jquery - 使用CSS在向下滚动时淡入元素

Question

示例: http://www.chartjs.org/

当向下滚动时，每篇文章都会在进入浏览器视口(viewport)时显示出来。 CSS是

#examples article {
    -webkit-transition: opacity 200ms ease-in-out;
    -ms-transition: opacity 200ms ease-in-out;
    -moz-transition: opacity 200ms ease-in-out;
    -o-transition: opacity 200ms ease-in-out;
    transition: opacity 200ms ease-in-out;
    position: relative;
    margin-top: 20px;
    clear: both;
}

我试过这个 css 但它不起作用。是否有一些与 css 一起工作的 javascript？如何实现这种滚动->淡入效果？

Answer 1

Demo Fiddle

你想要这样的东西吗？

   $(window).scroll(function () {

        /* Check the location of each desired element */
        $('.article').each(function (i) {

            var bottom_of_object = $(this).position().top + $(this).outerHeight();
            var bottom_of_window = $(window).scrollTop() + $(window).height();

            /* If the object is completely visible in the window, fade it it */
            if (bottom_of_window > bottom_of_object) {

                $(this).animate({
                    'opacity': '1'
                }, 500);

            }

        });

    });