34 lines
1.4 KiB
JavaScript
34 lines
1.4 KiB
JavaScript
import ResizeObserver from 'resize-observer-polyfill';
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// =============================== Const ===============================
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var elementListeners = new Map();
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function onResize(entities) {
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entities.forEach(function (entity) {
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var _elementListeners$get;
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var target = entity.target;
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(_elementListeners$get = elementListeners.get(target)) === null || _elementListeners$get === void 0 ? void 0 : _elementListeners$get.forEach(function (listener) {
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return listener(target);
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});
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});
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}
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// Note: ResizeObserver polyfill not support option to measure border-box resize
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var resizeObserver = new ResizeObserver(onResize);
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// Dev env only
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export var _el = process.env.NODE_ENV !== 'production' ? elementListeners : null; // eslint-disable-line
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export var _rs = process.env.NODE_ENV !== 'production' ? onResize : null; // eslint-disable-line
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// ============================== Observe ==============================
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export function observe(element, callback) {
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if (!elementListeners.has(element)) {
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elementListeners.set(element, new Set());
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resizeObserver.observe(element);
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}
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elementListeners.get(element).add(callback);
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}
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export function unobserve(element, callback) {
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if (elementListeners.has(element)) {
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elementListeners.get(element).delete(callback);
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if (!elementListeners.get(element).size) {
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resizeObserver.unobserve(element);
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elementListeners.delete(element);
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}
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}
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} |