虽然目前这在纯 CSS 中是不可能的,但通过使用window.onscroll
、scrollTop
和几个if
语句,您可以创建一个可爱的状态更改效果,类似于您正在寻找的效果
查看 Google Plus 页面,导航上方有一些内容。结果,我将我的 HTML 设置如下
<div class='topContent'>Top Content</div>
<nav>
<div class='googleSlide'></div> <!--The image that slides in from the left-->
<div class='navContent'>Nav bar content</div> <!-- Everything else in nav -->
</nav>
这是我重要的 CSS 行,以使其正常运行
.topContent { height:75px; /* Arbitrary but necessary value */ }
nav { height:44px; width:100%; }
nav div { float:left; }
.googleSlide {
background-image: url(//ssl.gstatic.com/s2/oz/images/sprites/ribbon-nav-1x-69dd561f4c55d6702aadda4e3b4ce787.png);
background-position:0 -100px;
height: 44px; /* More arbitrary but necessary values */
width: 44px;
margin-left:-55px;
transition: all 0.200s; /* To smooth the transition to the new state */
}
最后,我们有了让这一切正常工作的 javascript
window.onscroll = function() { // Fires whiles the page scrolls
var navigation = document.getElementsByTagName('nav')[0],
slide = document.getElementsByClassName('googleSlide')[0];
// Conditional to check whether scroll is past our marker, second conditional
// to make sure that it doesn't keep firing when scrolling inside of the range
if(document.body.scrollTop > 75 && navigation.style.background != 'white') {
navigation.style.background = 'white';
navigation.style.border = '1px solid black';
navigation.style.position = 'fixed';
slide.style.marginLeft = '0px';
}
// Same as above but toggles back to the original state
if(document.body.scrollTop < 75 && navigation.style.background != 'grey') {
navigation.style.background = 'grey';
navigation.style.border = 'none';
slide.style.marginLeft = '-55px';
navigation.style.position = 'static';
navigation.style.top = '0px';
}
}
演示
我不确定滚动背景的确切含义,但是与此类似的方法可以为您提供所需的