10 — Interaction Specification (Communication Module)

• 1. Navigation
• 2. Feed interactions
• 3. Detail interactions
• 4. Compose interactions
• 5. Receipts sheet interactions
• 6. Threads (secondary)
• 7. Motion & feedback map
• 8. Offline & error policy
• 9. A11y essentials

Precise interactions: navigation, gestures, feedback, motion. Tokens/motion from 00-shared/08 (m-fast/m-base), a11y baseline from 00-shared/09, API conventions from 00-shared/07.

1. Navigation

Back semantics: sheets dismiss; pages pop; deep link to detail needs GET :id (planned).

2. Feed interactions

• Pull-to-refresh: RefreshIndicator, 500 ms min spinner; refetch list, preserve scroll position.
• Unread dot: 8 dp amber dot, semantics "Unread"; removed optimistically when the user reads the item (before server confirms — rollback on error).
• Draft rows (author): amber-free; "Draft" badge; tap → detail with "Publish" CTA.
• Long-press row: AppMenu (authors): "View receipts". (No delete — no API.)
• Tablet: row tap updates right pane; active row highlighted; Back restores list focus.

3. Detail interactions

• Mark as read: filled button; on tap → optimistic checkmark + POST /announcements/:id/read (announcement.repository.ts:20-33); success → snackbar (suppressed if silent preference (proposed)); 404 → snackbar + pop (announcement.service.ts:100).
• Auto-read on open: (proposed) toggle in settings; default off until product decision (06 §8 OQ-2).
• Attachments: tap → external browser (list is URL strings, create-announcement.dto.ts:45-49); no in-app viewer.
• Audience line: pure metadata display; no drill-down (no audience API).

4. Compose interactions

• Field focus flow: title → body → audience; TextInputAction.next chain; body multiline with toolbar.
• Audience change: selecting a type re-renders value control; picking all clears value; custom picker is search-as-you-type over users (user search API needed — (planned)).
• Recipient preview: (planned) — count chip below audience ("120 people will see this"); computed client-side only when custom (targetUserIds known); otherwise (planned) server estimate.
• Dirty-guard: leaving composer with edits → confirm dialog "Discard draft?".
• Publish flow: Publish = save + publish sequentially (08 §3); button becomes spinner; double-tap disabled; failure keeps draft + error snackbar + retry.
• Draft save: implicit on publish failure; explicit "Save draft" secondary button.

5. Receipts sheet interactions

• Segmented Read/Unread (AppSegmentedControl): instant refilter, no refetch.
• Pull-to-refresh + auto-refresh every 30 s while open (proposed).
• Rows: plain tiles; tap user → profile (forward-looking).
• ALL-audience degradation: counts hidden, list only (09 §3).

6. Threads (secondary)

• Send bar: TextField + send button; optimistic bubble; error → red tick + retry.
• Unread badge on thread tile; PATCH /threads/:id/read on open (IMPLEMENTATION_PLAN.md:112).
• Realtime via WS (planned) (IMPLEMENTATION_PLAN.md:119).

7. Motion & feedback map

8. Offline & error policy

9. A11y essentials

• Unread dot: semantics "Unread" (never color-only).
• Audience chips: Semantics(label: "Audience: Grade 10").
• Receipts counts announced on change (live region).
• Compose errors: inline + focus first invalid + live region (00-shared/09).