Why I Chose Coordinator Pattern While Developing a Modular SuperApp? ????

Lately, I have been working on developing a modular SuperApp. As the project grew, managing screen transitions and navigation logic became more complex.

At first, I used SwiftUI’s built-in NavigationLink, @State, @EnvironmentObject, and NavigationStack. However, I soon realized that, given the independent nature of SuperApp modules, each module needed to manage its own navigation flow.

SuperApp Structure:

? Education Module (Education)

? Health Module (Health)

? Travel Module (Travel)

? Visa Module (Visa)

? Events Module (Events)

? Meetup Module (Meetup)

Each module has different screens and navigation rules. For example:

? The Education Module navigates to a course detail page.

? The Visa Module needs a multi-step application process.

?? So, what’s the best way to handle navigation in such a large-scale app?

Since traditional SwiftUI navigation methods weren’t scalable, I decided to use the Coordinator Pattern. ??

?? What is the Coordinator Pattern?

The Coordinator Pattern is an architectural pattern that separates UI from navigation logic, making the navigation flow more manageable and modular.

Although this pattern has been widely used in UIKit, integrating it into SwiftUI’s declarative architecture initially seemed challenging. However, for large-scale projects, it simplifies navigation management significantly.

Key Advantages:

?? Navigation logic and UI are decoupled.

?? Each module has its own coordinator to manage its navigation flow.

?? Views (Screens) remain unaware of navigation logic.

?? Problems with Traditional Navigation Methods

1?? Using NavigationLink

? Every screen is responsible for handling its own navigation.

? Not flexible for complex navigation flows.

2?? Using @EnvironmentObject for Navigation Management

? A global state object can become too large.

? Inter-module navigation becomes hard to manage.

?? As projects scale, the codebase becomes harder to maintain and test.

?? How the Coordinator Pattern Manages Navigation

With Coordinator Pattern, each module has an independent class that handles its own navigation.

?? Example: Coordinator for the Education Module

import SwiftUI

class EducationCoordinator: ObservableObject {
    @Published var path = NavigationPath()

    func navigateToCourseDetail(courseID: String) {
        path.append(courseID)
    }

    func popToRoot() {
        path = NavigationPath()
    }

    func popLast() {
        path.removeLast()
    }
}        

This EducationCoordinator is responsible for managing navigation within the Education Module.

Now, let’s integrate it with SwiftUI’s view:

struct EducationView: View {
    @StateObject var coordinator = EducationCoordinator()
    
    var body: some View {
        NavigationStack(path: $coordinator.path) {
            VStack {
                Text("Education Module")
                    .font(.largeTitle)
                
                Button("Go to Course Detail") {
                    coordinator.navigateToCourseDetail(courseID: "swiftui-101")
                }
            }
            .navigationDestination(for: String.self) { courseID in
                CourseDetailView(courseID: courseID)
            }
        }
    }
}        

Here’s what happens:

? EducationCoordinator manages navigation separately.

? View (Education Module Home) is only responsible for UI.

? Navigation is managed centrally, making the architecture more scalable.

?? Coordinator Pattern Architecture

To visualize this concept, here’s a Coordinator-based navigation flow diagram:

? The App handles all modules.

? Each module has its own coordinator.

? Coordinators manage the navigation within their module.

This architecture allows for independent modules, making the app more scalable and maintainable.

? NavigationLink vs. Coordinator Pattern (Comparison Table)

?? Coordinator Pattern provides better modularity, testability, and maintainability for large-scale apps!

?? Conclusion

If you’re developing a large, multi-module SwiftUI app, using the Coordinator Pattern can:

? Provide cleaner code

? Improve testability

? Ensure a sustainable architecture

Which navigation approach do you prefer in your SwiftUI projects? ??

Let’s discuss in the comments! ????

?? What this post includes:

? A clear explanation of why Coordinator Pattern is better for large-scale apps

? A visual representation of modular navigation flow

? A comparison table showing the advantages of the Coordinator Pattern

?? If you found this helpful, share your thoughts and experiences in the comments! ??