示例： http: //www.chartjs.org/
向下滚动时，每篇文章都会在它进入浏览器的视口时显示。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？我怎样才能实现这种滚动->淡入效果？
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);
}
});
});
穆罕默德的回答没有考虑任何绝对定位的图像......我们应该使用偏移量而不是位置
$(window).scroll(function () {
/* Check the location of each desired element */
$('.article').each(function (i) {
var bottom_of_object = $(this).offset().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);
}
});
});
因为我在评论中读到：
如果您希望对象在对象的1/3可见时淡入，请使用以下代码：
jQuery：
$(document).ready(function() {
/* Every time the window is scrolled ... */
$(window).scroll( function(){
/* Check the location of each desired element */
$('.hideme').each( function(i){
var bottom_of_object = $(this).position().top + ($(this).outerHeight())/3;
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);
}
});
});
});
我改变的唯一行是：
var bottom_of_object = $(this).position().top + ($(this).outerHeight())/3;
通过更改/3为例如/4，您可以让它淡入，当对象的 1/4 可见时。
最佳工艺：
HTML：
<div id="container">
<div id="monster">Hello</div>
<div>Hello</div>
<div class="hideme">Fade In</div>
<div class="hideme">Fade In</div>
<div class="hideme">Fade In</div>
<div class="hideme">Fade In</div>
<div class="hideme">Fade In</div>
</div>
jQuery：
$(function(){ // $(document).ready shorthand
$('.monster').fadeIn('slow');
});
$(document).ready(function() {
/* Every time the window is scrolled ... */
$(window).scroll( function(){
/* Check the location of each desired element */
$('.hideme').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'},1500);
}
});
});
});
CSS：
#container
{
height:2000px;
}
#container DIV
{
margin:50px;
padding:50px;
background-color:pink;
}
.hideme
{
opacity:0;
}