File size: 2,277 Bytes
1e92f2d |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 |
import { useEffect } from 'react';
/*
* React component that manages `is-section-*` and `is-group-*` class names on the <body>
* element. When the `section` and `group` props get updated, it adds, removes and replaces
* CSS classes accordingly.
*
* TODO: reconsider if these classnames are really needed on <body> and whether having them
* on `div.layout` could be sufficient to satisfy all theming and styling requirements.
* `div.layout` has the advantage of being maintained by React, where class names can be
* specified declaratively and the DOM diffing and patching is done by React itself.
*/
function useBodyClass( prefix, value ) {
useEffect( () => {
// if value is empty-ish, don't add or remove any CSS classes
if ( ! value ) {
return;
}
// Remove any existing classes with the same prefix, coming from example from a
// server HTML markup. There should be max one class name with a gived `prefix`
// at any one time. We're removing existing classes only when `value` is not `null`,
// i.e., when we actually have a class name to add and want to prevent duplicate one.
for ( const className of document.body.classList ) {
if ( className.startsWith( prefix ) ) {
document.body.classList.remove( className );
}
}
// convert the value (section or group name) to a CSS class name
const className = prefix + value;
// add the CSS class to body when performing the effect
document.body.classList.add( className );
// remove the CSS class from body in the effect cleanup function
return () => document.body.classList.remove( className );
}, [ prefix, value ] );
}
/**
* @param {{group?: string, section?: string, bodyClass?: string[]}} props
*/
export default function BodySectionCssClass( { group, section, layoutFocus, bodyClass } ) {
useBodyClass( 'is-group-', group );
useBodyClass( 'is-section-', section );
useBodyClass( 'is-focus-', layoutFocus );
useEffect( () => {
if ( ! Array.isArray( bodyClass ) || bodyClass.length === 0 ) {
return;
}
bodyClass.forEach( ( className ) => {
document.body.classList.add( className );
} );
return () => {
bodyClass.forEach( ( className ) => {
document.body.classList.remove( className );
} );
};
}, [ bodyClass ] );
return null;
}
|