Scaffold PeerMentorDetailScreenWidget layout structure
epic-peer-mentor-detail-screen-bloc-and-assembly-task-007 — Create the top-level PeerMentorDetailScreenWidget Flutter screen with a scrollable layout using CustomScrollView with SliverList. Define placeholder sections for: profile header, certification alert banner, assigned contacts list, and activity summary panel. Apply design token theme for spacing, typography, and colors consistent with the app's design system.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 5 - 253 tasks
Can start after Tier 4 completes
Implementation Notes
Structure the file as a single public `PeerMentorDetailScreenWidget` (StatelessWidget) containing a `Scaffold` wrapping the `CustomScrollView`. Define private `_ProfileHeaderSection`, `_CertificationAlertBannerSection`, `_AssignedContactsListSection`, and `_ActivitySummaryPanelSection` widgets in the same file as unexported classes — they will be extracted to separate files in subsequent tasks when implemented. Use `SliverPadding` around each section to apply consistent horizontal/vertical padding from design tokens. The `SliverAppBar` should use `pinned: true` so the app bar stays visible on scroll, aiding navigation for users relying on VoiceOver (WCAG 2.2 success criterion 2.4.3 Focus Order).
For pull-to-refresh, use `CupertinoSliverRefreshControl` inside the CustomScrollView for consistent iOS behavior, or a platform-adaptive approach. Ensure all section wrappers have `Semantics(header: true)` so screen readers announce section boundaries — critical for Blindeforbundet users on VoiceOver.
Testing Requirements
Widget tests (flutter_test): (1) Golden test — render screen in loading state (PeerMentorDetailLoading) and assert layout matches approved golden image for 375 and 430 width viewports. (2) Overflow test — pump widget in a 375×667 constraint, assert no RenderFlex overflow errors. (3) Section presence — assert each of the 4 section title strings is findable via `find.text()`. (4) Scroll test — pumpAndSettle, then drag the CustomScrollView; assert scroll position changes without exception.
(5) Accessibility test — use `tester.ensureVisible` and `SemanticsController` to assert all interactive elements have semantic labels. (6) Theme test — render in dark mode ThemeData and assert no hardcoded-color violations via golden diff. Run accessibility audit with `flutter_test`'s `SemanticsController.checkSemantics()` to verify WCAG-level contrast.
The parallel Future.wait aggregation pattern may produce race conditions or incorrect merged state when some repositories resolve significantly faster than others, particularly if the BLoC receives a RefreshDetail event while a prior fetch is still in flight.
Mitigation & Contingency
Mitigation: Implement cancellation token pattern in the aggregation service to abort in-flight fetches on new events. Add BLoC test scenarios for rapid successive refresh events to validate state consistency.
Contingency: If race conditions persist, switch to a sequential-with-timeout fetch strategy for the first release and profile the performance impact before deciding whether parallel fetch optimization is worth the complexity.
Integrating PeerMentorDetailScreenWidget into the existing StatefulShellRoute navigation structure may conflict with the Contacts tab's existing route hierarchy, requiring changes to navigation-route-config that could affect other teams' features.
Mitigation & Contingency
Mitigation: Coordinate with the Contact List and Contact Detail feature teams before adding the new route. Review the existing StatefulShellRoute configuration and confirm the peer mentor detail route can be nested under the Contacts branch without path conflicts.
Contingency: If route conflicts arise, temporarily implement the peer mentor detail as a modal overlay (push route) rather than a shell route child, preserving functionality while the navigation architecture conflict is resolved.
The course enrollment screen that the certification alert banner links to may not yet exist or may be implemented in a separate feature epic, leaving a broken navigation tap for HLF users in the initial release.
Mitigation & Contingency
Mitigation: Check the certification management feature implementation status before finalizing Epic 4 scope. If the enrollment screen is not available, design the tap action to open the HLF course enrollment URL in an external browser as an interim solution.
Contingency: Implement the CTA as a configurable action: if the enrollment route exists in the router, push it; otherwise, launch the configured org-specific enrollment URL via url_launcher, ensuring HLF users can always take action on expired certifications.