Phase 20 · Lesson 04

Task Table and Domain Presentation

≈ 2 min core reading · 293 source/companion words
Learning contract

What you should be able to do after this

  • Explain Task Table and Domain Presentation without relying on framework buzzwords.
  • Connect the lesson to the phase outcome: Build a production application shell and reusable UI states instead of isolated demo components.
  • Reproduce the relevant behavior and verify it with evidence.
  • Diagnose at least one representative failure instead of guessing.
Figure 20.4 — TaskFlow boundary map
route/layout
server data boundary
page composition
client interaction islands
responsive/accessibility states
This lesson belongs to Phase 20. Keep the full request/data path visible even when today's code changes only one box.
Instructor workflow: predict first → implement the smallest slice → run it → inspect evidence → break one assumption → diagnose → explain it back. Do not copy the whole code block before understanding the first failing boundary.

Task Table & Domain Presentation Present operational data with semantic, responsive and scannable UI

Phase 20 - Production Application UI Volume 06 - Professional Frontend

Architecture milestone

Authorized task data

v

Semantic table

v

Status/priority/assignee

v

Responsive table region

Phase 20 turns the secure full-stack foundation into a coherent, accessible application interface without moving business authority into the browser.

A data table should be a table when the data is tabular Tasks are naturally compared across columns: status, priority, assignee, due date. A semantic HTML table provides relationships that div-based card grids must recreate manually for assistive technology.

Code
<table>
<caption>Tasks visible in your current workspace scope</caption>
<thead>
<tr>
<th scope="col">Task</th>
<th scope="col">Status</th>
<th scope="col">Priority</th>
<th scope="col">Assignee</th>
<th scope="col">Due</th>
</tr>
</thead>
<tbody>...</tbody>
</table>

Responsive strategy for real tables Do not collapse important business data into unreadable 320px cells. Keep a minimum table width and place it inside a labeled horizontal-scroll region. For mobile-first task workflows, a later alternate card/list view can be added intentionally rather than by CSS accident.

Figure 1 - Table responsiveness

Desktop: full table visible

v

Tablet: compressed but readable

v

Mobile: contained horizontal scroll

v

Future: optional purpose-built list view

Horizontal scroll is acceptable when the content is genuinely tabular and the region is discoverable and keyboard reachable.

Status and priority communicate with text + color A green pill labeled “Done” is better than a green dot with no accessible text. Color reinforces meaning but never carries it alone.

Do not turn every row into one giant click target

Keep the task title as a clear link and keep future row actions as real buttons. This preserves keyboard semantics and avoids nested interactive controls.

Executable lesson studio · ui

Now turn the explanation into engineering skill.

Task Table and Domain Presentation matters because it changes a real boundary in TaskFlow. The goal is to understand the inputs, owner, observable output, and failure modes before adding more abstraction.

By the end, you should be able to

  • Explain Task Table and Domain Presentation in terms of concrete inputs, ownership, outputs, and evidence.
  • Implement or reproduce the smallest TaskFlow slice that demonstrates this ui concept.
  • Diagnose one representative ui failure using observable evidence instead of trial-and-error.
Figure 20.4B — Mental model
route data
UI state
component tree
interaction
accessible feedback
Read left-to-right while implementing. When debugging, walk right-to-left until the first observed fact differs from your prediction.
Code-along sequence

One coherent change at a time

  1. 01

    Restate the goal of “Task Table and Domain Presentation” as one observable behavior. Write the success signal before touching code.

  2. 02

    Trace the boundary map: route data → UI state → component tree → interaction → accessible feedback. Mark the one boundary this lesson changes.

  3. 03

    Inspect the current repository state and record the exact files, route, table, or runtime involved. Avoid creating an abstraction before you can name the existing owner.

  4. 04

    Implement the smallest vertical slice. Add one coherent change, run the narrowest verification command, and read the output before continuing.

  5. 05

    Connect the slice to TaskFlow’s phase artifact: TaskFlow responsive shell with navigation, workspace context, task screens, loading/empty/error states, and accessible interactions.. Verify behavior from the outside as a user or API client would.

  6. 06

    Create one controlled failure that is safe to reproduce. Predict the symptom first, capture evidence, locate the earliest broken boundary, then fix only that cause.

  7. 07

    Close the reference and rebuild or explain the core change from memory. Record what you would monitor or test before trusting the same change in production.

tsxModel non-happy states intentionally
if (query.isPending) return <TaskSkeleton />;
if (query.isError) return <TaskError retry={query.refetch} />;
if (!query.data.length) return <EmptyTasks />;
return <TaskTable tasks={query.data} />;

Do not copy this as a finished answer. Predict what each boundary does, type the smallest useful slice, run it, then compare the result with your prediction.

Verification

Prove the happy path

  1. Run the narrowest relevant command or request and require a clean exit/status.
  2. Inspect the boundary-specific evidence: terminal output, Network panel, database row/query plan, test report, container health, or deployment logs.
  3. Repeat the behavior once after the change so a one-off cached or stale result cannot masquerade as success.
Break it on purpose

Build debugging memory

  1. Mobile layout treated as desktop squeezed smaller
  2. Change one assumption in the ui example—identity, input, configuration, ordering, connectivity, or state—and predict the exact symptom before running it.
SymptomInvestigation path
Expected result does not appear

Return to the nearest observable boundary: input, network, process log, database, or rendered UI. Compare actual evidence with the predicted path.

A shortcut appears to fix it

Change one variable at a time and reproduce the original failure after the fix; otherwise you have correlation, not diagnosis.

Closed-reference challenge

Can you transfer the idea?

Without copying the final source, create a second small scenario that applies “Task Table and Domain Presentation” to a different TaskFlow resource or input. Write the acceptance criteria first, implement it, and provide the evidence that each criterion is satisfied.

Explain-back

Answer these without reopening the solution

  1. What problem does Task Table and Domain Presentation solve in TaskFlow, and what would be observably wrong without it?
  2. Which part of the ui boundary owns the decision, and which neighboring layer must not own it?
  3. What evidence proves the happy path instead of merely suggesting it worked?
  4. Name one realistic failure or abuse case and the first place you would inspect.
  5. If requirements doubled tomorrow, which part of this design should stay stable and which part is allowed to change?
Lesson studio

Turn the reading into skill

01

Do it

Compose Server and Client Components so interactive islands remain small.

Use the smallest change that demonstrates this lesson. Stop after it works and capture evidence.
02

Break it safely

Mobile layout treated as desktop squeezed smaller

Predict the symptom before causing the failure. Then locate the earliest boundary where reality diverges from expectation.
03

Explain it back

Why does this responsibility live here, what input does it trust, what output proves success, and what would go wrong if another layer owned it?

If your explanation is vague, repeat the boundary trace before moving on.
Exit ticket

Before marking complete

Close the reference. Reproduce the core idea from memory or explain the exact request/data flow aloud. Then check your diff or notes for accidental shortcuts that bypass validation, authorization, error handling, or verification earned in earlier phases.