JS-缓冲运动-对联型悬浮框 

<!DOCTYPE html>
<html>

    <head>
        <meta charset="UTF-8">
        <title>缓冲运动2</title>
        <style type="text/css">
        body{
            height: 2000px;
        }
            .div {
                width: 100px;
                height: 100px;
                background-color: darkslateblue;
                position: absolute;
                right: 0;
                /*bottom: 0;*/
                cursor: pointer;
            }
        </style>
        <script type="text/javascript">
        window.onscroll= function(){
            //1,给浏览器的滚动添加事件，onscollTop事件
            var oDiv = document.getElementById('div');
            var scrollTop = document.documentElement.scrollTop||document.body.scrollTop;
//            oDiv.style.top = (document.documentElement.clientHeight-oDiv.offsetHeight)/2+scrollTop+'px';
            //可视区域的高度减掉物体高度再加上向上滚动的高度
            starMove(parseInt((document.documentElement.clientHeight-oDiv.offsetHeight)/2+scrollTop));
            //除以2以后就一直抖,就用parseInt取整
        };
        var timer = null;
        function starMove(iTarget){
            var oDiv = document.getElementById('div');
            clearInterval(timer);
            timer = setInterval(function(){
                var speed = (iTarget-oDiv.offsetTop)/4;
                speed=speed>0?Math.ceil(speed):Math.floor(speed);
                if(oDiv.offsetTop==iTarget){
                    clearInterval(timer)
                }else{
                    document.title = iTarget;
                    document.getElementById('btn').value=oDiv.offsetTop;
                    oDiv.style.top = oDiv.offsetTop+speed+'px';
                }
            },30)
        }
        
        </script>
    </head>

    <body>
        <div class="div" id="div"></div>
    <input type="text" value="" id="btn" style="top: 0;
        right: 0;
        position: fixed;"/>
    </body>

</html>

课程链接：智能社的开发教程：https://ke.qq.com/webcourse/index.html#course_id=152997&term_id=100174752&taid=766913655494053&vid=v14127nxshc

posted @ 2017-02-15 21:27  xing.org1^  阅读(223)  评论(0)  编辑  收藏  举报