Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
575 views
in Technique[技术] by (71.8m points)

jquery - How to fade loop background images?

Rookie here .. I'm trying to make my static background become a carousel.. my current html looks something like this:

<body>
    <div class="pageContent">
    </div>
</body>

and my CSS:

body {
    background: url('http://placehold.it/1600x1200') no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

So I'd like to make the background now cycle images and stay responsive .. Can this be done easily using CSS3? or should I maybe wrap the contents of my html in a carousel with bootstrap? I wasn't able to find a good example of how to do this. Thanks in advance.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

jsBin demo

Full page gallery fade

I would do it using an absolute positioned DIV overlaying the body. Fade in the DIV with a new image, then set the same image to body and hide the DIV like: (GRAY is BODY, SOrange is DIV)

Responsive background fade gallery logic

The increment of the current image Array is achieved by preincrementing ++counter.

The loop fix is than achieved using Remainder Operator% to prevent the counter from exceeding the number of images in Array.

The loop itself is done inside .fadeTo() callback function by simply do a new iteration of the loopBg() function.

This is the needed CSS:

*{margin:0;padding:0;} /* Global reset */
html, body{height:100%;width:100%;}
body, #bg{ background: #000 none 50% / cover; }
#bg{
  position:absolute;
  top:0;
  bottom:0;
  left:0;
  right:0;
  width:100%;
  height:100%;
}

And the jQ:

var images = [
  "bg0.jpg",
  "bg1.jpg",
  "bg2.jpg"
];
var $body = $("body"),
    $bg = $("#bg"),
    n = images.length,
    c = 0; // Loop Counter

// Preload Array of images...
for(var i=0; i<n; i++){
  var tImg = new Image();
  tImg.src = images[i];
}

$body.css({backgroundImage : "url("+images[c]+")"}); 

(function loopBg(){
  $bg.hide().css({backgroundImage : "url("+images[++c%n]+")"}).delay(2000).fadeTo(1200, 1, function(){
    $body.css({backgroundImage : "url("+images[c%n]+")"}); 
    loopBg();
  });
}());

Edit: If you want to keep the background changing but make the content scrollable, simply add overflow:auto; to #page like in this demo: http://jsbin.com/huzayiruti/1/


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...