diff options
| -rw-r--r-- | app/javascript/flavours/glitch/components/intersection_observer_article.js | 26 |
1 files changed, 12 insertions, 14 deletions
diff --git a/app/javascript/flavours/glitch/components/intersection_observer_article.js b/app/javascript/flavours/glitch/components/intersection_observer_article.js index 8b06f9a8c..f7f6b0a53 100644 --- a/app/javascript/flavours/glitch/components/intersection_observer_article.js +++ b/app/javascript/flavours/glitch/components/intersection_observer_article.js @@ -1,15 +1,10 @@ import React from 'react'; import PropTypes from 'prop-types'; +import ImmutablePureComponent from 'react-immutable-pure-component'; import scheduleIdleTask from 'flavours/glitch/util/schedule_idle_task'; import getRectFromEntry from 'flavours/glitch/util/get_rect_from_entry'; -import { is } from 'immutable'; -// Diff these props in the "rendered" state -const updateOnPropsForRendered = ['id', 'index', 'listLength']; -// Diff these props in the "unrendered" state -const updateOnPropsForUnrendered = ['id', 'index', 'listLength', 'cachedHeight']; - -export default class IntersectionObserverArticle extends React.Component { +export default class IntersectionObserverArticle extends ImmutablePureComponent { static propTypes = { intersectionObserverWrapper: PropTypes.object.isRequired, @@ -27,15 +22,18 @@ export default class IntersectionObserverArticle extends React.Component { } shouldComponentUpdate (nextProps, nextState) { - const isUnrendered = !this.state.isIntersecting && (this.state.isHidden || this.props.cachedHeight); - const willBeUnrendered = !nextState.isIntersecting && (nextState.isHidden || nextProps.cachedHeight); - if (!!isUnrendered !== !!willBeUnrendered) { - // If we're going from rendered to unrendered (or vice versa) then update + if (!nextState.isIntersecting && nextState.isHidden) { + // It's only if we're not intersecting (i.e. offscreen) and isHidden is true + // that either "isIntersecting" or "isHidden" matter, and then they're + // the only things that matter (and updated ARIA attributes). + return this.state.isIntersecting || !this.state.isHidden || nextProps.listLength !== this.props.listLength; + } else if (nextState.isIntersecting && !this.state.isIntersecting) { + // If we're going from a non-intersecting state to an intersecting state, + // (i.e. offscreen to onscreen), then we definitely need to re-render return true; } - // Otherwise, diff based on props - const propsToDiff = isUnrendered ? updateOnPropsForUnrendered : updateOnPropsForRendered; - return !propsToDiff.every(prop => is(nextProps[prop], this.props[prop])); + // Otherwise, diff based on "updateOnProps" and "updateOnStates" + return super.shouldComponentUpdate(nextProps, nextState); } componentDidMount () { |