useColorWheel
Provides the behavior and accessibility implementation for a color wheel component. Color wheels allow users to adjust the hue of an HSL or HSB color value on a circular track.
install | yarn add @react-aria/color |
---|---|
version | 3.0.0-beta.26 |
usage | import {useColorWheel} from '@react-aria/color' |
API#
useColorWheel(
props: AriaColorWheelOptions,
state: ColorWheelState,
inputRef: RefObject<HTMLInputElement>
): ColorWheelAria
Features#
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 only a hue color wheel. useColorWheel
helps achieve accessible and
touch-friendly color wheels that can be styled as needed.
- Support for adjusting the hue of an HSL or HSB color value
- Support for mouse, touch, and keyboard via the useMove hook
- Multi-touch support
- Pressing on the track moves the thumb to that position
- Supports using the arrow keys, as well as page up/down, home, and end keys
- Support for disabling the color wheel
- Prevents text selection while dragging
- Exposed to assistive technology as a
slider
element via ARIA - Uses a hidden native input element to support touch screen readers
- Automatic ARIA labeling using the localized channel name by default
Anatomy#
A color wheel consists of a circular track and a thumb that the user can drag to change the color hue.
A visually hidden <input>
element is used to represent the value to assistive technologies.
useColorWheel
returns three sets of props that you should spread onto the appropriate elements:
Name | Type | Description |
trackProps | DOMAttributes | Props for the track element. |
thumbProps | DOMAttributes | Props for the thumb element. |
inputProps | InputHTMLAttributes<HTMLInputElement> | Props for the visually hidden range input element. |
State is managed by the useColorWheelState
hook from @react-stately/color
. The state object should be passed as an option to useColorWheel
By default, useColorWheel
provides an aria-label
for the localized string "Hue". If you wish to override this
with a more specific label, an aria-label
or aria-labelledby
prop may be passed instead to identify the element
to assistive technologies.
Example#
This example shows how to build a simple color wheel with a draggable thumb to adjust the hue value of a color. Styling for
the track background and positioning of the thumb are provided by useColorWheel
in the returned style
prop for each element.
The <input>
element inside the thumb is used to represent the color wheel to assistive technology, and is hidden from view
using the VisuallyHidden component. The thumb also uses the useFocusRing hook to
grow in size when it is keyboard focused (try tabbing to it).
import {useColorWheel} from '@react-aria/color';
import {useColorWheelState} from '@react-stately/color';
import {VisuallyHidden} from '@react-aria/visually-hidden';
import {useFocusRing} from '@react-aria/focus';
const RADIUS = 100;
const TRACK_THICKNESS = 28;
const THUMB_SIZE = 20;
function ColorWheel(props) {
let state = useColorWheelState(props);
let inputRef = React.useRef(null);
let {trackProps, inputProps, thumbProps} = useColorWheel({
...props,
outerRadius: RADIUS,
innerRadius: RADIUS - TRACK_THICKNESS
}, state, inputRef);
let {focusProps, isFocusVisible} = useFocusRing();
return (
<div style={{position: 'relative', display: 'inline-block'}}>
<div {...trackProps} />
<div
{...thumbProps}
style={{
...thumbProps.style,
border: '2px solid white',
boxShadow: '0 0 0 1px black, inset 0 0 0 1px black',
width: isFocusVisible ? TRACK_THICKNESS + 4 : THUMB_SIZE,
height: isFocusVisible ? TRACK_THICKNESS + 4 : THUMB_SIZE,
borderRadius: '50%',
boxSizing: 'border-box'
}}>
<VisuallyHidden>
<input {...inputProps} {...focusProps} ref={inputRef} />
</VisuallyHidden>
</div>
</div>
);
}
<ColorWheel />
import {useColorWheel} from '@react-aria/color';
import {useColorWheelState} from '@react-stately/color';
import {VisuallyHidden} from '@react-aria/visually-hidden';
import {useFocusRing} from '@react-aria/focus';
const RADIUS = 100;
const TRACK_THICKNESS = 28;
const THUMB_SIZE = 20;
function ColorWheel(props) {
let state = useColorWheelState(props);
let inputRef = React.useRef(null);
let { trackProps, inputProps, thumbProps } =
useColorWheel(
{
...props,
outerRadius: RADIUS,
innerRadius: RADIUS - TRACK_THICKNESS
},
state,
inputRef
);
let { focusProps, isFocusVisible } = useFocusRing();
return (
<div
style={{
position: 'relative',
display: 'inline-block'
}}
>
<div {...trackProps} />
<div
{...thumbProps}
style={{
...thumbProps.style,
border: '2px solid white',
boxShadow:
'0 0 0 1px black, inset 0 0 0 1px black',
width: isFocusVisible
? TRACK_THICKNESS + 4
: THUMB_SIZE,
height: isFocusVisible
? TRACK_THICKNESS + 4
: THUMB_SIZE,
borderRadius: '50%',
boxSizing: 'border-box'
}}
>
<VisuallyHidden>
<input
{...inputProps}
{...focusProps}
ref={inputRef}
/>
</VisuallyHidden>
</div>
</div>
);
}
<ColorWheel />
import {useColorWheel} from '@react-aria/color';
import {useColorWheelState} from '@react-stately/color';
import {VisuallyHidden} from '@react-aria/visually-hidden';
import {useFocusRing} from '@react-aria/focus';
const RADIUS = 100;
const TRACK_THICKNESS =
28;
const THUMB_SIZE = 20;
function ColorWheel(
props
) {
let state =
useColorWheelState(
props
);
let inputRef = React
.useRef(null);
let {
trackProps,
inputProps,
thumbProps
} = useColorWheel(
{
...props,
outerRadius:
RADIUS,
innerRadius:
RADIUS -
TRACK_THICKNESS
},
state,
inputRef
);
let {
focusProps,
isFocusVisible
} = useFocusRing();
return (
<div
style={{
position:
'relative',
display:
'inline-block'
}}
>
<div
{...trackProps}
/>
<div
{...thumbProps}
style={{
...thumbProps
.style,
border:
'2px solid white',
boxShadow:
'0 0 0 1px black, inset 0 0 0 1px black',
width:
isFocusVisible
? TRACK_THICKNESS +
4
: THUMB_SIZE,
height:
isFocusVisible
? TRACK_THICKNESS +
4
: THUMB_SIZE,
borderRadius:
'50%',
boxSizing:
'border-box'
}}
>
<VisuallyHidden>
<input
{...inputProps}
{...focusProps}
ref={inputRef}
/>
</VisuallyHidden>
</div>
</div>
);
}
<ColorWheel />
Usage#
The following examples show how to use the ColorWheel
component created in the above example.
Uncontrolled#
By default, ColorWheel
is uncontrolled with a default value of red (hue = 0˚). You can change the
default value using the defaultValue
prop.
<ColorWheel defaultValue="hsl(80, 100%, 50%)" />
<ColorWheel defaultValue="hsl(80, 100%, 50%)" />
<ColorWheel defaultValue="hsl(80, 100%, 50%)" />
Controlled#
A ColorWheel
can be made controlled using the value
prop. The parseColor
function is used to parse the initial color from an HSL string, stored in state. The onChange
prop
is used to update the value in state when the user drags the thumb.
import {parseColor} from '@react-stately/color';
function Example() {
let [color, setColor] = React.useState(parseColor('hsl(0, 100%, 50%)'));
return (
<>
<ColorWheel value={color} onChange={setColor} />
<p>Current color value: {color.toString('hsl')}</p>
</>
);
}
import {parseColor} from '@react-stately/color';
function Example() {
let [color, setColor] = React.useState(
parseColor('hsl(0, 100%, 50%)')
);
return (
<>
<ColorWheel value={color} onChange={setColor} />
<p>Current color value: {color.toString('hsl')}</p>
</>
);
}
import {parseColor} from '@react-stately/color';
function Example() {
let [color, setColor] =
React.useState(
parseColor(
'hsl(0, 100%, 50%)'
)
);
return (
<>
<ColorWheel
value={color}
onChange={setColor}
/>
<p>
Current color
value:{' '}
{color.toString(
'hsl'
)}
</p>
</>
);
}
onChangeEnd#
The onChangeEnd
prop can be used to handle when a user stops dragging the color wheel, whereas the onChange
prop is called as the user drags.
function Example() {
let [color, setColor] = React.useState(parseColor('hsl(0, 100%, 50%)'));
return (
<>
<ColorWheel defaultValue={color} onChangeEnd={setColor} />
<p>Current color value: {color.toString('hsl')}</p>
</>
);
}
function Example() {
let [color, setColor] = React.useState(
parseColor('hsl(0, 100%, 50%)')
);
return (
<>
<ColorWheel
defaultValue={color}
onChangeEnd={setColor}
/>
<p>Current color value: {color.toString('hsl')}</p>
</>
);
}
function Example() {
let [color, setColor] =
React.useState(
parseColor(
'hsl(0, 100%, 50%)'
)
);
return (
<>
<ColorWheel
defaultValue={color}
onChangeEnd={setColor}
/>
<p>
Current color
value:{' '}
{color.toString(
'hsl'
)}
</p>
</>
);
}
Disabled#
A ColorWheel
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 wheel to appear disabled accordingly.
<ColorWheel defaultValue="hsl(80, 100%, 50%)" isDisabled />
<ColorWheel defaultValue="hsl(80, 100%, 50%)" isDisabled />
<ColorWheel
defaultValue="hsl(80, 100%, 50%)"
isDisabled
/>
HTML forms#
ColorWheel supports the name
prop for integration with HTML forms. The value will be submitted as a number between 0 and 360 degrees.
<ColorWheel name="hue" />
<ColorWheel name="hue" />
<ColorWheel name="hue" />
Internationalization#
Labeling#
By default, a localized string for the "hue" channel name is used as the aria-label
for the ColorWheel
. When a custom aria-label
is provided, it should be localized accordingly. To get a localized channel name to use as a visual label,
you can use the color.getChannelName
method.
Value formatting#
The aria-valuetext
of the <input>
element is formatted according to the user's locale automatically. If you wish to display this
value visually, you can use the color.formatChannelValue
method.
RTL#
Color wheels should not be mirrored in right-to-left languages.