jQuery – 如何只在视图中加载我的计数器？

我非常擅长修补jQuery。 我找到了一个计数器计数器的解决方案，用于显示％的节省。

我遇到的问题是，它在页面加载后立即运行，并且元素在屏幕下方稍微移动，并且它失去了效果，因为当访问者看到站点时，计数器已经到达数字。

我需要等待加载，直到它在浏览器中进入视图。 我感谢任何帮助。 谢谢。

(function ($) { $.fn.countTo = function (options) { options = options || {}; return $(this).each(function () { // set options for current element var settings = $.extend({}, $.fn.countTo.defaults, { from: $(this).data('from'), to: $(this).data('to'), speed: $(this).data('speed'), refreshInterval: $(this).data('refresh-interval'), decimals: $(this).data('decimals') }, options); // how many times to update the value, and how much to increment the value on each update var loops = Math.ceil(settings.speed / settings.refreshInterval), increment = (settings.to - settings.from) / loops; // references & variables that will change with each update var self = this, $self = $(this), loopCount = 0, value = settings.from, data = $self.data('countTo') || {}; $self.data('countTo', data); // if an existing interval can be found, clear it first if (data.interval) { clearInterval(data.interval); } data.interval = setInterval(updateTimer, settings.refreshInterval); // initialize the element with the starting value render(value); function updateTimer() { value += increment; loopCount++; render(value); if (typeof(settings.onUpdate) == 'function') { settings.onUpdate.call(self, value); } if (loopCount >= loops) { // remove the interval $self.removeData('countTo'); clearInterval(data.interval); value = settings.to; if (typeof(settings.onComplete) == 'function') { settings.onComplete.call(self, value); } } } function render(value) { var formattedValue = settings.formatter.call(self, value, settings); $self.text(formattedValue); } }); }; $.fn.countTo.defaults = { from: 0, // the number the element should start at to: 0, // the number the element should end at speed: 5000, // how long it should take to count between the target numbers refreshInterval: 1000, // how often the element should be updated decimals: 0, // the number of decimal places to show formatter: formatter, // handler for formatting the value before rendering onUpdate: null, // callback method for every time the element is updated onComplete: null // callback method for when the element finishes updating }; function formatter(value, settings) { return value.toFixed(settings.decimals); } }(jQuery)); 

 
 
    %   
  
less than the "other guys"
 
 
    $(document).ready(function(){ $('.number-count').countTo(); });  

所有的CSS渲染并正常运行..如果我需要在这里添加它，请告诉我，我会很乐意这样做。

Answer 1

您可以使用scroll事件操作脚本。

 function isScrolledIntoView(elem) { var $elem = $(elem); var $window = $(window); var docViewTop = $window.scrollTop(); var docViewBottom = docViewTop + $window.height(); var elemTop = $elem.offset().top; var elemBottom = elemTop + $elem.height(); return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop)); } var message = $('#message'); $(window).scroll(function() { if (isScrolledIntoView('#hiddenElem')) { message.text("Visible"); } else { message.text("Invisible"); } }); 

  
 
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