55 lines
No EOL
1.4 KiB
JavaScript
55 lines
No EOL
1.4 KiB
JavaScript
var spy = function () {
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var elems = $(":header");
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if (elems.length == 0) {
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return;
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}
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var currentTop = $(window).scrollTop();
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var currentBottom = $(window).scrollTop() + $(window).height();
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var pageBottom = $('#EOF').offset().top;
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var meetUnread = false
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var currentIndex = -1
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elems.each(function (idx) {
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var elemTop = $(this).offset().top;
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var id = $(this).attr('id');
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var navElem = $('#' + id + '-nav');
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if (currentTop + $(this).height() >= elemTop || currentBottom >= pageBottom) {
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navElem.addClass('toc-active');
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} else {
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if (meetUnread == false) {
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meetUnread = true
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currentIndex = idx - 1
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}
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navElem.removeClass('toc-active');
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}
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})
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}
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$().ready(function () {
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$(".collapse").each(function (idx) {
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$(this).collapse("show");
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});
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spy();
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$(window).bind('scroll', throttle(spy));
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});
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function throttle(func, timeout = 250) {
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let last;
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let timer;
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return function () {
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const context = this;
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const args = arguments;
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const now = +new Date();
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if (last && now < last + timeout) {
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clearTimeout(timer)
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timer = setTimeout(function () {
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last = now
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func.apply(context, args)
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}, timeout)
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} else {
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last = now
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func.apply(context, args)
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}
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}
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} |