Add accessibility semantics to registration screen
epic-coordinator-proxy-registration-core-task-012 — Apply WCAG 2.2 AA semantics throughout ProxyRegistrationScreen: add Semantics wrappers with meaningful labels to all form fields, announce validation errors via LiveRegion, ensure the mentor selector has a descriptive hint for screen readers, set logical focus order matching visual layout, and verify minimum 44×44dp touch targets for all interactive elements.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 6 - 158 tasks
Can start after Tier 5 completes
Implementation Notes
Prefer wrapping existing widgets with Semantics() over restructuring the widget tree — minimise scope of changes. For LiveRegion announcements on validation errors, use SemanticsService.announce(message, TextDirection.ltr) inside the BlocListener when a validation error state is emitted. To enforce 44dp touch targets on custom widgets, wrap with ConstrainedBox(constraints: BoxConstraints(minWidth: 44, minHeight: 44)). Use FocusTraversalGroup with OrderedTraversalPolicy and assign FocusTraversalOrder.order to each field widget.
Test with TalkBack on Android if the target audience includes Android users (NHF/HLF user base spans both platforms). Given this project's strong WCAG 2.2 AA requirement across all three workshop organisations (NHF, Blindeforbundet, HLF), treat this task as a quality gate — the screen should not ship without passing the VoiceOver walkthrough.
Testing Requirements
Write flutter_test widget tests using tester.getSemantics() to assert that each form field node has the expected label and hint. Use the flutter accessibility scanner (AccessibilityGuideline) to programmatically check contrast ratios and touch target sizes. Write a golden-free semantic tree snapshot test that serialises the SemanticsNode tree for ProxyRegistrationScreen in its default state and asserts expected node labels — this catches regressions when widget tree changes. Manually verify with VoiceOver on a real iOS device or simulator before marking complete.
The 2-hour window duplicate detection logic requires querying existing proxy records with compound key matching (mentor + date + activity type within time range). If the query is too broad it produces false positives that frustrate coordinators; if too narrow it misses genuine duplicates that corrupt Bufdir data.
Mitigation & Contingency
Mitigation: Define the duplicate detection window as a configurable parameter from the start. Prototype the Supabase query with representative data covering edge cases (midnight boundaries, different activity types same day, same activity type different mentors) before finalising the implementation.
Contingency: If the detection produces excessive false positives in UAT, allow coordinators to explicitly acknowledge and bypass the duplicate warning with a reason field, preserving safety while reducing friction.
If the proxy registration form does not clearly distinguish between the acting coordinator and the attributed mentor, coordinators may submit records attributing activities to themselves, causing inaccurate Bufdir reporting and potential funding issues.
Mitigation & Contingency
Mitigation: Conduct UAT with at least one real coordinator via TestFlight before release. Use distinct visual treatment (different card colours, explicit 'Registering on behalf of:' label) and require the confirmation screen to show both identities prominently.
Contingency: Add a mandatory confirmation checkbox on the confirmation screen that explicitly names the attributed mentor, preventing accidental self-attribution from slipping through.
Coordinators with multi-chapter access must select an active chapter context before the mentor list is filtered correctly. If chapter scope resolution fails or is bypassed, cross-org proxy registrations could occur, violating data isolation between chapters.
Mitigation & Contingency
Mitigation: Reuse the existing active-chapter-state and hierarchy-service components established by the org hierarchy feature. Add a guard that blocks entry to the proxy flow if no chapter context is active, prompting chapter selection first.
Contingency: If the chapter resolution service is unavailable, default to the most restrictive scope (no mentors visible) and surface a clear error message rather than showing an unfiltered mentor list.