Description
To ensure that content the requires it (modals, menus, etc) can escape overflow rules, the z-index, et al, Spectrum Web Components provides an overlay system that is made up of three interrelated elements, <overlay-trigger>
, <active-overlay>
, and <sp-theme>
. DOM that should be overlaid on hover ([slot="hover-content"]
) and click ([slot="click-content"]
) are outlined in the light DOM content of an <overlay-trigger>
. Said content will be overlayed onto the DOM via an <active-overlay>
element that will be appended to the <body>
. Content delivered in this way will acquire CSS Custom Properties for color
and size
from the trigger's nearest ancestor <sp-theme>
.
Note: Cascading styles not applied via <sp-theme>
are not currently projected along with the overlay content. To ensure that any additionoal styles for the overlaid content are applied, use the style
attribute directly or encapsulate this content in a custom element that applies its styles via shadow DOM.
Usage
yarn add @spectrum-web-components/overlay
Import the side effectful registration of <active-overlay>
or <overlay-trigger>
via:
import '@spectrum-web-components/overlay/active-overlay.js';
import '@spectrum-web-components/overlay/overlay-trigger.js';
The default of <overlay-trigger>
will load various dependencies asynchronously via a dynamic import. In the case that you would like to import those tranverse dependencies statically, import the side effectful registration of <overlay-trigger>
as follows:
import '@spectrum-web-components/overlay/sync/overlay-trigger.js';
When looking to leverage the ActiveOverlay
or OverlayTrigger
base class as a type and/or for extension purposes, do so via:
import {
ActiveOverlay,
OverlayTrigger
} from '@spectrum-web-components/overlay';
Example
<style>
overlay-trigger {
flex: none;
}
.tooltip {
background-color: var(--spectrum-global-color-gray-800);
color: var(--spectrum-global-color-gray-50);
padding: 4px 10px;
font-size: 10px;
}
</style>
<overlay-trigger id="trigger" placement="bottom" offset="6">
<sp-button variant="primary" slot="trigger">
Button popover
</sp-button>
<sp-popover dialog slot="click-content" direction="bottom" tip open>
<div class="options-popover-content">
<sp-slider
value="5"
step="0.5"
min="0"
max="20"
label="Awesomeness"
></sp-slider>
<sp-button>Press me</sp-button>
</div>
</sp-popover>
<sp-tooltip slot="hover-content" delayed open>
Tooltip
</sp-tooltip>
</overlay-trigger>
Accessibility
When using an <overlay-trigger>
element, it is important to be sure the that content you project into slot="trigger"
is "interactive". This means that an element within that branch of DOM will be able to receive focus and said element will appropriately convert keyboard interactions to click
events similar to what you find with <a href="#">Anchors</a>
, <button>Buttons</button>
, etc. You can find further reading on the subject of accessible keyboard interactions at https://www.w3.org/WAI/WCAG21/Understanding/keyboard.