How to structure a large SwiftUI screen

When an interviewer hands you a big SwiftUI feature, the test is decomposition: can you keep it readable, testable, and performant as it grows.

Breaking the screen down

Split the screen into small subviews with single responsibilities, each taking only the state it needs via bindings or an observed model. Keep body cheap so each subview invalidates independently, and give repeated elements stable identity. A flat pile of modifiers in one giant body is the anti-pattern to avoid.

State and dependencies

Put presentation logic and state in a view model or an @Observable model that the view owns, so the view stays declarative and the logic is unit testable without the UI. Inject dependencies rather than constructing them inside the view, and lift shared state to the lowest common owner. Describe how this keeps the feature modular as requirements grow.

Go deeper than a summary

Share Your Screen works topics like this through in full: 75 solved Swift problems with tests, 9 real case studies, and 7 annotated mock interviews, so you rehearse the live round instead of just reading about it.

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Frequently asked

How do you keep a large SwiftUI view manageable?

Decompose it into small single-purpose subviews, give each only the state it needs, and move logic into an observable model the view owns.

Where should the logic live?

In a view model or @Observable model, not in the view body, so the logic is testable and the view stays declarative and cheap to re-render.