更改滚动上的div高度

本文介绍了更改滚动上的div高度的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我想要的是在顶部(标头)的div，它在您首次加载页面时处于最大高度(50px)，并且当您向下滚动页面时，我希望高度平滑地减小到最小高度为30px.我猜我应该为此使用jQuery，但是我没有那么丰富的经验，所以我目前不知道解决方案.

What I want is a div at the top (header) that will be at maximum height (50px) when you first load the page, and when you're scrolling down the page I want the height to smoothly decrease to a minimun height of 30px. I'm guessing I should use jQuery for this but I'm not that experienced so I don't know a solution at the moment.

这是我当前未开发的HTML和CSS:

Here's my current, undeveloped HTML and CSS:

[HTML]

<html>
    <head>
        <link rel="stylesheet" type="text/css" href="css/main.css">
    </head>

    <body>
        <!-- Header -->
        <div id="header_parent">

        </div>

        <!-- Body (homepage) -->
        <div id="body_parent">

        </div>

        <!-- Footer -->
        <div id="footer_parent">

        </div>

    </body>
</html>

[CSS]

* {
    margin:0 auto;
    padding:0;
}

#header_parent {
    max-width:1250px;
    min-width:750px;
    height:50px;
}

很明显，我要说的是#header_parent元素.

So to be clear, the #header_parent element is what I'm talking about.

我还找到了一个他们解决此问题的网站: tvgids.tv (不要看内容，这是我在说的它们的上方灰色标头.我尝试看了一下源代码，但这并没有给我带来更多的知识.)

I also found a website on which they achieved this matter: tvgids.tv(don't look at the content, it's they upper grey header I'm talking about. I tried looking at the source code but that didn't give me any more knowledge.)

推荐答案

我已添加到#body_parent高度以查看滚动条，创建站点后可以删除具有高度的行.

I've added to #body_parent height to see the scroll, you can delete that row with height after you create the site.

这是jsfiddle

Here is jsfiddle

$(window).on('scroll', function () {
    var scrollTop = $(window).scrollTop();
    if (scrollTop > 50) {
        $('#header_parent').stop().animate({height: "30px"},200);
    }
    else {
         $('#header_parent').stop().animate({height: "50px"},200);
    }
});

* {
    margin:0 auto;
    padding:0;
}

#header_parent {
    max-width:1250px;
    min-width:750px;
    height:50px;
    background:#000;
    position:fixed;
}

#body_parent {
     height:1200px;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<body>
    <!-- Header -->
    <div id="header_parent">

    </div>

    <!-- Body (homepage) -->
    <div id="body_parent">

    </div>

    <!-- Footer -->
    <div id="footer_parent">

    </div>

</body>

或HTML

<html>
    <head>
        <link rel="stylesheet" type="text/css" href="css/main.css">
    </head>

    <body>
        <!-- Header -->
        <div id="header_parent">

        </div>

        <!-- Body (homepage) -->
        <div id="body_parent">

        </div>

        <!-- Footer -->
        <div id="footer_parent">

        </div>

     <!-- jQuery library -->
     <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
     <!-- Your jQuery/Javascript code -->
     <script  type="text/javascript">
     $(window).on('scroll', function () {
        var scrollTop = $(window).scrollTop();
        if (scrollTop > 50) {
            $('#header_parent').stop().animate({height: "30px"},200);
        }
        else {
             $('#header_parent').stop().animate({height: "50px"},200);
        }
     });
     </script>
    </body>
</html>

如果要设置平滑度，请用数字替换200，以毫秒为单位的平均持续时间为200.

And if you want to set smoothness replace 200 with your number, 200 mean duration in miliseconds.

$('#header_parent').stop().animate({height: "50px"},200);

这篇关于更改滚动上的div高度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！