37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
/**
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* Limits the invocations of a function in a given time frame.
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*
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* The debounce function wrapper should be used sparingly. One clear use case
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* is limiting the invocation of a callback attached to the window resize event.
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*
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* Before using the debounce function wrapper, consider first whether the
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* callback could be attache to an event that fires less frequently or if the
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* function can be written in such a way that it is only invoked under specific
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* conditions.
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*
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* @param {Function} callback
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* The function to be invoked.
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*
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* @param {Number} wait
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* The time period within which the callback function should only be
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* invoked once. For example if the wait period is 250ms, then the callback
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* will only be called at most 4 times per second.
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*/
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Drupal.debounce = function (callback, wait) {
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"use strict";
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var timeout, result;
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return function () {
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var context = this;
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var args = arguments;
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var later = function () {
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timeout = null;
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result = callback.apply(context, args);
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};
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window.clearTimeout(timeout);
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timeout = window.setTimeout(later, wait);
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return result;
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};
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};
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