Improve IntersectionObserverArticle perf (#5152)

This commit is contained in:
Nolan Lawson 2017-09-30 05:28:49 -07:00 committed by Eugen Rochko
parent 83ffc4dc07
commit ca0e8be20c

View File

@ -58,26 +58,31 @@ export default class IntersectionObserverArticle extends React.Component {
}
handleIntersection = (entry) => {
const { onHeightChange, saveHeightKey, id } = this.props;
this.entry = entry;
if (this.node && this.node.children.length !== 0) {
// save the height of the fully-rendered element
this.height = getRectFromEntry(entry).height;
scheduleIdleTask(this.calculateHeight);
this.setState(this.updateStateAfterIntersection);
}
if (onHeightChange && saveHeightKey) {
onHeightChange(saveHeightKey, id, this.height);
}
updateStateAfterIntersection = (prevState) => {
if (prevState.isIntersecting && !this.entry.isIntersecting) {
scheduleIdleTask(this.hideIfNotIntersecting);
}
return {
isIntersecting: this.entry.isIntersecting,
isHidden: false,
};
}
this.setState((prevState) => {
if (prevState.isIntersecting && !entry.isIntersecting) {
scheduleIdleTask(this.hideIfNotIntersecting);
}
return {
isIntersecting: entry.isIntersecting,
isHidden: false,
};
});
calculateHeight = () => {
const { onHeightChange, saveHeightKey, id } = this.props;
// save the height of the fully-rendered element (this is expensive
// on Chrome, where we need to fall back to getBoundingClientRect)
this.height = getRectFromEntry(this.entry).height;
if (onHeightChange && saveHeightKey) {
onHeightChange(saveHeightKey, id, this.height);
}
}
hideIfNotIntersecting = () => {