Mortar + Flow with third party libraries hooked to activity lifecycle

Mortar + Flow with Third-Party Libraries

This article explores the integration of third-party libraries into the Mortar and Flow framework, emphasizing the seamless integration with the activity lifecycle. We’ll delve into the mechanisms that ensure proper library initialization and data management.

Overview

Mortar and Flow provide a robust architecture for structuring Android applications. This approach promotes cleaner code, better testability, and streamlined management of UI state. Let’s examine how to integrate third-party libraries effectively within this framework.

Integration Strategies

1. Dependency Injection (DI)

DI is a powerful technique to decouple components and enhance testability. In Mortar + Flow, Dagger 2, a popular DI library, is often used for dependency injection.

Using Dagger 2:

• Define your library dependencies in a Dagger module.
• Use Dagger to inject these dependencies into your Flow screens and components.

2. Activity Lifecycle Management

Mortar handles activity lifecycle events through the MortarScope. Here’s how to ensure libraries interact correctly:

a. Initializing Libraries

• Initialize libraries within the onCreate method of the activity’s MortarScope.
• Ensure initialization happens only once by using a singleton pattern or a custom Provider in Dagger 2.

b. Cleaning Up Libraries

• Implement the necessary cleanup procedures within the onDestroy method of the activity’s MortarScope.
• Release resources, deregister listeners, and handle any library-specific cleanup tasks.

3. Handling Configuration Changes

Mortar manages configuration changes, such as screen rotations. Libraries should be aware of these changes and be properly handled.

• Ensure libraries retain their state during configuration changes using serialization or persistence mechanisms.
• For complex libraries, implement custom onSaveInstanceState and onRestoreInstanceState methods in your MortarScope.

Example: Integrating a Network Library

Code:

// Dagger Module
@Module
public class NetworkModule {
  @Provides
  public NetworkService provideNetworkService() {
    return new Retrofit.Builder()
        .baseUrl("https://api.example.com/")
        .build()
        .create(NetworkService.class);
  }
}

// Screen
public class HomeScreen extends MortarScreen {
  @Override
  protected Component createComponent(Context context) {
    return Mortar.create(context, new Component());
  }

  public static class Component extends MortarScope.Component {
    @Provides
    public NetworkService networkService(NetworkModule networkModule) {
      return networkModule.provideNetworkService();
    }
  }
}

Explanation:

• The NetworkModule provides the NetworkService instance using Retrofit.
• The HomeScreen‘s Component injects the NetworkService using Dagger.
• The NetworkService is now accessible within the HomeScreen‘s View and Presenter.

Comparison: Mortar + Flow vs. Traditional Android Development

Conclusion

Mortar + Flow offers a powerful and efficient way to integrate third-party libraries into Android applications. By leveraging dependency injection, managing lifecycle events appropriately, and handling configuration changes effectively, developers can build robust and maintainable apps. This approach allows for cleaner, testable code, while ensuring smooth integration with libraries.