Behavior-Preserving View Refactoring
Load this reference when restructuring an existing SwiftUI view without an explicit request to change its interface or behavior.
Contents
Pin the Contract
A structure-only refactor preserves:
- layout, presentation, and navigation behavior;
- accessibility labels, values, actions, focus order, and identifiers;
- state ownership, bindings, and stable view identity;
- side-effect timing and cancellation behavior;
- domain behavior, error handling, and persistence semantics.
Record intentional changes separately. Do not let cleanup silently become a visual redesign, navigation rewrite, or business-rule change.
Use the extraction signals in the main skill. Dedicated View types are the default
for sections with substantial layout or branching, their own state or lifecycle,
narrower dependencies, independent preview value, or enough complexity to obscure
the parent's data flow. Keep only genuinely small stateless fragments as computed
some View properties. Extensions and // MARK: headings organize a file; they do
not create view boundaries. Do not replace one oversized body with a screen-sized
extension made of computed some View fragments.
Keep Body Declarative
Move non-trivial button actions and lifecycle closures to small named methods so
body reads as UI:
Button("Save", action: save)
.disabled(isSaving)
.task(id: searchText) {
await reload(for: searchText)
}
private func save() {
Task { await editorService.validateAndSave(draft) }
}
private func reload(for query: String) async {
results = await searchClient.results(for: query)
}The view methods remain thin orchestration points. They may update view-owned loading, selection, error, or presentation state around a service/model call.
Preserve the Business Boundary
Validation, persistence, networking, retry/caching rules, and reusable loading policy belong in services or models. Do not merely move a large inline closure into an equally large private view method and call the refactor complete.
Keep reusable domain errors and their recovery policy with the service or model that defines the operation. The view may translate those errors into presentation state, but it should not become the owner of domain failure semantics.
Pass extracted subviews only the values, bindings, and actions they need. Preserve the existing environment-versus-initializer ownership decision unless changing that boundary is part of the request. If a child needs a cohesive feature-scoped observable model, pass that model explicitly instead of replacing its interface with many unrelated closures.
Verify the Refactor
After each meaningful extraction:
- Build the affected target and fix compiler errors before continuing.
- Run existing unit, snapshot, and UI tests that cover the screen.
- Render independently useful previews with deterministic fixtures and every required dependency installed.
- Exercise the original interaction flow, including loading, error, cancellation, save/dismiss timing, navigation, focus, and accessibility behavior.
- Review the diff for accidental constants, modifier-order, identity, or task-lifetime changes.
Preserve existing preview-rendering and snapshot-test CI gates. Compilation alone does not prove that extracted views still compose or render correctly.
A cleaner file that changes behavior, weakens a required dependency, or no longer builds is not a successful refactor.