LazyLaoding CSS背景(不是HTML< img>标签) [英] LazyLaoding CSS background (not HTML <img> tags)
问题描述
我设法弄清楚了如何在我的网站上延迟加载图片，并通过< img> 标签将图片调用为HTML.我在GitHub上使用了此软件包来完成此操作.但是我在完成时遇到了麻烦与CSS background:的情况相同.
I've managed to figure out how to lazyload images on my website where the images are called into the HTML via <img> tags. I used this package on GitHub to accomplish this. However I'm having trouble acomplishing the same thing with CSS background:'s.
-有关此问题的一些信息:
我昨晚创建了一个图像菜单栏，该菜单栏根据浏览器屏幕(提供链接)来更改图像大小/位置.此图像菜单栏中的所有图像都是通过CSS中的 background:调用的(而不是通过< img> 标记).
I created an image menu bar last night that changes image size/position based on the browsers screen (Link provided). All the images in this image menu bar are called in via background: within the CSS (not through an <img> tag).
-现在是我的问题:
我如何在此我已经开始的项目.在我的网站上，按照以下说明进行操作后，我只需将< img src ="> 更改为< img data-src =" (在HTML中)点击上方的Github链接，图像将在屏幕上显示时加载.
How am i able to lazyload the background: images within the css of this project I've started. On my website I would just change <img src=""> to <img data-src="" (within the HTML) after following the instructions from the Github link above, and images will load as they become visible on the screen.
-执行此操作的原因:
这纯粹是为了加快网站速度，并避免一次加载所有图像.确保该加载时间不会浪费任何其他提示，或者解决此问题的任何其他可能方式，将不胜感激.
This is purely to speed up the website and to avoid loading all images at once. Any other tips to ensure this does not take a toll on loading time, or any other possible ways around this issue would be appreciated.
-注意:对于该项目，我使用了 background:而不是 background-image:.
-Note: I've used background: and not background-image: for this project.
如果您错过了我项目的链接: https://jsfiddle.net/Shololom/wbgn210y/
推荐答案
来自 Github您提供的项目:
何时使用:您的图像被设置为CSS背景图像，而不是真实的img，但是您仍然希望延迟加载它们.
When to use: your images are set as CSS background images instead of real img, but you still want to lazily load them.
<div class="lazy" data-src="../img/44721746JJ_15_a.jpg"></div>
Javascript
var myLazyLoad = new LazyLoad({
elements_selector: ".lazy"
});
就是这样.每当由elements_selector选择的元素不是img或iframe时，LazyLoad会将在data-src属性中找到的图像放在该元素的背景图像中.
That's it. Whenever the element selected by elements_selector is not an img or an iframe, LazyLoad puts the image found in the data-src attribute in the background-image of the element.
// Get products
var product1 = document.getElementById('product1');
var product2 = document.getElementById('product2');
var product3 = document.getElementById('product3');
var product4 = document.getElementById('product4');
var product5 = document.getElementById('product5');
// Create Lazy loader
var myLazyLoad = new LazyLoad({
elements_selector: ".lazy"
});
// Load images in a responsive way
function loadImgs() {
console.log('Loading images ...');
var src1;
var src2;
var src3;
var src4;
var src5;
if(window.matchMedia("only screen and (max-width:700px)").matches) {
/* The viewport is lesser than 700 pixels wide */
src1 = product1.getAttribute('data-src-small');
src2 = product2.getAttribute('data-src-small');
src3 = product3.getAttribute('data-src-small');
src4 = product4.getAttribute('data-src-small');
src5 = product5.getAttribute('data-src-small');
} else {
src1 = product1.getAttribute('data-src-large');
src2 = product2.getAttribute('data-src-large');
src3 = product3.getAttribute('data-src-large');
src4 = product4.getAttribute('data-src-large');
src5 = product5.getAttribute('data-src-large');
}
// Set the data-src for lazy loader
product1.setAttribute('data-src', src1);
product2.setAttribute('data-src', src2);
product3.setAttribute('data-src', src3);
product4.setAttribute('data-src', src4);
product5.setAttribute('data-src', src5);
// Tell lazy loader that the data should be re-processed
product1.removeAttribute('data-was-processed');
product2.removeAttribute('data-was-processed');
product3.removeAttribute('data-was-processed');
product4.removeAttribute('data-was-processed');
product5.removeAttribute('data-was-processed');
// Tell lazy loader to update
myLazyLoad.update();
}
// Load images first time
loadImgs();
// Reload images when window is resized
var lastWindowSize = window.innerWidth;
window.onresize = function(event) {
var currentWindowSize = window.innerWidth;
if((lastWindowSize <= 700 && currentWindowSize > 700) || (lastWindowSize > 700 && currentWindowSize <= 700)) {
loadImgs();
}
lastWindowSize = currentWindowSize;
};.top-header-settings {
font-family: inherit;
font-size: 18px;
font-weight: 400;
text-transform: uppercase;
letter-spacing: .1em;
margin: 0 0 45px;
padding: 45px 0 0;
color: #524949;
border-top: 1px solid #ddd;
}
.top-menu-wrap {
margin: 0 auto;
position: relative;
;
background-color: #343434;
}
.top-menu-inner {
max-width: 1200px;
height: 260px;
/*/background-color:#343434;/*/
margin: 0 auto;
}
.top-menu-innerr {
max-width: 1161px;
height: 200px;
margin: 0 auto;
padding-top: 20px;
}
.top-menu-button {
width: 220px;
height: 220px;
display: inline-block;
margin: 5px;
text-align: center;
font-size: 16px;
opacity: .6;
transition: 0.3s;
}
.top-menu-button:hover {
opacity: 1
}
@font-face {
font-family: 'roboto';
src: url(https://fonts.googleapis.com/css?family=Roboto);
}
.top-menu-text {
width: 125px;
height: 30px;
/*/background-color:red;/*/
margin: 150px auto;
text-align: center;
color: white;
font-family: 'roboto';
font-size: 20px;
background: #343434;
-khtml-opacity: .50;
-moz-opacity: .50;
-ms-filter: "alpha(opacity=50)";
filter: alpha(opacity=50);
filter: progid:DXImageTransform.Microsoft.Alpha(opacity=0.5);
opacity: .60;
border-style: solid;
border-width: 1px;
line-height: 25px;
}
.coming-soon-top {
width: 75px;
height: 20px;
font-size: 10px;
text-align: center;
color: white;
position: absolute;
font-family: 'roboto';
background: #c78f8f;
}
@media only screen and (max-width:1200px) {
.top-menu-wrap {
margin: 0 auto;
position: relative;
background-color: #343434;
}
.top-menu-inner {
max-width: 1200px;
min-height: 340px;
/*/ background-color:#343434;/*/
margin: 0 auto;
}
.top-menu-innerr {
max-width: 80%;
min-height: 200px;
width: 80vw;
margin: 0 auto;
/*/background:red;/*/
}
.top-menu-button {
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
float: left;
margin: 1px auto;
text-align: center;
font-size: 16px;
margin: 4px 2px;
opacity: 1;
transition: 0.3s;
color: white;
}
.top-menu-button:hover {
opacity: .6
}
#product2 {
/*background: url("http://via.placeholder.com/1080x1080");*/
/*/background:#c77f7f;/*/
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
}
#product1 {
/*background: url("http://via.placeholder.com/1080x1080");*/
/*/background:#c77f7f;/*/
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
}
#product3 {
/*background: url("http://via.placeholder.com/1080x1080");*/
/*/background:#c77f7f;/*/
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
}
#product4 {
/*background: url("http://via.placeholder.com/1080x1080");*/
/*/background:#c77f7f;/*/
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
}
#product5 {
/*background: url("http://via.placeholder.com/1080x1080");*/
/*/background:#c77f7f;/*/
width: 80vw;
height: 80vw;
max-width: 1080px;
max-height: 1080px;
background-repeat: no-repeat;
background-size: contain;
background-position: center;
}
.top-menu-text {
/*/width:125px;/*/
/*/height:30px;/*/
width: 30vw;
height: 10vw;
/*/background-color:red;/*/
margin: 150px auto;
text-align: center;
color: white;
font-size: 5.9vw;
line-height: 9vw;
}
}<script src="https://cdnjs.cloudflare.com/ajax/libs/vanilla-lazyload/8.7.1/lazyload.min.js"></script>
<div class="top-menu-warp">
<div class="top-menu-inner">
<div class="top-menu-innerr">
<a href="#">
<div id="product1" class="top-menu-button lazy"
data-src-small="http://via.placeholder.com/220x220"
data-src-large="http://via.placeholder.com/1080x1080">
<div class="coming-soon-top">
Most Popular
</div>
<div class="top-menu-text">
Text
</div>
</div>
</a>
<a href="#">
<div id="product2" class="top-menu-button lazy"
data-src-small="http://via.placeholder.com/220x220"
data-src-large="http://via.placeholder.com/1080x1080">
<div class="top-menu-text">
Text
</div>
</div>
</a>
<a href="#">
<div id="product3" class="top-menu-button lazy"
data-src-small="http://via.placeholder.com/220x220"
data-src-large="http://via.placeholder.com/1080x1080">
<div class="top-menu-text">
Text
</div>
</div>
</a>
<a href="#">
<div id="product4" class="top-menu-button lazy"
data-src-small="http://via.placeholder.com/220x220"
data-src-large="http://via.placeholder.com/1080x1080">
<div class="top-menu-text">
Text
</div>
</div>
</a>
<a href="#">
<div id="product5" class="top-menu-button lazy"
data-src-small="http://via.placeholder.com/220x220"
data-src-large="http://via.placeholder.com/1080x1080">
<div class="coming-soon-top">
Coming soon
</div>
<div class="top-menu-text">
Text
</div>
</div>
</a>
</div>
</div>这篇关于LazyLaoding CSS背景(不是HTML< img>标签)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
