19 lines
578 B
Plaintext
19 lines
578 B
Plaintext
import isBrowser from '../../../utils/isBrowser';
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import isDocumentVisible from './isDocumentVisible';
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var listeners = new Set();
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function subscribe(listener) {
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listeners.add(listener);
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return function unsubscribe() {
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listeners.has(listener) && listeners.delete(listener);
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};
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}
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if (isBrowser) {
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var revalidate = function () {
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if (!isDocumentVisible())
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return;
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listeners.forEach(function (listener) { return listener(); });
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};
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window.addEventListener('visibilitychange', revalidate, false);
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}
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export default subscribe;
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