Implement WCAG Accessibility Audit for Driver Screens
epic-driver-and-confidentiality-management-ui-task-013 — Run a comprehensive WCAG 2.2 AA accessibility audit across all driver UI screens: DriverAssignmentList, DeclarationSendScreen, DeclarationAcknowledgementScreen, and DriverFeeRegistrationForm. Verify screen reader label completeness (VoiceOver/TalkBack), touch target sizes, color contrast ratios for all status badge colors, focus traversal order, and live region announcements for async state changes. Document and fix all identified violations.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 4 - 323 tasks
Can start after Tier 3 completes
Implementation Notes
Start with automated checks using Flutter's meetsGuideline matchers to triage the bulk of issues quickly. Then proceed to manual screen reader testing for nuanced issues (live regions, focus order, meaningful label context) that automated matchers cannot fully detect. For live region announcements, use Flutter's SemanticsService.announce() or wrap async state transition widgets in a Semantics node with liveRegion: true. For the scroll gate accessibility issue on DeclarationAcknowledgementScreen, consider adding a Semantics(explicitChildNodes: true) wrapper and ensure TalkBack users can navigate to the checkbox regardless of scroll position via the accessibility tree.
Color contrast fixes must be applied in src/visualization/styles.css or the design token system — never hardcode corrected colors inline in widget files. Refer to WCAG 2.2 criterion 1.4.3 (Contrast), 2.5.5 (Target Size), 4.1.3 (Status Messages) as the primary checklist.
Testing Requirements
Use Flutter's built-in meetsGuideline() accessibility matcher (tester.pumpAndSettle + expect(tester, meetsGuideline(androidTapTargetGuideline)) and iOSTapTargetGuideline) for all four screens. Use meetsGuideline(textContrastGuideline) for color contrast. Manually test with VoiceOver on iOS and TalkBack on Android against a physical device or simulator for each screen. Document each manual test step in the audit report.
Automated tests should be added to the widget test suite so regressions are caught in CI. All accessibility widget tests must pass before the task is closed.
The declaration acknowledgement screen has the most complex accessibility requirements of any screen in this feature: scrollable long-form legal text, a conditional checkbox that is only enabled after reading, and a timestamp capture. Incorrect focus management or missing semantics annotations could fail VoiceOver navigation or cause the screen reader to announce the checkbox as available before the driver has scrolled, undermining the legal validity of the acknowledgement.
Mitigation & Contingency
Mitigation: Build the acknowledgement screen against the WCAG 2.2 AA checklist from the start, not as a post-hoc audit. Use semantics-wrapper-widget and live-region-announcer from the platform's accessibility toolkit. Include a VoiceOver test session in the acceptance criteria with a tester using the screen reader.
Contingency: If WCAG compliance cannot be fully achieved within the sprint, ship the screen with a documented list of accessibility gaps and a follow-up sprint commitment. Do not block the declaration workflow launch if the core interaction works but a non-critical semantics annotation is missing.
Drivers receive a push notification with a deep link to the declaration acknowledgement screen for a specific assignment. If the deep link handler does not correctly route to the right screen and assignment context — particularly when the app is launched cold from the notification — the driver may see a blank screen or the wrong declaration.
Mitigation & Contingency
Mitigation: Implement and test all three notification scenarios: app foregrounded, app backgrounded, and cold start. Use the platform's existing deep-link-handler infrastructure. Add integration tests that simulate notification tap events and assert correct screen and data loading.
Contingency: If cold-start deep link routing proves unreliable, implement a notification-centre fallback where the driver can find the pending declaration from the notification centre screen, ensuring the workflow can always complete even if the direct deep link fails.
If the driver-feature-flag-guard has any rendering edge case — such as a brief flash of driver UI before the flag value is loaded, or a guard that fails open on a flag service error — driver-specific UI elements could be momentarily visible to coordinators in organizations that have not opted in, causing confusion and potentially a support escalation.
Mitigation & Contingency
Mitigation: Default the guard to rendering nothing (not a loading indicator) until the flag value is definitively resolved. Treat flag service errors as flag-disabled to fail closed. Write widget tests covering the loading, disabled, and enabled states including the error case.
Contingency: If fail-closed cannot be guaranteed within the sprint, add a server-side RLS check on the driver assignment endpoints so that even if the UI guard leaks, the data layer refuses to return driver data for organizations without the flag enabled.