Introduction to an iOS Template App Using Clean Architecture and MVVM
The iOS-Clean-Architecture-MVVM project represents a structured approach to developing iOS applications by implementing the Clean Architecture pattern alongside the Model-View-ViewModel (MVVM) design. This template serves as an excellent starting point for developers looking to build robust iOS apps with a maintainable code structure.
Main Components of the Project
Architecture Layers
This project is divided into three primary layers, each with distinct responsibilities:
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Domain Layer: This layer is dedicated to business logic and consists of:
- Entities: Core business objects.
- Use Cases: Specific operations or business rules.
- Repositories Interfaces: Abstraction for handling data transactions.
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Data Repositories Layer: This is where the data handling takes place:
- Repositories Implementations: Concrete implementations of data operations.
- API (Network) Integration: Facilitates network communication to fetch and send data.
- Persistence DB: Handles local data storage.
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Presentation Layer (MVVM): The user interface layer, organized as:
- ViewModels: Encapsulate the presentation logic, maintaining the state of the UI.
- Views: The visual representation, either using UIKit or SwiftUI.
Dependency Direction
The layering approach ensures that dependencies flow towards the domain, keeping business logic isolated from the presentation and data layers.
Key Architectural Concepts
- Clean Architecture: Aligns with Uncle Bob's principle to separate software elements by responsibility to enhance flexibility and maintainability.
- Advanced iOS App Architecture: Incorporates best practices for more granular and efficient app design.
- MVVM: Provides clear separation between UI and business logic.
- Data Binding: Utilizes Observables for data binding without heavy third-party dependencies.
- Dependency Injection: Manages object creation and linking.
- Flow Coordinator: Orchestrates navigation and flow within the app.
- Data Transfer Object (DTO): Facilitates efficient data transfer.
- Response Data Caching: Improves performance by storing recent data responses.
- Lifecycle Behavior Handling: Manages UI component lifecycle events.
- SwiftUI and UIKit: Demonstrates view construction using both SwiftUI and UIKit while leveraging the same ViewModel.
- Error Handling: Demonstrates comprehensive strategies for managing errors across various layers.
Features
- Pagination: Efficiently loads lists of data.
- Unit Testing: Comprehensive testing coverage for use cases, ViewModels, and network services.
- Dark Mode Compatibility: Supports dark mode aesthetics.
- Adaptive UI: Utilizes size classes and UIStackView for responsive layouts.
- SwiftUI Example: Demonstrates how the presentation layer can remain unchanged as UI implementation shifts.
Networking and Reusability
The project's networking capabilities can be reused in other projects, further fostering modularity. An additional repository is available that offers similar functionality with all views constructed programmatically, featuring a UITableViewDiffableDataSource.
User Interaction
To use the app, users can search for movies by entering a title in the search bar. The application makes network requests to retrieve movie data as well as relevant poster images. Each successful search query is persistently saved for easy access.
Requirements
- Requires Xcode Version 11.2.1 or higher.
- Built using Swift 5.0 or later.
This project not only provides a solid foundation for developing iOS applications but also demonstrates industry best practices in software architecture. By adhering to the principles of Clean Architecture and MVVM, developers can ensure their applications are scalable, maintainable, and efficient.