Forms & inputExplore · Adapt · Compose
Textarea
Textarea captures longer multi-line user input. Make the expected input clear before someone interacts, and keep the current value, help text and validation feedback connected. Explore the live examples, inspect their source and choose the composition that fits your interface before connecting it to your application's data.
The examples use @/components/kamod-ui/textarea in a Preact project. Follow the live result and its source together: compare supported options in the API reference, refine presentation with the component styles guide, and use shared theme tokens for consistent colors and surfaces. Preserve keyboard behavior and meaningful labels as you replace the sample content.
In this guide 7 sections
Installation
Import Textarea from @/components/kamod-ui/textarea.
pnpm add @kamod-ch/uiThe @/components/kamod-ui/… imports in these examples refer to local source files. Configure that alias when copying source, or use the corresponding exports from @kamod-ch/ui when installing the package. Connect the global theme CSS and Tailwind source detection before your first render.
Usage
Use Textarea with Field for labels, descriptions, errors, and more modern form layouts.
import { Textarea } from "@/components/kamod-ui/textarea";Choose a complete composition from the examples below; required child components and props vary by pattern.
Component examples & variants
Explore Textarea in different contexts, from the starting pattern to the compositions below. Begin with Basic Textarea, then compare the examples that match your content, state and layout. These are working patterns to adapt, not a list of interchangeable variant values: check the API reference before using a prop or combining behaviors. Look at the surrounding labels, supporting text and spacing as well as the component itself.
Read the result and its implementation together. Use each showcase’s Code view to inspect imports and composition, or its Prompt view to prepare a setup or adaptation brief. Try the narrow preview and local theme controls before connecting real data, and use Reset to return an example to its initial state. Keep layout changes in class utilities where appropriate; follow the component styles guide for hierarchy and the theming guide for shared surfaces and colors. The accessibility notes explain what to preserve when making those changes.
Basic Textarea
A clean default surface for short notes and feedback.
import { Textarea } from "@/components/kamod-ui/textarea";
export const Example = () => <Textarea placeholder="Write your feedback..." class="max-w-lg" />;Field + Description
Wrap Textarea with Field for semantic labels and helper text.
Disabled + Invalid
Support disabled and invalid states with clear visual feedback.
Textarea Sizes
Render size variants for compact and roomy layouts.
Character Counter
Track input length in real time for message limits and form guidance.
Auto-resize
Auto-grow textarea height on input for longer, distraction-free writing.
Production Field Pattern
Combine label, hint, validation error and live character count in one practical form pattern.
Textarea + Action
Pair the input with a trailing action for modern message flows.
Props and data
Configure Textarea using the contracts below. Read the documented options alongside the source definitions to understand which values your application supplies and which details the component owns. Start with a prop or helper, then follow its type link to inspect the declaration without leaving the page.
Props, slots and variants for this component.
TypeScript source at build time. Props inherited through HTMLAttributes, Omit or variant helpers remain references in those declarations; their fields are not flattened here. Match the reference to your installed version, and check a package’s exports before writing an import type. A type exported by a source file is not necessarily re-exported by @kamod-ch/ui.TypeScriptComponent props
? means a field can be omitted; it does not promise a fallback value. Existing documented defaults remain alongside the descriptions. For callbacks, check the argument and return types before connecting your own state or services.Textarea
Textarea component props and accepted values.
| Prop / type | Description |
|---|---|
size | Documented size option for Textarea. Check its type alongside the usage examples before supplying a value. Documented default |
aria-invalid | Documented aria-invalid option for Textarea. Check its type alongside the usage examples before supplying a value. Documented default |
placeholder | Documented placeholder option for Textarea. Check its type alongside the usage examples before supplying a value. Documented default |
disabled | Documented disabled option for Textarea. Check its type alongside the usage examples before supplying a value. Documented default |
Data type reference
Expand a card to inspect and copy the exact declaration. The code header identifies its repository file; follow imported or inherited types in the implementation source when you need the complete dependency chain. Required-field summaries cover fields declared directly in that type. Source-only helpers and inferred schema outputs describe the local implementation, not additional props you can pass to every component.
TextareaPropsAccessibility
Build the complete interaction, including the parts outside Textarea. The notes below distinguish the current implementation from the labels, content and behavior your application supplies. Start with the live preview, check the props and data reference, and test the finished composition with real content rather than assuming that an unchanged visual example covers every use case.
Built-in behavior and defaults
Textarea keeps native multiline editing and forwards textarea attributes. Styling for aria-invalid communicates the visual error state; it does not create an error description or a character-limit announcement.
Labels and relationships
Use a visible label and describe the expected content, length and privacy boundaries before entry. Give help and error text stable IDs. If showing a remaining-character count, connect it as a description and avoid announcing every keystroke through an assertive live region.
Keyboard and focus
Allow Enter to create a new line unless a clearly explained application interaction requires otherwise. Preserve selection, paste and undo. If a chat composer uses a submission shortcut, describe the shortcut and retain a normal Send button.
States and integration details
Do not fix the height so tightly that long text or enlarged fonts become unreadable. Distinguish a maximum enforced by maxLength from a recommended length, and preserve the entered draft when a request fails.
Verify the complete interaction
Check behavior as well as markup. Work through these scenarios in the application where the component will be used. Automated checks can help find structural problems; also review the reading experience with a screen reader, keyboard focus and the actual feedback from your application.
- Read the label, instructions and error with the field focused; a placeholder alone must not carry the task.
- Paste several paragraphs and use the keyboard to reach both the start and end of the text.
- Increase text size and resize the viewport; keep the caret, validation and submission action reachable.
Recheck the result after changing theme tokens, translations or class overrides. Include text enlargement, narrow layouts and reduced-motion settings where animation is present. Inspect the component source when a behavior differs from your expectation; a role or state attribute does not implement keyboard interaction by itself.
For background, read the WAI-ARIA authoring guidance and keyboard interface guidance. These explain the patterns; verify browser and assistive-technology behavior for the implementation and audience you actually support.
Build it into your interface
Use the Textarea examples as a starting point, then review the behavior in the context of your own screen. Layout, state and content should work together.
Connect the behavior
Choose where the value lives before wiring up validation. Use the documented change callback, preserve the field name when submitting a native form, and associate help or error text with the control. A placeholder supplements a label; it does not replace one.
Copy the composition, then connect its intent. Replace sample records and callbacks with your own data flow. For options such as value, defaultValue, open or onChange, use only those documented in this component's API; different components expose different contracts.
Give each piece of state one owner. Keep a temporary selection inside the interface when nothing else needs it; lift shared values into a parent when other controls depend on them. Read the prop reference before combining controlled values with defaults. A default normally initializes a control; it is not a substitute for updating its current value.
Connect requests in an event handler or your application’s data layer, never as a side effect of rendering. Keep pending, completed and failed outcomes distinct, preserve useful input after an error, and offer a clear recovery action. If the integration subscribes to an external source, remove that subscription when its owner unmounts; cancel or ignore obsolete requests so an earlier response cannot replace newer results.
Start with the live preview, then exercise the same interaction with your actual data. The type definitions describe accepted values; they do not implement persistence, navigation or server-side validation for you. Keep those responsibilities in the application that composes the UI.
Refine the presentation
Let a parent own the surrounding spacing. Keep related elements together with gap and use semantic surface/foreground pairs so the composition follows the active theme. The wrapper below changes the surrounding layout without assuming extra props on Textarea.
import type { ComponentChildren } from "preact";
export function ExampleSurface({ children }: { children: ComponentChildren }) {
return (
<div class="grid min-w-0 gap-4 rounded-lg border border-border bg-card p-4 text-card-foreground sm:p-6">
{children}
</div>
);
}Put the chosen example inside ExampleSurface, then refine supported variants and sizes using the API above. For application-wide changes, adjust theme tokens instead of repeating fixed colors. See Component styles for hierarchy, density and focus treatments.
Review the complete interaction
- Try an empty value, a valid value and a rejected value; keep the correction visible beside the field.
- Navigate using only the keyboard and verify the label identifies the focused control.
- Check disabled and read-only behavior separately where supported; they communicate different intentions.
The preview's narrow control changes its container width. Also resize the browser when checking viewport-based Tailwind utilities such as sm: and md:, and test overlays in the full page where their portals render.
Compose a complete interface
Textarea is one part of the interaction. Choose companion components for the information or actions that still need a place on the screen. The references below are suggestions to compose deliberately, not extra dependencies you must add to every example.
Keep one source of truth for the operation and let each component communicate a different part of it. For example, waiting, no results and failure need different explanations. Avoid showing contradictory states together, and keep recovery actions close to the message that explains them.
Start with the smallest composition that explains the task. Browse the component library for individual controls or the block collections for complete layouts. Reuse shared theme tokens so these pieces feel consistent in light and dark mode.
Sources & design references
Follow Textarea from its implementation to the ideas behind your own composition. Start with the local API, explore a visual direction, then bring the result back to your app’s shared styles.
Bring it back to your app
A reference becomes useful when it fits your real content. Work through these decisions in order:
- Keep the behavior grounded. Start with the interactive examples, then connect your data and callbacks using the integration guidance. Preserve labels, keyboard access and disabled states as you change the presentation.
- Make the styling repeatable. Use the styles guide for local
classadjustments and theming documentation for shared color decisions. Keep semantic surface and foreground pairs together in both light and dark mode. - Check the complete screen. See how components combine in the block collections, then try long labels, loading states and narrow layouts in your own composition. The Theme Toggle guide helps you expose a scheme switch in the finished interface.