我实现了我在网上找到的这段代码,并添加了一个if语句,用于检查元素之前是否已经过动画。如果有,它应该删除使其成为动画目标的类。出于某种原因,它不起作用,并且元素每当它进入视口时都会生成动画,而不仅仅是第一次像我希望的那样。jQuery - 在滚动bug上动画
var $flyInLeft = $('.fly-in-left');
var $window = $(window);
function check_if_in_view() {
var window_height = $window.height();
var window_top_position = $window.scrollTop();
var window_bottom_position = (window_top_position + window_height);
$.each($flyInLeft, function() {
var $element = $(this);
var element_height = $element.outerHeight();
var element_top_position = $element.offset().top;
var element_bottom_position = (element_top_position + element_height);
//check to see if this current container is within viewport
if ((element_bottom_position >= window_top_position) &&
(element_top_position <= window_bottom_position)) {
$element.addClass('animated slideInLeft already-viewed');
} else {
$element.removeClass('animated slideInLeft');
}
// This is the bit that doesn't seem to work.
if ($element.hasClass('already-viewed')) {
$element.removeClass('fly-in-left');
}
});