Building a full-featured chat application for Android from scratch presents numerous complex challenges that developers must overcome:
Setting up real-time infrastructure for message exchanges
Managing message delivery and storage
Implementing user authentication
Scaling for multiple users and heavy usage
Designing an intuitive and functional chat interface
Implementing push notifications
CometChat's Android UI Kit simplifies this process by providing pre-built, customizable chat components that handle these complexities while giving developers the flexibility to create a unique chat experience that aligns with their app's requirements.
To illustrate how CometChat accelerates your Android chat development process, here's a detailed comparison between building a chat app using traditional methods versus leveraging CometChat:
Feature/Component | DIY Approach | With CometChat |
---|---|---|
Setup Time
| 3-4 weeks for basic features
| 2-3 days for full implementation
|
Backend Infrastructure
| Build and maintain custom servers, databases, and WebSocket connections. Handle data synchronization across devices.
| Fully managed by CometChat. Scalable infrastructure with automatic synchronization.
|
Real-time Communication
| Implement complex WebSocket handling, connection management.
| Built into SDK with automatic handling of Android lifecycle events and background states
|
User Management
| Create user systems, implement presence tracking, manage token-based authentication
| Pre-built user management system with presence handling and secure authentication
|
Message Delivery
| Build queuing systems, implement retry logic, handle offline messages, manage Android service limitations
| Automatic with guaranteed delivery and offline support
|
Media Handling
| Implement file compression, handle Android storage permissions, manage upload/download states
| Built-in media handling with automatic permission management and efficient caching
|
Push Notifications
| Set up FCM, handle token management, implement notification channels, manage background/foreground states
| Ready-to-use FCM integration with customizable notification settings
|
Security
| Implement encryption, manage secure storage, handle Android keystore
| Enterprise-grade security with automatic encryption handling
|
UI Components
| Build custom Android layouts, implement Material Design, handle different screen sizes
| Pre-built, customizable Material Design components
|
Performance
| Handle memory management, implement efficient recycling, optimize battery usage
| Optimized components with automatic memory management
|
In this tutorial, we'll build a feature-rich Android chat application that includes:
One-on-one and group messaging
Rich media sharing
Message threads and reactions
Real-time presence and typing indicators
Push notifications using Firebase Cloud Messaging (FCM)
Customizable UI components
Prerequisites
Before starting this tutorial, make sure you have:
Android Studio installed (latest version)
Basic knowledge of Android development with Kotlin
Firebase project set up for push notifications
Android device or emulator with Android version 6.0 or above
Android 5.0 (API level 21) or higher
Java 8 or higher
Android Gradle plugin 4.0.1 or higher
CometChat account (free plan available)
Getting Started
Step 1. Create new android project
First, create a new Android project:
Open Android Studio
Select "Create New Project"
Choose "Empty Activity"
Set application name as "AndroidChatApp"
Select minimum SDK level (API 21 or higher)
Choose Kotlin as the programming language
Step 2. Configure dependencies
Open your project-level settings.gradle file and add:
In your app-level build.gradle, configure CometChat credentials and add dependencies:
To obtain your CometChat app credentials, follow these steps:
Sign Up for a CometChat Account from here.
Once signed in, go to your dashboard and create a new app.
After creating the app, locate and copy the following credentials: App ID, Auth Key and Region.
Update your gradle.properties:
Step 3. Configure android manifest
Open AndroidManifest.xml and add the required permissions:
Basic permissions (Required):
INTERNET: For chat communication
ACCESS_NETWORK_STATE: For network connectivity monitoring
Media permissions (Optional):
Storage permissions for handling media files.
Camera and audio permissions for media capture
New Android 13+ media permissions for granular access
Step 4. Initialize CometChat
Create an Application class for proper initialization:
Step 5. Add the application class to your manifest
Building the chat app interface
1. User login and authentication flow
Before diving into building the chat interface, we'll create a login component that authenticates users with CometChat using their unique User ID. We'll create a login component that:
Accepts a User ID input from the user
Authenticates the User ID against CometChat's backend
Handles loading states and error messages
Establishes a user session upon successful login
Step 1: Create the Login Activity
First, we'll create the login activity that will handle user authentication. This activity will:
Check for existing sessions
Handle user input
Manage the authentication process
Navigate to the chat interface upon successful login
Step 2: Designing the Login Screen
Next, we'll create a clean, simple login interface. The layout includes:
A text field for the user ID
A login button
Loading and error indicators to keep users informed of what's happening
Step 3: Update the Application Class
To handle user sessions effectively, we'll update our Application class to:
Initialize CometChat when the app starts
Track authentication state
Provide logout functionality
Finally, we'll update the manifest to make the login screen our app's entry point. This ensures users see the login screen first unless they're already authenticated
Step 4: Configuring Build Settings
Before we can use CometChat's authentication features and ViewBinding, we need to update our build configuration. These settings enable:
View binding for easier UI handling
BuildConfig fields for secure credential storage
Kotlin optimizations for better performance
2. Building the Chat Interface
After successfully implementing user authentication, we'll now create the main chat interface where users can view conversations and exchange messages. This section demonstrates how to integrate CometChat's UI components into your Android app.
For messaging-focused apps like WhatsApp or Telegram, this interface serves as the main screen where users land after logging in. For apps where chat is a supplementary feature, it functions as the messaging inbox.
The chat interface consists of two primary components:
Conversation List: Shows recent chats and their latest messages
Message screen: Provides the messaging interface with features like: Message composition and sending, Real-time message delivery, Read receipts, Typing indicators, Media sharing
To simplify development, we'll use the CometChatConversationsWithMessages component from CometChat's Android UI Kit. This component offers a complete chat interface with all essential features through a single implementation.
Understanding CometChatConversationsWithMessages
The CometChatConversationsWithMessages component is a powerful, all-in-one solution that combines everything you need for a full-featured chat interface. This single component includes:
1. Conversation Management
Complete conversation list
Real-time updates for new messages
Unread message indicators
Last message previews
Timestamp displays
Automatic conversation sorting
2. Messaging Interface
Message composition and sending
Rich media messaging (images, videos, files)
Message reactions
Message threads and replies
Link previews
@mentions support
Real-time message delivery
Read receipts
Typing indicators
3. User Presence Features
Online/offline status
Last seen timestamps
Typing indicators
Read receipts
User avatars
All these features come pre-built and require no additional configuration. Let's implement this comprehensive chat interface:
Implementing the Chat Interface
First, let's create the layout for our main chat screen:
Next, implement the MainActivity that will host our chat interface:
This implementation follows a straightforward flow:
When MainActivity launches, it verifies the user's authentication status
For authenticated users: Displays the chat interface with conversations and messages. Automatically handles real-time message updates.
For unauthenticated users: Redirects to the login screen and prevents access to chat functionality
Adding advanced functionalities on top of the existing features
1. Setting up notifications
Now that your chat functionality is up and running, it's time to enable notifications so users never miss a message. CometChat’s Notifications module allows you to set up and manage notifications across multiple providers directly from the dashboard, ensuring centralized control and effortless configuration. You can easily integrate push notifications with APNs and FCM, email notifications with SendGrid, and SMS alerts with Twilio, or use webhooks to connect with any provider of your choice.
You can also enable notification preferences for your users, allowing them to customize when and how they receive notifications. Additionally, our customizable templates let you tailor notifications to your app’s tone and branding.
2. Setting up advanced moderation
Next, we’ll explore CometChat’s powerful moderation capabilities, which you can enable using the CometChat SDK. These features are designed to help maintain a safe, respectful environment for users and allow you to moderate content in real time.
Front-end moderation
User reporting: Empower your users to report inappropriate behavior or content directly from the chat interface.
User blocking: Allow users to block others, preventing unwanted interactions.
Message flagging: Enables users to flag specific messages for review by administrators.
Moderation queue:
Use our centralized moderation dashboard to give app admins an organized view of flagged messages, reported users, and blocked content. From this dashboard, admins can take real-time action on flagged content, issue user bans or warnings, and escalate issues for higher-level review, all in one place.
Proactive content moderation:
Use our advanced AI filters to prevent harmful content from entering your chat. These filters automatically screen every message exchanged in your app for violations defined by you and take action based on the moderation rules you’ve set up with our rules engine.
CometChat’s rules engine lets you create custom rules to address common moderation scenarios. You can define which filters to use for identifying violations and specify how to handle them, such as blocking a user or removing them from a group. This helps you keep your app free from:
Spam: Block unwanted or malicious content.
Harassment: Automatically filter harmful messages or behavior.
Image and Video Moderation: Analyze and filter media content to ensure it follows guidelines
3. Using Webhooks to extend your chat app's functionality
Leverage webhooks to trigger actions based on key events like message exchanges, user interactions, group changes, and call activities. You can use them to automate tasks, integrate with external services, and optimize the chat experience in your app. You can configure these webhooks directly from the CometChat dashboard.
Here’s a list of available webhooks:
Category | Webhook Event |
---|---|
Message
| Message Sent, Edited, Deleted, Reacted, Mentioned, Delivered, Read
|
User
| User Blocked, Unblocked, Connection Status Changed
|
Group
| Group Created, Member Added, Member Left, Group Owner Changed, Member Kicked
|
Calling
| Call Started, Call Ended, Call Initiated, Participant Joined, Participant Left, Call Recording Generated
|
Customizing your android chat app : Theme, fonts and component appearance
After implementing the chat interface, you might want to customize its appearance to match your app's design. CometChat's UI Kit provides simple ways to customize the look and feel through its theming system.
1. Theme-level Customization
CometChat's theme system consists of two main components:
Palette: Controls colors throughout the app
Typography: Manages text styles
Color customization
You can easily customize the color scheme using the Palette class:
Set primary color for main elements
Set accent color for interactive elements
Test in both light and dark modes
Text style customization
The typography class gives you full control over your app's text appearance.
Choose fonts that complement your app's identity.
Define bold, medium, and regular weights for emphasis.
Customize titles, subtitles, and captions for clear hierarchy and readability.
2. Component-level customisation
In addition to theme customization, CometChat allows for in-depth customization of individual components within its UI Kits. This enables you to tailor the appearance and behavior of specific elements to suit your application’s needs.
In this section, we'll focus on customizing two essential components that form the backbone of our chat interface: the Conversations and Messages components. We'll explore the various customization options available for these components, demonstrate how to implement them effectively, and walk through the different parameters you can modify to create a tailored chat experience.
Conversations component customisation
The Conversations component displays all conversations related to the currently logged-in user. To ensure the component aligns with your app's design and branding, you can easily customize its appearance by adjusting the properties exposed by the ConversationsStyle class. Below, you'll find a table outlining all the properties you can modify to tailor the component to your specific needs.
Category | Customizable Elements | Description |
---|---|---|
Layout & Appearance
| List Item View
| Height, width, background colors, hover states
|
Layout & Appearance
| Avatar Display
| Shape, size, border radius, default icons
|
Layout & Appearance
| Status Indicators
| Size, color, position, visibility
|
Content Display
| Conversation Title
| Font style, size, color, formatting
|
Content Display
| Last Message Preview
| Length, style, condensed view options
|
Content Display
| Timestamps
| Format, position, localization
|
Interactive Elements
| Search Bar
| Visibility, placeholder text, icon customization
|
Interactive Elements
| Selection Mode
| Single/multi select, selection indicators
|
Interactive Elements
| Empty States
| Custom messages, actions, layouts
|
For more advanced customization, you can define custom views within the Conversations component. This allows you to fully control and tailor each element of the interface, such as layouts, views, and UI elements, ensuring that the component perfectly matches your app's overall aesthetics and functionality. .
Messages component customization
The Messages component is a central feature of our chat interface, responsible for rendering the area where messages are exchanged between users and groups. It plays a key role in managing the real-time flow of messages within the app. Below, you'll find a table outlining all the properties you can modify to tailor the messages component to your specific needs
Category | Customizable Elements | Description |
---|---|---|
Message Bubbles
| Layout
| Size, shape, padding, margins
|
Message Bubbles
| Styling
| Colors, borders, shadows
|
Message Bubbles
| Alignment
| Left/right positioning, spacing
|
Message Types
| Text Messages
| Font styles, sizes, colors
|
Message Types
| Media Messages
| Preview size, player controls
|
Message Types
| Link Previews
| Size, layout, information display
|
Interactive Features
| Reactions
| Position, size, layout
|
Interactive Features
| Thread Replies
| Thread view, indicators
|
Interactive Features
| Message Actions
| Custom actions, menus
|
Metadata Display
| Timestamps
| Format, position
|
Metadata Display
| Read Receipts
| Style, position, indicators
|
Metadata Display
| Typing Indicators
| Animation, position
|
Testing and deploying Your Chat App
Now that you've built your Android chat app with CometChat, let's ensure everything works correctly before deployment.
Testing user authentication
Testing Chat Functionality
To test your chat implementation:
Login with "cometchat-uid-1" on one device
Login with "cometchat-uid-2" on another device/emulator
Test chat features between these users:
Send and receive messages
Verify real-time delivery
Check conversation updates
Test media sharing if implemented
Pre-deployment Checklist and Deployment
Configuration Verification
Release Configuration
Add to your app-level build.gradle
Verify essential permissions
Verify AndroidManifest.xml:
Deploy the app
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Haris Kumar
Lead Content Strategist , CometChat