hometown/app/javascript/mastodon/components/status_list.js
Sorin Davidoi 534da4f24f Improve accessibility (part 5) (#4417)
* fix(status): Add tabIndex=0

* fix(status_list): Make keyboard navigable
2017-07-28 13:33:40 +02:00

173 lines
5.1 KiB
JavaScript

import React from 'react';
import ImmutablePropTypes from 'react-immutable-proptypes';
import { ScrollContainer } from 'react-router-scroll';
import PropTypes from 'prop-types';
import StatusContainer from '../containers/status_container';
import LoadMore from './load_more';
import ImmutablePureComponent from 'react-immutable-pure-component';
import IntersectionObserverWrapper from '../features/ui/util/intersection_observer_wrapper';
import { throttle } from 'lodash';
export default class StatusList extends ImmutablePureComponent {
static propTypes = {
scrollKey: PropTypes.string.isRequired,
statusIds: ImmutablePropTypes.list.isRequired,
onScrollToBottom: PropTypes.func,
onScrollToTop: PropTypes.func,
onScroll: PropTypes.func,
trackScroll: PropTypes.bool,
shouldUpdateScroll: PropTypes.func,
isLoading: PropTypes.bool,
hasMore: PropTypes.bool,
prepend: PropTypes.node,
emptyMessage: PropTypes.node,
};
static defaultProps = {
trackScroll: true,
};
intersectionObserverWrapper = new IntersectionObserverWrapper();
handleScroll = throttle(() => {
if (this.node) {
const { scrollTop, scrollHeight, clientHeight } = this.node;
const offset = scrollHeight - scrollTop - clientHeight;
this._oldScrollPosition = scrollHeight - scrollTop;
if (400 > offset && this.props.onScrollToBottom && !this.props.isLoading) {
this.props.onScrollToBottom();
} else if (scrollTop < 100 && this.props.onScrollToTop) {
this.props.onScrollToTop();
} else if (this.props.onScroll) {
this.props.onScroll();
}
}
}, 150, {
trailing: true,
});
componentDidMount () {
this.attachScrollListener();
this.attachIntersectionObserver();
// Handle initial scroll posiiton
this.handleScroll();
}
componentDidUpdate (prevProps) {
// Reset the scroll position when a new toot comes in in order not to
// jerk the scrollbar around if you're already scrolled down the page.
if (prevProps.statusIds.size < this.props.statusIds.size && this._oldScrollPosition && this.node.scrollTop > 0) {
if (prevProps.statusIds.first() !== this.props.statusIds.first()) {
let newScrollTop = this.node.scrollHeight - this._oldScrollPosition;
if (this.node.scrollTop !== newScrollTop) {
this.node.scrollTop = newScrollTop;
}
} else {
this._oldScrollPosition = this.node.scrollHeight - this.node.scrollTop;
}
}
}
componentWillUnmount () {
this.detachScrollListener();
this.detachIntersectionObserver();
}
attachIntersectionObserver () {
this.intersectionObserverWrapper.connect({
root: this.node,
rootMargin: '300% 0px',
});
}
detachIntersectionObserver () {
this.intersectionObserverWrapper.disconnect();
}
attachScrollListener () {
this.node.addEventListener('scroll', this.handleScroll);
}
detachScrollListener () {
this.node.removeEventListener('scroll', this.handleScroll);
}
setRef = (c) => {
this.node = c;
}
handleLoadMore = (e) => {
e.preventDefault();
this.props.onScrollToBottom();
}
handleKeyDown = (e) => {
if (['PageDown', 'PageUp', 'End', 'Home'].includes(e.key)) {
const article = (() => {
switch (e.key) {
case 'PageDown':
return e.nativeEvent.path[0].nodeName === 'ARTICLE' && e.nativeEvent.path[0].nextElementSibling;
case 'PageUp':
return e.nativeEvent.path[0].nodeName === 'ARTICLE' && e.nativeEvent.path[0].previousElementSibling;
case 'End':
return this.node.querySelector('[role="feed"] > article:last-of-type');
case 'Home':
return this.node.querySelector('[role="feed"] > article:first-of-type');
default:
return null;
}
})();
if (article) {
e.preventDefault();
article.focus();
article.scrollIntoView();
}
}
}
render () {
const { statusIds, scrollKey, trackScroll, shouldUpdateScroll, isLoading, hasMore, prepend, emptyMessage } = this.props;
const loadMore = <LoadMore visible={!isLoading && statusIds.size > 0 && hasMore} onClick={this.handleLoadMore} />;
let scrollableArea = null;
if (isLoading || statusIds.size > 0 || !emptyMessage) {
scrollableArea = (
<div className='scrollable' ref={this.setRef}>
<div role='feed' className='status-list' onKeyDown={this.handleKeyDown}>
{prepend}
{statusIds.map((statusId, index) => {
return <StatusContainer key={statusId} id={statusId} index={index} listLength={statusIds.size} intersectionObserverWrapper={this.intersectionObserverWrapper} />;
})}
{loadMore}
</div>
</div>
);
} else {
scrollableArea = (
<div className='empty-column-indicator' ref={this.setRef}>
{emptyMessage}
</div>
);
}
if (trackScroll) {
return (
<ScrollContainer scrollKey={scrollKey} shouldUpdateScroll={shouldUpdateScroll}>
{scrollableArea}
</ScrollContainer>
);
} else {
return scrollableArea;
}
}
}