`<sp-slider>` allows users to quickly select a value within a range. They should be used when the upper and lower bounds of the range are invariable.
npm install @spectrum-web-components/slider
``
yarn add @spectrum-web-components/slider
Import the side effectful registration of via:
`
import '@spectrum-web-components/slider/sp-slider.js';
When leveraging the editable attribute, the @spectrum-web-components/number-field/sp-number-field.js dependency will be asynchronously loaded via a dynamic import to reduce JS payload for applications not leveraging this feature. In the case that you would like to import those transverse dependencies statically, import the side effectful registration of as follows:
`
import '@spectrum-web-components/slider/sync/sp-slider.js';
When looking to leverage the Slider base class as a type and/or for extension purposes, do so via:
`
import { Slider } from '@spectrum-web-components/slider';
`html`
#### Label visibility
By default, an element has both a "text" label and a "value" label. The "value" label is output by the element itself based on its state, but the "text" label must be supplied by the consuming developer in order for the to be delivered in an accessible manner.
Either or both of these can be suppressed visually as needed by your application UI, while still fulfilling their role in delivering a quality accessibility tree to the browser. This delivery is controlled by the label-visibility attribute (or labelVisibility property) which accepts text, value, or none as values.
Use label-visibility="text" to suppress the "value" label, use label-visibility="value" to suppress the "text" label, or use label-visibility="none" to suppress the "text" label. In each case outlined above the content for both labels will be made available to screen readers, so be sure to manage the content delivered to visitors in that context.
`html`
label-visibility="text"
value="50"
>
`html`
`html`
#### Handle slot
The slider also optionally accepts two or more elements with slot="handle":
`html`
Output Levels
name="low"
label="Low"
value="5"
max="next"
>
name="mid"
label="Mid"
value="100"
min="previous"
max="next"
>
name="high"
label="High"
value="250"
min="previous"
>
#### Sizes
`html`
`html`
`html`
`html`
#### Editable
An element can be paired with an element via the editable attribute. The will be passed all of the standard options from the element (e.g. min, max, formatOptions, etc.) and will also accept the hide-stepper attribute in order to prevent the display of its stepper UI.
The quiet attribute applies Quiet styling to the number field when a slider is editable.
`html`
editable
max="24"
min="0"
value="7.25"
step="0.25"
style="--spectrum-slider-editable-number-field-width: 100px;"
format-options='{
"style": "unit",
"unit": "hour"
}'
>
`html`
editable
hide-stepper
min="0"
max="360"
format-options='{
"style": "unit",
"unit": "degree",
"unitDisplay": "narrow"
}'
>
`html`
#### Filled
Use variant="filled" to add a filled style to the slider from a starting point to the current value. By default the starting point is the min value.
`html`
max="1"
variant="filled"
min="0"
value=".5"
step="0.01"
>
max="1"
variant="filled"
min="0"
value=".5"
step="0.01"
disabled
>
##### fill-start
When both fill-start and variant="filled" are used in , the fill-start property defines the starting point. If fill start does not have a number associated with it, the starting point will be the value.
Any number (including 0) can be used as a fill-start value. If a custom normalization function is provided, it will also normalize all fill-related params.
`html`
max="1"
fill-start
variant="filled"
min="0"
value=".5"
step="0.01"
>
max="1"
fill-start
variant="filled"
min="0"
value=".8"
step="0.01"
disabled
>
`html`
label="fill-start greater than value"
max="1"
min="0"
value=".3"
step="0.1"
fill-start="0.7"
variant="filled"
>
`html`
label="Fill Start less than Value"
max="1"
min="0"
value=".7"
step="0.1"
fill-start="0.25"
variant="filled"
>
`html`
max="1"
min="-1"
value=".7"
step="0.1"
fill-start="0"
variant="filled"
>
#### Tick
With variant="tick", ticks are applied at intervals defined with the tick-step attribute. The tick-labels attribute will apply labels to the ticks.
`html`
variant="tick"
tick-step="5"
disabled
>
`html`
variant="tick"
tick-step="5"
tick-labels
>
variant="tick"
tick-step="5"
tick-labels
disabled
>
#### Ramp
With variant="ramp", the slider with increases as it approaches the max position.
`html`
The "range" variant along with two handles to create a range slider. (See slider handle.)
`html`
Output Levels
name="min"
label="Minimum"
value="5"
>
name="max"
label="Maximum"
value="250"
>
#### Format options for labels
An or element will process its numeric value with new Intl.NumberFormat(this.resolvedLanguage, this.formatOptions).format(this.value) in order to prepare it for visual delivery in the input. In order to customize this processing supply your own Intl.NumberFormatOptions via the formatOptions property, or format-options attribute as seen below.
this.resolvedLanguage represents the language in which the or element is currently being delivered. By default, this value will represent the language established by the lang attribute on the root element while falling back to navigator.language when that is not present. This value can be customized via a language context provided by a parent element that listens for the sp-language-context event and supplies updated language settings to the callback function contained therein. Applications leveraging the element to manage the visual delivery or text direction of their content will also be provided a reactive context for supplying language information to its descendants.
`html`
max="1"
step="0.01"
value="0.5"
label="Slider Label"
format-options='{
"style": "percent"
}'
>
More advanced formatting is available by specifying a formatting function to
the getAriaHandleText property on an sp-slider or sp-slider-handle. Or,getAriaValueText
for a multi-handle slider, you can format the combined value label for all
handles by passing a formatting function to the propertysp-slider
on the parent .
##### Units not included in Intl.NumberFormatOptions
While Intl.NumberFormatOptions does support a wide range of units, it is possible to encounter units (e.g. the graphics units of pixel, pixels, points, etc.) that are not supported therein. When this occurs, an element will attempt to polyfill support for this unit. See the following example delivering { style: "unit", unit: "px" } below:
`html`
value="500"
format-options='{
"style": "unit",
"unit": "px"
}'
>
Document width in pixels
Note: the polyfilling done here is very simplistic and is triggered by supplying options that would otherwise cause the Intl.NumberFormat() call to throw an error. Once the unsupporting unit of px causes the construction of the object to throw, a backup formatter/parser pair will be created without the supplied unit data. When the style is set to unit, the unit value will be adopted as the _static_ unit display. This means that neither pluralization nor translation will be handled within the element itself. If pluralization or translation is important to the delivered interface, please be sure to handle passing those strings into to element via the formatOptions property reactively to the value of the element or locale of that page in question.
#### Default value
Slider will reset to its default-value when the user double clicks on the slider handle or if the user presses the escape key when the slider handle is focused.
`html`
Note: If a slider with default-value attribute is contained in a modal and the slider handle is focused then the following interaction will occur on pressing the escape key:
- If the slider value is different from the default value then the slider value will be reset to the default value and the modal will not be closed.
- If the slider value is equal to the default value then the modal will be closed.
#### Advanced normalization
By default, sp-slider assumes a linear scale between the min and max values.
For advanced applications, it is sometimes necessary to specify a custom
"normalization."
Normalization is the process of converting a slider to a value between 0 and 1 where
0 represents the minimum and 1 represents the maximum. See the "Three Handles Complex" example in the playground.
#### Disabled
`html`
#### Indeterminate
The indeterminate attribute will be passed to the internal element and alter its visual delivery until a change has been made to the element at which point the change event that is dispatched can be understood as always removing the indeterminate attribute from the .
`html`
Like the element after which the is fashioned, it will dispatch input events in a stream culminating with a change event (representing the final commit of the value to the element) once the user has finished interacting with the element. Both other these events can access the value of their dispatching target via event.target.value. In this way, a steaming listener pattern similar to the following can prove useful:
`javascript
const slider = document.querySelector('sp-slider');
const endListener = ({ target }) => {
target.addEventListener('input', startListener);
target.removeEventListener('input', streamListener);
target.removeEventListener('change', endListener);
console.log(target.value);
};
const streamListener = ({ target }) => {
console.log(target.value);
};
const startListener = ({ target }) => {
target.removeEventListener('input', startListener);
target.addEventListener('input', streamListener);
target.addEventListener('change', endListener);
console.log(target.value);
};
slider.addEventListener('input', startListener);
`
#### Include labels
Every slider should have a label. A slider without a label is ambiguous and not accessible. Write the label in sentence case.
In rare cases where context is sufficient and a label doesn't require visibility, make sure to have the design reviewed and approved by an accessibility expert. Use label-visibility to set which labels should remain visible, and non-visible labels will still be read by assistive technology.
#### Keyboard navigation
The Tab and Shift+Tab keys are used to navigate to and set focus on the slider control. The Arrow Up (↑) and Arrow Down (↓) keys are used to increment the slider value, respectively.
Because multiple sliders are often used on the same page, the number field in the editable slider is designed to not be keyboard focusable via Tab or Shift+Tab keys. (See WAI ARIA APG's Keyboard Navigation Inside Components.) Since the slider itself can already be incremented via the arrow keys, a roving tabindex controller cannot be used within the slider; therefore, the number field will not be keyboard navigable.
Review the accessibility guidelines for the slider handle.