Audio-Recorder-App

This is an audio recorder application developed in Flutter (Dart) which may be deployed to Android.

Features

• Record high quality audio
• Quick record with long press
• Pause and resume recording
• Record in various file formats (.mp3, .wav, .m4a)
• Record in various sampling rates (16kHz, 44.1kHz, 48kHz) - TODO (currently only 128kbps supported)
• Play last recording easily in one-tap
• View all previous recordings
• Play any of the recording
• Smooth animations and haptic feedback
• Visualise amplitude in real-time

Permissions

Kai requires only these three permissions:

• [INTERNET] To access the internet for downloading the fonts (Rubik from Google Fonts). App works without internet too.
• [MICROPHONE] To record audio (needed).
• [WRITE_EXTERNAL_STORAGE] To save the audio file, app accesses application documents folder and no other folder is visible (Scoped storage), works if denied too.

Built With

• Flutter
• Dart

Getting Started

To build, please follow these steps.

Step 1:

git clone https://github.com/nirobio/audio-recorder-app.git

Step 2:

Follow the instructions here to install Android Studio. Then you're ready to build the app.

For testing the app you can create an emulator following the steps here, or directly run on a physical Android device.

Step 3:

Follow the instructions here to install Flutter. As Odin uses the stable channel, you need to switch the channel if you are on dev or beta channels. Just type:

flutter channel stable

Step 4:

You should generate the necessary code first.

flutter pub run build_runner build --delete-conflicting-outputs

Step 5:

To run the app just type these commands in terminal or use the Run and Debug option from your editor of choice.

flutter pub get
flutter run

Folder Structure

The folder structure is explained below.

lib (All flutter code in present here)
 ┃
 ┣ constants (Various constant values used throughout the app)
 ┃
 ┣ controllers (All the controllers/notifiers used in the app)
 ┃
 ┣ pages (All the UI pages in the app)
 ┃
 ┣ painters (All the custom painters used in the app)
 ┃
 ┣ router (All the routes used in the app)
 ┃
 ┣ services (All the services used in the app)
 ┃
 ┣ utils (All reusable code (functions, classes, etc.) used in the app)
 ┃
 ┗ widgets (All the widgets used in the app)

lib
 ┃
 ┣ constants
 ┃ ┣ app_color.dart (App color constants)
 ┃ ┗ app_data.dart (App data constants such as device size)
 ┃
 ┣ controllers
 ┃ ┣ audio_player_controller.dart (Audio player controller)
 ┃ ┣ path_controller.dart (Path controller)
 ┃ ┣ record_controller.dart (Recording controller)
 ┃ ┣ settings_controller.dart (Settings controller)
 ┃ ┣ theme_controller.dart (Theme controller)
 ┃ ┣ timer_controller.dart (Timer controller to check recording duration)
 ┃ ┗ waveform_controller.dart (Waveform controller, to plot amplitude waveform)
 ┃
 ┣ pages
 ┃ ┣ home_page.dart (The default home page, which consists of app bar and body)
 ┃ ┣ loading_page.dart (A loading page is shown for data loading)
 ┃ ┗ record_page.dart (The main body of the app, which consists of recording, playback, and settings)
 ┃
 ┣ painters
 ┃ ┣ audio_waveform_painter.dart (Painter to draw the waveform, not in use)
 ┃ ┣ ripple_painter.dart (Painter to draw the ripple effect behind record button)
 ┃ ┗ wave_painter.dart (Painter to draw the waveform of the amplitude + animations)
 ┃
 ┣ router
 ┃ ┣ app_router.dart (Define routes inside the app)
 ┃ ┣ app_router.gr.dart (Generated file)
 ┃ ┣ route_observer.dart (Define route observer to get current route stack, and debug)
 ┃ ┗ transition_route_builders.dart (Animations which happen on route transition)
 ┃
 ┣ services
 ┃ ┣ locator.dart (Service locator, using get_it package to register notifiers and services)
 ┃ ┣ logger.dart (Logger service, which logs errors, infos or any warnings)
 ┃ ┣ product_service.dart (Product service, which handles all product related operations like fetching them)
 ┃ ┣ theme_pref_service.dart (Theme preference service, which handles the theme preference, and change theme)
 ┃ ┣ theme_service.dart (Theme service, which handles the theme, and change theme)
 ┃ ┗ transaction_service.dart (Transaction service, which handles all stock record related operations like fetching, updating them)
 ┃ ┣ audio_player_service.dart
 ┃ ┣ locator_service.dart (Service locator, using get_it package to register notifiers and services)
 ┃ ┣ logger_service.dart (Logger service, which logs errors, infos or any warnings)
 ┃ ┣ path_service.dart (Path service, which handles all path related operations like fetching docs, etc.)
 ┃ ┣ record_service.dart (Recording service, which handles all recording related operations)
 ┃ ┣ settings_service.dart (Settings service, which handles all settings, currently handles only graph style)
 ┃ ┣ snackbar_service.dart (Snackbar service, which handles all snackbars)
 ┃ ┣ theme_pref_service.dart (Theme preference service, which handles the theme preference, and change theme)
 ┃ ┣ theme_service.dart (Theme service, which handles the theme, and change theme)
 ┃ ┣ timer_service.dart (Timer service, which handles all timers which are used for recording duration, amplitude waveform, etc.)
 ┃ ┗ waveform_service.dart (Waveform service, which handles all waveform related operations, currently not in use)
 ┃
 ┣ utils
 ┃ ┗ smoothing.dart (A filter to smooth out the amplitude waveform matrix)
 ┃
 ┣ widgets
 ┃ ┣ amplitude_widget.dart (Widget to draw the amplitude waveform)
 ┃ ┣ audio_waveform_widget.dart (Widget to draw the waveform, not in use)
 ┃ ┣ bug_report_button.dart (Button to send bug reports)
 ┃ ┣ directory_button.dart (Widget to display the directory button)
 ┃ ┣ directory_sheet.dart (Widget to display the directory sheet)
 ┃ ┣ format_settings.dart (Widget to display the format settings)
 ┃ ┣ last_recording_bubble.dart (Widget to display the last recording bubble)
 ┃ ┣ pause_button.dart (Widget to display the pause button)
 ┃ ┣ realistic_graph_button.dart (Widget to display the realistic graph button)
 ┃ ┣ recording_card.dart (Widget to display the recording card in directory sheet)
 ┃ ┣ record_button.dart (Widget to display the record button)
 ┃ ┣ record_duration.dart (Widget to display the recording duration)
 ┃ ┗ scrollable_bottom_sheet.dart (Widget to display the bottom sheet i.e. used in directory sheet)
 ┃
 ┣ generated_plugin_registrant.dart (Generated file for plugins)
 ┗ main.dart (Main file, which is the entry point of the app, used for registering theme, providers, routes, etc.)

Packages Used

All the different packages used throughout the app, with thier explanations.

• animations: ^2.0.2 - Used for animations during page/route transitions
• auto_route: ^3.2.0 - Used to generate routes automatically
• device_info_plus: ^3.2.0 - Used to get device info for bug reports
• flex_color_scheme: ^4.1.1 - Used for theming
• flutter_archive: ^4.1.0 - Used for creating zip file for logs
• flutter_mailer: ^2.0.1 - Used for sending bug reports via email
• get_it: ^7.2.0 - Used for state management
• google_fonts: ^2.1.0 - Used for Rubik font
• intl: ^0.17.0 - Used to format date and time
• just_audio: ^0.9.18 - Used to play audio recordings
• just_waveform: ^0.0.1 - Used to show audio waveform
• linalg: ^0.4.0 - Used to solve matrix for smoothing filter
• logger: ^1.1.0 - Used to log errors, info or warnings
• path_provider: ^2.0.8 - Used to get application directory path to save audio files
• provider: ^6.0.1 - Used for state management
• record: ^3.0.2 - Used to record and save audio
• rxdart: ^0.27.3 - Used to create streams
• shared_preferences: ^2.0.11 - Used to save theme preference
• sprung: ^3.0.0 - Usedd for dampening the animations

Dev dependencies -

• auto_route_generator: ^3.1.0 - Used for generating routes
• build_runner: ^2.1.7 - Used to generate necessary code