Controller & Custom Components Know when native registration ends and an adapter is justified
Phase 21 - Forms with React Hook Form + Zod Volume 06 - Professional Frontend
Prefer register for native inputs React Hook Form works naturally with native input, textarea and select elements. Start with register. Use Controller/useController only when a component is controlled by design or does not expose a standard input ref/value contract.
register Controller
input date picker
textarea rich select
select custom combobox
checkbox third-party UI control
Controller pattern <Controller name="assigneeId" control={control} render={({ field, fieldState }) => ( <AssigneeCombobox value={field.value} onChange={field.onChange} onBlur={field.onBlur} error={fieldState.error?.message} /> )} />
Do not wrap everything in Controller Controller adds an adapter layer. Native controls already integrate well through register and are usually simpler and more accessible. Reach for Controller when the component API requires it, not because a form library example happened to use it.
Reusable form-field components A reusable Field component can own label/help/error layout, but avoid hiding register/control behavior behind a component so generic that no one can understand where values and errors come from.
Controller Custom Components and Field Composition 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.
Restate the goal of “Controller Custom Components and Field Composition” as one observable behavior. Write the success signal before touching code.
Trace the boundary map: route data → UI state → component tree → interaction → accessible feedback. Mark the one boundary this lesson changes.
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.
Implement the smallest vertical slice. Add one coherent change, run the narrowest verification command, and read the output before continuing.
Connect the slice to TaskFlow’s phase artifact: Create/edit task forms with shared field rules, accessible errors, async submission, server-error mapping, and reset behavior.. Verify behavior from the outside as a user or API client would.
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.
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.
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.
Return to the nearest observable boundary: input, network, process log, database, or rendered UI. Compare actual evidence with the predicted path.
Change one variable at a time and reproduce the original failure after the fix; otherwise you have correlation, not diagnosis.
Without copying the final source, create a second small scenario that applies “Controller Custom Components and Field Composition” to a different TaskFlow resource or input. Write the acceptance criteria first, implement it, and provide the evidence that each criterion is satisfied.
Connect Zod resolver and reuse only rules that genuinely belong in both client and API validation.
Use the smallest change that demonstrates this lesson. Stop after it works and capture evidence.Duplicating server data into form state without reset strategy
Predict the symptom before causing the failure. Then locate the earliest boundary where reality diverges from expectation.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.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.