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/** |
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* Keeps WordPress core's admin-menu pinning in sync with the real page height. |
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* |
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* Core measures #wpwrap once and reuses that figure to decide whether to pin |
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* the admin menu. Plugin pages change height after that measurement — tab |
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* panels being shown or hidden, list tables loading over AJAX, sections |
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* expanding — and core is never told. It then works from a stale height, |
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* concludes the page is too short to pin, and lets the menu scroll off-screen |
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* on a page that is in fact tall enough. |
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* |
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* Watching the document for height changes and re-firing the event core |
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* already listens for keeps the two in agreement, without having to patch |
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* every feature that changes layout. |
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* |
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* @package Metasync |
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*/ |
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(function ($) { |
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'use strict'; |
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|
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if (typeof window.ResizeObserver === 'undefined') { |
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return; |
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} |
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|
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$(function () { |
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var lastHeight = document.documentElement.scrollHeight; |
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var pending = null; |
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|
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function notifyCore() { |
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var height = document.documentElement.scrollHeight; |
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|
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// Ignore sub-pixel churn so the observer cannot feed itself. |
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if (Math.abs(height - lastHeight) < 2) { |
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return; |
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} |
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|
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lastHeight = height; |
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$(document).trigger('wp-window-resized'); |
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} |
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|
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function schedule() { |
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window.clearTimeout(pending); |
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pending = window.setTimeout(notifyCore, 100); |
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} |
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|
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new window.ResizeObserver(schedule).observe(document.body); |
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|
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// Late-loading fonts, images and iframes shift the page after ready. |
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$(window).on('load', schedule); |
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}); |
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})(jQuery); |
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|
