also called from onResume() so the list refreshes automatically after returning from AddEventActivity.

AddEventActivity

Purpose: Handles both creating a new event and editing an existing one. The caller signals edit mode by including an "event_id" Intent extra; without it the activity creates a new event. Layout: activity_add_event.xml Key UI elements:

editEventTitle (EditText) — event title
textEventDate (EditText) — event date (displayed/entered as text)
textEventTime (EditText) — event time (displayed/entered as text)
buttonSave (Button) — saves the event
imageButton (ImageButton) — back button, calls finish()

Save button logic:

buttonSave.setOnClickListener(v -> {
    String title = editEventTitle.getText().toString().trim();
    String date  = textEventDate.getText().toString().trim();
    String time  = textEventTime.getText().toString().trim();

    if (title.isEmpty() || date.isEmpty() || time.isEmpty()) {
        Toast.makeText(this, "All fields are required", Toast.LENGTH_SHORT).show();
    } else {
        if (eventId == -1) {
            db.insertEvent(title, date, time);
            Toast.makeText(this, "Event Added", Toast.LENGTH_SHORT).show();
        } else {
            db.updateEvent(eventId, title, date, time);
            Toast.makeText(this, "Event Updated", Toast.LENGTH_SHORT).show();
        }
        finish();
    }
});

When "event_id" is present in the incoming Intent, the activity calls db.getEventById(eventId) and pre-populates all three fields with the existing values.

Permissions and Manifest

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

    <!-- Permissions -->
    <uses-permission android:name="android.permission.SEND_SMS" />
    <uses-feature android:name="android.hardware.telephony" android:required="false" />

    <application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.PunctuOwlityEventTracker"
        tools:targetApi="31">

        <!-- Login Screen (launcher) -->
        <activity android:name=".LoginActivity" android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <!-- Sign Up Screen -->
        <activity android:name=".SignupActivity" android:exported="false" />

        <!-- SMS Permission Screen -->
        <activity android:name=".SmsPermissionActivity" android:exported="false" />

        <!-- Add Event Screen -->
        <activity
            android:name=".AddEventActivity"
            android:exported="false"
            android:label="Add Event"
            android:theme="@style/Theme.PunctuOwlityEventTracker" />

        <!-- Main Screen -->
        <activity android:name=".MainActivity" android:exported="false" />

        <!-- Preloaded Fonts -->
        <meta-data
            android:name="preloaded_fonts"
            android:resource="@array/preloaded_fonts" />

    </application>
</manifest>

android.hardware.telephony is declared with android:required="false" so that the app can be installed on tablets and emulators that do not have a cellular radio. The SEND_SMS permission is still declared and requested at runtime, but its absence does not prevent the app from running. Only LoginActivity is exported and set as the launcher entry point. All other activities are internal (android:exported="false").

Dependencies

Key runtime dependencies declared in build.gradle (versions resolved via gradle/libs.versions.toml):

Artifact	Version	Purpose
`androidx.appcompat:appcompat`	1.7.0	`AppCompatActivity` base class for all activities
`com.google.android.material:material`	1.12.0	Material Design widgets (buttons, cards, FAB)
`androidx.activity:activity`	1.8.0	`ComponentActivity` and result APIs
`androidx.constraintlayout:constraintlayout`	2.1.4	Constraint-based layouts
`androidx.gridlayout:gridlayout`	1.1.0	`GridLayout` used in `MainActivity` for the event grid
`androidx.legacy:legacy-support-v4`	1.0.0	Backward-compatibility utilities
`androidx.lifecycle:lifecycle-runtime-ktx`	2.8.7	Lifecycle-aware coroutine scopes
`androidx.compose.material3:material3`	(BOM 2024.09.00)	Material3 theming tokens via Compose BOM

Get Started

Using PunctuOwlity

Technical Reference

Resources

PunctuOwlity Android Source: Activities and Architecture

Project Structure

Gradle highlights

Activity Reference

LoginActivity

SignupActivity

SmsPermissionActivity

MainActivity

AddEventActivity

Permissions and Manifest

Dependencies

Build docs developers (and LLMs) love

Get Started

Using PunctuOwlity

Technical Reference

Resources

Documentation Index

​Project Structure

​Gradle highlights

​Activity Reference

​LoginActivity

​SignupActivity

​SmsPermissionActivity

​MainActivity

​AddEventActivity

​Permissions and Manifest

​Dependencies

Build docs developers (and LLMs) love

Project Structure

Gradle highlights

Activity Reference

LoginActivity

SignupActivity

SmsPermissionActivity

MainActivity

AddEventActivity

Permissions and Manifest

Dependencies