Add Cancel and Override Actions to Warning Dialog
epic-proxy-activity-registration-ui-task-006 — Implement Cancel (dismiss dialog, return to form) and Override (confirm submission despite conflict) action buttons inside DuplicateWarningDialog. Dispatch the appropriate BLoC events on each tap. Add semantic labels and focus management so screen readers announce the choice correctly.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 14 - 3 tasks
Can start after Tier 13 completes
Implementation Notes
Use BlocConsumer or BlocBuilder to read submitting state for button disable logic. Create a FocusNode in the widget's State (or use autofocus: true on the Cancel button) to ensure correct initial focus. The Override button should use a destructive color from AppColors (e.g., AppColors.warning or AppColors.error) — coordinate with design system. Use the existing AppButton widget passing a loading parameter if supported, otherwise wrap in AbsorbPointer + Opacity when in SubmittingOverride state.
Ensure the action row uses MainAxisAlignment.end or spaceBetween with adequate spacing (AppSpacing.sm between buttons). After BLoC emits SubmissionSuccess or SubmissionFailure following override, the parent BlocListener (not this dialog) should handle navigation or error toast — keep the dialog's responsibility limited to event dispatch and self-dismissal.
Testing Requirements
Unit/BLoC tests: verify CancelConflictResolution and ConfirmOverrideSubmission events are emitted correctly. Widget tests: (1) tap Cancel and assert Navigator.pop is called and correct BLoC event fired; (2) tap Override and assert BLoC event fired; (3) set BLoC state to SubmittingOverride and assert both buttons are disabled; (4) verify FocusNode is attached to Cancel button on dialog open. Accessibility: use flutter_test's tester.getSemantics() to verify semantic labels on both buttons.
The bulk registration screen combines pre-filled defaults, a dynamic multi-select participant list, per-participant conflict badges, and a batch submission confirmation — making it one of the most complex screens in the application. Scope creep or underestimated interaction complexity could cause the epic to exceed its estimate significantly.
Mitigation & Contingency
Mitigation: Implement the bulk screen in two vertical slices: (1) participant selection and form submission without conflict handling, (2) conflict badge rendering and override flow. Validate slice 1 with coordinators before building slice 2.
Contingency: If the full conflict review UI cannot be completed within the epic, ship the bulk screen with a simplified 'skip all duplicates' fallback mode and defer per-participant override toggles to a follow-up sprint.
The proxy-registration-bloc must manage state across two distinct flows (single proxy and bulk) with branching conflict paths, intermediate buffering of bulk participant selections, and reliable state reset. Incorrect state transitions could leave the UI in a loading or stale-conflict state after submission.
Mitigation & Contingency
Mitigation: Model the BLoC state as a sealed class hierarchy with exhaustive pattern matching in the UI. Write state-machine unit tests that exercise every valid transition and assert that invalid transitions are no-ops. Use flutter_bloc's BlocObserver in debug builds to log all transitions.
Contingency: If BLoC state bugs surface in QA, introduce an explicit ResetToIdle event triggered on screen disposal to guarantee clean state, and add a 'Start over' affordance visible to the coordinator at any conflict step.
The typeahead peer mentor selector with multi-select mode may be difficult to operate with VoiceOver/TalkBack, particularly the dynamic search results list and the selected-chip removal controls, risking WCAG 2.2 AA non-compliance for screen reader users.
Mitigation & Contingency
Mitigation: Wrap all search result items and selected chips with explicit Semantics widgets providing role, label, and selected-state announcements. Test the selector with VoiceOver on iOS and TalkBack on Android during development, not only at QA time.
Contingency: If the multi-select typeahead cannot be made fully accessible within the sprint, provide an alternative flat scrollable list with checkboxes as a fallback mode, toggled by an accessibility-settings flag.
The peer mentor selector must apply RLS chapter-scope filtering to show only mentors the coordinator is responsible for. If the Supabase query for the selector does not correctly join against the coordinator's chapter assignments, coordinators may see mentors from other chapters, violating data isolation.
Mitigation & Contingency
Mitigation: Implement the selector's data query using the same RLS-aware Supabase client used by the contact list feature, which already handles chapter-scope filtering. Write an integration test with a multi-chapter coordinator fixture asserting cross-chapter mentors are not returned.
Contingency: If a data isolation breach is discovered, immediately add a client-side chapter_id filter as a defence-in-depth measure and audit selector query logs for any unauthorised cross-chapter results.