packages/react-aria-components/docs/ColorArea.mdx
{/* Copyright 2024 Adobe. All rights reserved. This file is licensed to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */}
import {Layout} from '@react-spectrum/docs'; export default Layout;
import docs from 'docs:react-aria-components'; import statelyDocs from 'docs:@react-stately/color'; import {PropTable, HeaderInfo, TypeLink, PageDescription, StateTable, ContextTable} from '@react-spectrum/docs'; import styles from '@react-spectrum/docs/src/docs.css'; import packageData from 'react-aria-components/package.json'; import Anatomy from '/packages/react-aria/docs/color/ColorAreaAnatomy.svg'; import ChevronRight from '@spectrum-icons/workflow/ChevronRight'; import {Divider} from '@react-spectrum/divider'; import {ExampleList} from '@react-spectrum/docs/src/ExampleList'; import {ExampleCard} from '@react-spectrum/docs/src/ExampleCard'; import Label from '@react-spectrum/docs/pages/assets/component-illustrations/Label.svg'; import {Keyboard} from '@react-spectrum/text'; import {StarterKits} from '@react-spectrum/docs/src/StarterKits';
<PageDescription>{docs.exports.ColorArea.description}</PageDescription>
<HeaderInfo packageData={packageData} componentNames={['ColorArea']} sourceData={[ {type: 'W3C', url: 'https://www.w3.org/WAI/ARIA/apg/patterns/slider/'} ]} />
import {ColorArea, ColorThumb} from 'react-aria-components';
<ColorArea>
<ColorThumb />
</ColorArea>
@import "./ColorSlider.mdx";
.react-aria-ColorArea {
width: 192px;
height: 192px;
border-radius: 4px;
flex-shrink: 0;
}
.react-aria-ColorThumb {
border: 2px solid white;
box-shadow: 0 0 0 1px black, inset 0 0 0 1px black;
width: 20px;
height: 20px;
border-radius: 50%;
box-sizing: border-box;
&[data-focus-visible] {
width: 24px;
height: 24px;
}
}
The <input type="color"> HTML element
can be used to build a color picker, however it is very inconsistent across browsers and operating systems and consists
of a complete color picker rather than a color area. ColorArea helps achieve accessible and
touch-friendly color areas that can be styled as needed.
<input> elements for mobile screen reader support and HTML form integration.<Anatomy role="img" aria-label="Color area anatomy diagram: Shows a color area component with labels pointing to its parts, including the area, and thumb elements." />
A color area consists of a rectangular background area that provides, using a two-dimensional gradient,
a visual representation of the range of color values from which a user can select, and a thumb that the user can drag
to change the selected color value. Two visually hidden <input> elements are used to represent the color channel
values to assistive technologies.
import {ColorArea, ColorThumb} from 'react-aria-components';
<ColorArea>
<ColorThumb />
</ColorArea>
{/*
*/}
To help kick-start your project, we offer starter kits that include example implementations of all React Aria components with various styling solutions. All components are fully styled, including support for dark mode, high contrast mode, and all UI states. Each starter comes with a pre-configured Storybook that you can experiment with, or use as a starting point for your own component library.
<StarterKits component="colorarea" />If you will use a ColorArea in multiple places in your app, you can wrap all of the pieces into a reusable component. This way, the DOM structure, styling code, and other logic are defined in a single place and reused everywhere to ensure consistency.
import type {ColorAreaProps} from 'react-aria-components';
export function MyColorArea(props: ColorAreaProps) {
return (
<ColorArea {...props}>
<ColorThumb />
</ColorArea>
);
}
<MyColorArea defaultValue="hsl(30, 100%, 50%)" />
A ColorArea requires either an uncontrolled default value or a controlled value, provided using the defaultValue or value props respectively.
The value provided to either of these props should be a color string or <TypeLink links={docs.links} type={docs.exports.Color} /> object.
xChannel and yChannel props may also be provided to specify which color channels the color area should display, and the direction of each channel in the color gradient.
This must be one of the channels included in the color value, for example, for RGB colors, the "red", "green", and "blue" channels are available.
For a full list of supported channels, see the Props table below.
By default, color area is uncontrolled, with a default value of white using the RGB color space (rgb(255, 255, 255)).
You can change the default value using the defaultValue prop, and the color area will use the color space of the provided value.
<MyColorArea defaultValue="hsb(219, 58%, 93%)" />
If no xChannel or yChannel is provided, for the RGB color space, the red color channel maps to the horizontal axis or xChannel,
and the green color channel maps to the vertical axis or yChannel. Similarly, for the HSL and HSB color spaces, the hue color
channel maps to the horizontal axis or xChannel, and the saturation color channel maps to the vertical axis or yChannel.
In the example below, the <TypeLink links={docs.links} type={docs.exports.parseColor} /> function is used to parse the initial color from an HSL string. This is passed to the value prop to make the ColorArea controlled, and updated in the onChange event.
import {parseColor} from 'react-aria-components';
function Example() {
let [value, setValue] = React.useState(parseColor('hsl(0, 100%, 50%)'));
return (
<>
<MyColorArea
value={value}
onChange={setValue}
xChannel="saturation"
yChannel="lightness" />
<p>Value: {value.toString('hex')}</p>
</>
);
}
ColorArea supports the xName and yName props for integration with HTML forms. The values will be submitted as numbers between the minimum and maximum value for the corresponding channel in the X and Y direction.
<MyColorArea xName="red" yName="green" />
ColorArea supports two events: onChange and onChangeEnd. onChange is triggered whenever the ColorArea's handle is dragged, and onChangeEnd
is triggered when the user stops dragging the handle. Both events receive a <TypeLink links={docs.links} type={docs.exports.Color} /> object
as a parameter.
The example below uses onChange and onChangeEnd to update two separate elements with the ColorArea's value.
function Example() {
let [currentValue, setCurrentValue] = React.useState(parseColor('hsl(50, 100%, 50%)'));
let [finalValue, setFinalValue] = React.useState(currentValue);
return (
<div>
<MyColorArea
value={currentValue}
onChange={setCurrentValue}
onChangeEnd={setFinalValue} />
<p>Current value: {currentValue.toString('hsl')}</p>
<p>Final value: {finalValue.toString('hsl')}</p>
</div>
);
}
To build a fully functional color picker, combine a ColorArea, which adjusts two channels of a color value, with a separate control, like a ColorSlider or ColorWheel, to adjust the value of the third channel.
import {ColorSlider, Label, SliderOutput, SliderTrack} from 'react-aria-components';
function Example() {
let [color, setColor] = React.useState(parseColor('hsl(50, 100%, 50%)'));
return (
<div>
<MyColorArea
value={color}
onChange={setColor}
xChannel="saturation"
yChannel="lightness" />
<ColorSlider channel="hue" value={color} onChange={setColor} style={{width: 192, marginTop: 8}}>
<Label />
<SliderOutput />
<SliderTrack>
<ColorThumb />
</SliderTrack>
</ColorSlider>
<p>Current value: {color.toString('hsl')}</p>
</div>
);
}
A color area can be disabled using the isDisabled prop. This prevents the thumb from being focused or dragged.
It's up to you to style your color area to appear disabled accordingly.
<MyColorArea defaultValue="#ff0" isDisabled />
.react-aria-ColorArea {
&[data-disabled] {
background: gray !important;
.react-aria-ColorThumb {
background: gray !important;
}
}
}
By default, ColorArea provides an aria-label for the localized string "Color Picker",
which labels the visually hidden <input> elements for the two color channels. If you wish to override this with a more specific label, an aria-label or
aria-labelledby prop may be passed to further identify the element to assistive technologies.
For example, for a ColorArea that adjusts a background color you might pass the aria-label prop, "Background color". If you provide your own aria-label or aria-labelledby, be sure to localize the string appropriately.
<div style={{display: 'flex', gap: 8, alignItems: 'end', flexWrap: 'wrap'}}>
<MyColorArea
/*- begin highlight -*/
aria-label="Background color"
/*- end highlight -*/
defaultValue="hsl(0, 100%, 50%)"
xChannel="saturation"
yChannel="lightness" />
<div>
<label id="hsl-aria-labelledby-id">Background color</label>
<MyColorArea
/*- begin highlight -*/
aria-labelledby="hsl-aria-labelledby-id"
/*- end highlight -*/
defaultValue="hsl(0, 100%, 50%)"
xChannel="saturation"
yChannel="lightness" />
</div>
</div>
In order to communicate to a screen reader user that the ColorArea adjusts in two dimensions,
ColorArea provides an aria-roledescription, using the localized string "2D Slider", on each of the
visually hidden <input> elements.
The aria-valuetext of each <input> element within the ColorArea is formatted according to the user's locale automatically.
It will include the localized color channel name and current value for each channel, along with a localized description of the selected color (e.g. "dark vibrant blue").
In right-to-left languages, color areas should be mirrored.
Orientation of the gradient background, positioning of the thumb,
and dragging behavior is automatically mirrored by ColorArea.
The <ColorThumb> component renders a draggable thumb with a preview of the selected color.
React Aria components can be styled in many ways, including using CSS classes, inline styles, utility classes (e.g. Tailwind), CSS-in-JS (e.g. Styled Components), etc. By default, all components include a builtin className attribute which can be targeted using CSS selectors. These follow the react-aria-ComponentName naming convention.
.react-aria-ColorArea {
/* ... */
}
A custom className can also be specified on any component. This overrides the default className provided by React Aria with your own.
<ColorArea className="my-color-area">
</ColorArea>
In addition, some components support multiple UI states (e.g. focused, placeholder, readonly, etc.). React Aria components expose states using data attributes, which you can target in CSS selectors. For example:
.react-aria-ColorThumb[data-dragging] {
/* ... */
}
.react-aria-ColorThumb[data-focused] {
/* ... */
}
The className and style props also accept functions which receive states for styling. This lets you dynamically determine the classes or styles to apply, which is useful when using utility CSS libraries like Tailwind.
<ColorThumb className={({isDragging}) => isDragging ? 'scale-150' : 'scale-100'} />
The states, selectors, and render props for each component used in a ColorArea are documented below.
The ColorArea component can be targeted with the .react-aria-ColorArea CSS selector, or by overriding with a custom className. It supports the following states:
The ColorThumb component can be targeted with the .react-aria-ColorThumb CSS selector, or by overriding with a custom className. It supports the following states:
All React Aria Components export a corresponding context that can be used to send props to them from a parent element. This enables you to build your own compositional APIs similar to those found in React Aria Components itself. You can send any prop or ref via context that you could pass to the corresponding component. The local props and ref on the component are merged with the ones passed via context, with the local props taking precedence (following the rules documented in mergeProps).
<ContextTable components={['ColorArea']} docs={docs} />
This example shows a ColorAreaDescription component that accepts a color wheel in its children and renders a description element below it. It uses the useId hook to generate a unique id for the description, and associates it with the color wheel via the aria-describedby attribute passed to the ColorAreaContext provider.
import {ColorAreaContext} from 'react-aria-components';
import {useId} from 'react-aria';
interface ColorAreaDescriptionProps {
children?: React.ReactNode,
description?: string
}
function ColorAreaDescription({children, description}: ColorAreaDescriptionProps) {
let descriptionId = useId();
return (
<div>
<ColorAreaContext.Provider value={{'aria-describedby': descriptionId}}>
{children}
</ColorAreaContext.Provider>
<small id={descriptionId}>{description}</small>
</div>
);
}
<ColorAreaDescription description="Choose a background color for your profile.">
<MyColorArea />
</ColorAreaDescription>
ColorArea provides a <TypeLink links={statelyDocs.links} type={statelyDocs.exports.ColorAreaState} /> object to its children via ColorAreaStateContext. This can be used to access and manipulate the color area's state.
If you need to customize things even further, such as accessing internal state or customizing DOM structure, you can drop down to the lower level Hook-based API. See useColorArea for more details.