masto-fe/app/javascript/mastodon/components/modal_root.js
ThibG 35b142a7ad Fix lost focus when modals open/close (#12437)
* Fix lost focus after modal closes

Regression caused by the use of the wicg-inert polyfill

* Fix regression introduced by wicg-inert

* Catch errors to please CodeClimate
2019-11-30 18:19:47 +01:00

116 lines
3.3 KiB
JavaScript

import React from 'react';
import PropTypes from 'prop-types';
import 'wicg-inert';
export default class ModalRoot extends React.PureComponent {
static propTypes = {
children: PropTypes.node,
onClose: PropTypes.func.isRequired,
};
state = {
revealed: !!this.props.children,
};
activeElement = this.state.revealed ? document.activeElement : null;
handleKeyUp = (e) => {
if ((e.key === 'Escape' || e.key === 'Esc' || e.keyCode === 27)
&& !!this.props.children) {
this.props.onClose();
}
}
handleKeyDown = (e) => {
if (e.key === 'Tab') {
const focusable = Array.from(this.node.querySelectorAll('button:not([disabled]), [href], input:not([disabled]), select:not([disabled]), textarea:not([disabled]), [tabindex]:not([tabindex="-1"])')).filter((x) => window.getComputedStyle(x).display !== 'none');
const index = focusable.indexOf(e.target);
let element;
if (e.shiftKey) {
element = focusable[index - 1] || focusable[focusable.length - 1];
} else {
element = focusable[index + 1] || focusable[0];
}
if (element) {
element.focus();
e.stopPropagation();
e.preventDefault();
}
}
}
componentDidMount () {
window.addEventListener('keyup', this.handleKeyUp, false);
window.addEventListener('keydown', this.handleKeyDown, false);
}
componentWillReceiveProps (nextProps) {
if (!!nextProps.children && !this.props.children) {
this.activeElement = document.activeElement;
this.getSiblings().forEach(sibling => sibling.setAttribute('inert', true));
} else if (!nextProps.children) {
this.setState({ revealed: false });
}
}
componentDidUpdate (prevProps) {
if (!this.props.children && !!prevProps.children) {
this.getSiblings().forEach(sibling => sibling.removeAttribute('inert'));
// Because of the wicg-inert polyfill, the activeElement may not be
// immediately selectable, we have to wait for observers to run, as
// described in https://github.com/WICG/inert#performance-and-gotchas
Promise.resolve().then(() => {
this.activeElement.focus();
this.activeElement = null;
}).catch((error) => {
console.error(error);
});
}
if (this.props.children) {
requestAnimationFrame(() => {
this.setState({ revealed: true });
});
}
}
componentWillUnmount () {
window.removeEventListener('keyup', this.handleKeyUp);
window.removeEventListener('keydown', this.handleKeyDown);
}
getSiblings = () => {
return Array(...this.node.parentElement.childNodes).filter(node => node !== this.node);
}
setRef = ref => {
this.node = ref;
}
render () {
const { children, onClose } = this.props;
const { revealed } = this.state;
const visible = !!children;
if (!visible) {
return (
<div className='modal-root' ref={this.setRef} style={{ opacity: 0 }} />
);
}
return (
<div className='modal-root' ref={this.setRef} style={{ opacity: revealed ? 1 : 0 }}>
<div style={{ pointerEvents: visible ? 'auto' : 'none' }}>
<div role='presentation' className='modal-root__overlay' onClick={onClose} />
<div role='dialog' className='modal-root__container'>{children}</div>
</div>
</div>
);
}
}