chatrtc/android-app

ChatRTC - Android WebRTC Chat Application

A modern Android chat application with WebRTC support for audio/video calling and emoji text messaging.

Features

• Nickname-based joining: Users only need to enter their nickname to join the chat
• Text messaging with emoji support: Full emoji keyboard and rendering support
• Audio/Video calling: WebRTC-powered audio and video communication
• Modern UI: Material Design components with beautiful chat bubbles
• Camera controls: Toggle video, mute audio, and switch between front/back cameras
• Real-time communication: Instant messaging and WebRTC peer-to-peer connections

Project Structure

chatrtc/
├── app/                          # Android application
│   ├── src/main/java/com/chatrtc/app/
│   │   ├── MainActivity.java     # Nickname entry screen
│   │   ├── ChatActivity.java     # Main chat interface
│   │   ├── adapter/
│   │   │   └── ChatAdapter.java  # RecyclerView adapter for messages
│   │   ├── model/
│   │   │   └── ChatMessage.java  # Message data model
│   │   └── webrtc/
│   │       └── WebRTCManager.java # WebRTC connection management
│   └── src/main/res/             # Android resources
└── signaling-server/             # Node.js signaling server
    ├── server.js                 # Socket.IO signaling server
    └── package.json              # Server dependencies

Setup Instructions

1. Android App Setup

1. Prerequisites:

   • Android Studio Arctic Fox or later
   • JDK 8 or later
   • Android SDK API 24+ (Android 7.0)

2. Open the project:

   cd chatrtc
   # Open in Android Studio
   

3. Configure signaling server URL:

   • Open app/src/main/java/com/chatrtc/app/webrtc/WebRTCManager.java
   • Update the SIGNALING_SERVER_URL constant with your server URL:

   private static final String SIGNALING_SERVER_URL = "https://your-server.com";
   // For local development: "http://10.0.2.2:3000"
   

4. Build and run:

   • Connect your Android device or start an emulator
   • Click "Run" in Android Studio

2. Signaling Server Setup

1. Install Node.js: Download from nodejs.org

2. Install dependencies:

   cd signaling-server
   npm install
   

3. Start the server:

   npm start
   # or for development with auto-restart:
   npm run dev
   

4. Server will run on: http://localhost:3000

Usage

1. Start the signaling server (see setup instructions above)
2. Install and run the Android app on your device(s)
3. Enter your nickname on the welcome screen
4. Grant permissions for camera and microphone when prompted
5. Start chatting:
   • Send text messages with emoji support
   • Toggle video/audio using the control buttons
   • Switch cameras using the camera switch button
   • Multiple users can join the same chat room

Key Components

Android App

• MainActivity: Handles nickname entry and permissions
• ChatActivity: Main chat interface with video views and message list
• WebRTCManager: Manages WebRTC connections, media streams, and signaling
• ChatAdapter: Handles different message types (own, other, system)
• Emoji Support: Uses Vanniktech emoji library for full emoji rendering

WebRTC Features

• Peer-to-peer connections: Direct audio/video streams between users
• Data channels: For text message transmission
• STUN servers: Google's STUN servers for NAT traversal
• Camera management: Front/back camera switching
• Media controls: Toggle audio/video streams

Signaling Server

• Socket.IO based: Real-time bidirectional communication
• Room management: Users join a common chat room
• WebRTC signaling: Handles offer/answer/ICE candidate exchange
• User management: Tracks connected users and broadcasts join/leave events

Dependencies

Android

• WebRTC: org.webrtc:google-webrtc:1.0.32006
• Socket.IO: io.socket:socket.io-client:2.0.1
• Emoji Support: com.vanniktech:emoji-google:0.16.0
• Material Design: com.google.android.material:material:1.9.0

Server

• Express: Web server framework
• Socket.IO: Real-time communication
• CORS: Cross-origin resource sharing

Network Configuration

For local development, the app includes network security configuration to allow HTTP connections to localhost and common local IP addresses.

Permissions

The app requires:

• CAMERA: For video calling
• RECORD_AUDIO: For audio calling
• MODIFY_AUDIO_SETTINGS: For audio management
• INTERNET: For signaling server connection
• ACCESS_NETWORK_STATE: For network status

Deployment

Android App

• Build APK: ./gradlew assembleDebug
• Install: adb install app/build/outputs/apk/debug/app-debug.apk

Signaling Server

• Deploy to any Node.js hosting service (Heroku, Railway, etc.)
• Update the SIGNALING_SERVER_URL in the Android app
• Ensure HTTPS is used for production (required by WebRTC)

Troubleshooting

1. Connection issues: Check signaling server URL and network connectivity
2. Permission errors: Ensure camera/microphone permissions are granted
3. Video not showing: Check camera availability and permissions
4. Audio not working: Verify microphone permissions and device audio settings

Contributing

1. Fork the repository
2. Create your feature branch
3. Commit your changes
4. Push to the branch
5. Create a Pull Request

License

This project is open source and available under the MIT License.