demo/3_0_fade.html

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
        <meta name="renderer" content="webkit">
        <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
        <title>Fade</title>
        <link rel="stylesheet" href="../dist/do-slide.min.css">
        <link rel="stylesheet" href="css/common.css">
        <style>
            div.container > * {
                position: absolute;
                -webkit-transition: opacity 1s;
                transition: opacity 1s;
                opacity: 0;
            }
        </style>
    </head>
    <body>
        <div class="wrap ds-parent">
            <div class="ds-container container">
                <div class="section">
                    <span class="arrow down"></span>
                </div>
                <div class="section">
                    <span class="arrow down"></span>
                    <span class="arrow up"></span>
                </div>
                <div class="section">
                    <span class="arrow down"></span>
                    <span class="arrow up"></span>
                </div>
                <div class="section">
                    <span class="arrow up"></span>
                </div>
            </div>
        </div>
        <script type="text/javascript" src="../dist/do-slide.min.js"></script>
        <script type="text/javascript">

            var slide = new DoSlide('.container', {
                silent: true,
                duration: 1000
            })

            slide.onBeforeChange(function(curIndex, tarIndex, cur, tar) {
                this.$(cur).css('opacity', '0')
                this.$(tar).css('opacity', '1')
            }).do(function(curIndex, cur) {
                this.$(cur).css('opacity', '1')  // init
            })

        </script>
    </body>
</html>