27 lines
1.1 KiB
JavaScript
27 lines
1.1 KiB
JavaScript
/** @typedef {import('window').IntersectionObserverCallback} IntersectionObserverCallback */
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/**
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* Util that returns an IntersectionObserver if supported by the browser. If
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* it's not supported, it returns a shim object with the methods to prevent JS
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* errors. Notice it's a shim, not a polyfill. If the browser doesn't support
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* IntersectionObserver, the methods returned by this function will do nothing.
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*
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* @param {IntersectionObserverCallback} callback Callback function for the
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* Intersection Observer.
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* @param {Object} options Intersection Observer options.
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* @return {Object|IntersectionObserver} Intersection Observer if available,
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* otherwise a shim object.
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*
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* @todo Remove IntersectionObserver shim when we drop IE11 support.
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*/
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export const getIntersectionObserver = ( callback, options ) => {
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if ( typeof IntersectionObserver !== 'function' ) {
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return {
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observe: () => void null,
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unobserve: () => void null,
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};
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}
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return new IntersectionObserver( callback, options );
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};
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