html - 导航栏在固定时跟随滚动

Question

我在网站上有一个产品页面。我有一个像家一样的顶级菜单，关于等等....然后我试图在左侧有一个与产品列表保持固定的菜单。看图:

使用我当前的代码，但是左侧的菜单跟随滚动，这里是代码:

<div id="product-list">
<ul>
  <li><a href="bfm.html">item 1</a></li>
  <li><a href="hbm.html">item 1</a></li>
  <li><a href="laminated.html">item 1</a></li>
  <li><a href="ps.html">item 1</a></li>
  <li><a href="pm.html">item 1</a></li>
  <li><a href="wm.html">item 1</a></li>
</ul>
</div>

#product-list{
    position:fixed;
}
#product-list ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    width: 12%;
    background-color: #FFF;
    position:fixed;
    height: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    padding-top:10%;
}
#product-list li{
    overflow: hidden;
    text-overflow: ellipsis;
}
#product-list li a {
    display: block;
    color: #000;
    padding: 8px 0 8px 16px;
    text-decoration: none;
}
#product-list li a:hover:not(.active) {
    background-color: #555;
    color: white;
}

Answer 1

Plunkr Example

我所做的改变

我对您的代码做了几件事。

1. 在您的样式定义中，我删除了一些重复的代码。 #product-list 有几个位置，这使它成为一个固定元素，这很烦人。
2. 我添加了一个“特殊情况”类 #product-list.fixed，它删除了列表顶部的填充并将其 position 更改为 固定，顶部偏移量为0。
3. 我稍微更改了您的 HTML。我删除了产品列表 ul 的包装器 div 并将 #product-list id 添加到 ul .
4. 我还添加了一些 javacript，以便在滚动大于元素的原始位置时向 #product-list 元素添加/删除 .fixed 类。
5. 我添加了一个 transition:all linear 0.3 元素来平滑我们添加 fixed 类时的变化
6. 在下面的代码中，我只是将弹出的图像更改为 placehold.it 图像，这样我就不会占用您的带宽。
7. 编辑更改了 z-index 以允许侧边菜单滑入页脚下方。

代码

下面代码的顺序是

1. Javascript(我用的是jQuery，超流行的框架)
2. CSS(您可能想研究像 Bootstrap 这样的 CSS 框架，它可以减少您的开发时间)
3. HTML

$(document).ready(function() {
  var side_offset = $('#product-list').offset();
  //Initial offset.
  $(document).on('scroll', function() {
    $('#product-list').toggleClass('fixed', $(document).scrollTop() > side_offset.top);
  });
})

@charset "utf-8";

/* CSS Document */

html * {
  font-family: verdana;
  !important;
}
#header {
  background-color: #565656;
  color: white;
  text-align: center;
  height: 10%;
  position: relative;
  z-index: 999;
}
#header ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  text-align: center;
  vertical-align: middle;
}
#header li {
  display: inline;
}
#header li a {
  display: inline-block;
  color: white;
  text-align: center;
  padding: 14px 30px;
  text-decoration: none;
  vertical-align: middle;
}
#header li a.active {
  text-decoration: underline;
}
#header li a:hover {
  background-color: #111;
}
#header li a.a-no-hover:hover {
  background-color: transparent;
}
#product-list {
  list-style-type: none;
  margin: 0;
  padding: 0;
  width: 12%;
  background-color: #FFF;
  position: absolute;
  height: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  padding-top: 10%;
  z-index: 100;
  transition: all linear 0.3s;
}
#product-list.fixed {
  position: fixed !important;
  padding-top: 0;
  top: 0;
}
#product-list li {
  overflow: hidden;
  text-overflow: ellipsis;
}
#product-list li a {
  display: block;
  color: #000;
  padding: 8px 0 8px 16px;
  text-decoration: none;
}
#product-list li a:hover:not(.active) {
  background-color: #555;
  color: white;
}
#nav {
  line-height: 30px;
  background-color: #eeeeee;
  height: 300px;
  width: 100px;
  float: left;
  padding: 5px;
}
#section1 {
  width: 90%;
  height: auto;
  overflow: hidden;
  margin: 0 auto;
  text-align: center;
}
#section1 img {
  width: 100%;
  height: auto;
  opacity: 1;
  transition: opacity 0.5s linear;
}
#section3 {
  width: 90%;
  margin: 0 auto;
  text-align: center;
  /*float:left;
    padding:10px;*/
  margin-bottom: 2%;
}
#section2 {
  width: 50%;
  height: auto;
  margin-top: 5%;
  margin-bottom: 5%;
  margin-left: auto;
  margin-right: auto;
  text-align: left;
  /*float:left;*/
  text-align: justify;
  text-justify: inter-word;
}
.centerer {
  text-align: center;
}
#section5 {
  width: 90%;
  height: auto;
  margin-top: 5%;
  margin-bottom: 5%;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
  vertical-align: middle;
  margin-left: 10%;
}
img {
  max-width: 100%;
  max-height: 100%;
}
.container {
  width: 70%;
  margin: 10px auto;
  position: relative;
  text-align: center;
}
.block {
  height: auto;
  width: auto;
  display: inline-block;
  margin: 2%;
  vertical-align: middle;
  padding-left: 2%;
  padding-right: 2%;
  font-size: 1.2em;
}
.floating-product {
  display: inline-block;
  width: 20%;
  height: 20%;
  /*border: 3px solid #565656;*/
  padding: 1%;
  margin: 0 auto;
  margin-top: 2%;
  margin-bottom: 2%;
  text-align: center;
  vertical-align: middle;
}
.floating-product img {
  margin: 0 auto;
  max-width: 100%;
  max-height: 100%;
  display: block;
}
.floating-product a {
  color: #000;
}
.floating-product a:hover {
  color: #565656;
}
.block a {
  color: #000;
}
.block a:hover {
  color: #565656;
}
#footer {
  background-color: #565656;
  color: white;
  overflow: auto;
  /*clear: both;*/
  text-align: left;
  padding: 1% 5%;
  height: 10%;
  vertical-align: middle;
  position: relative;
  z-index: 999;
}
hr {
  width: 70%;
}
h1 {
  text-align: left;
  font-size: 1.5em;
  margin-left: 11%;
}
.margin {
  margin-left: 11%;
}
span {
  background: transparent;
}
table {
  margin-top: 5%;
}
.tg {
  border-collapse: collapse;
  border-spacing: 0;
  width: 99%;
  margin: 0 auto;
  font-size: 1.1em;
  font-weight: 100;
}
.tg td {
  padding: 5px 10px;
  border-style: none;
  border-width: 1px;
  overflow: hidden;
  word-break: normal;
  font-weight: 100;
}
.tg th {
  font-weight: 100;
  padding: 5px 10px;
  border-style: none;
  border-width: 1px;
  overflow: hidden;
  word-break: normal;
}
.tg .tg-lqy6 {
  text-align: right;
  vertical-align: top;
  padding-right: 3%;
}
.tg .tg-yw4l {
  vertical-align: top;
  text-align: left;
  padding-left: 3%;
}
a.fancybox img {
  border: none;
  box-shadow: 0 1px 7px rgba(0, 0, 0, 0.6);
  -o-transform: scale(1, 1);
  -ms-transform: scale(1, 1);
  -moz-transform: scale(1, 1);
  -webkit-transform: scale(1, 1);
  transform: scale(1, 1);
  -o-transition: all 0.2s ease-in-out;
  -ms-transition: all 0.2s ease-in-out;
  -moz-transition: all 0.2s ease-in-out;
  -webkit-transition: all 0.2s ease-in-out;
  transition: all 0.2s ease-in-out;
}
a.fancybox:hover img {
  position: relative;
  z-index: 999;
  -o-transform: scale(1.03, 1.03);
  -ms-transform: scale(1.03, 1.03);
  -moz-transform: scale(1.03, 1.03);
  -webkit-transform: scale(1.03, 1.03);
  transform: scale(1.03, 1.03);
}
.imager {
  display: inline-block;
  width: 15%;
  height: 10%;
  padding: 1%;
  margin: 0 auto;
  margin-top: 2%;
  margin-bottom: 2%;
  text-align: center;
  vertical-align: middle;
}
.imager img {
  margin: 0 auto;
  max-width: 100%;
  max-height: 100%;
  display: block;
}
.black a {
  float: right;
  color: #000
}
.black a:hover {
  color: #565656;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="header">
  <ul>
    <li>
      <a class="a-no-hover" href="index.html">
        <img src="placehold.it/300x300" />
      </a>
    </li>
    <li>
      <a href="index.html">HOME</a>
    </li>
    <li>
      <a class="active" href="product.html">PRODUCTS</a>
    </li>
    <li>
      <a href="order.php">ORDER</a>
    </li>
    <li>
      <a href="about.html">ABOUT US</a>
    </li>
    <li>
      <a href="contact.html">CONTACT US</a>
    </li>
  </ul>
</div>
<ul id="product-list">
  <li>
    <a href="bfm.html">Composite Bag Filter Media</a>
  </li>
  <li>
    <a href="hbm.html">High Dust-Loading Bag Filter Media</a>
  </li>
  <li>
    <a href="laminated.html">Laminated Composite Filter Media</a>
  </li>
  <li>
    <a href="ps.html">Polyester Synthetic Fibre Filter Media</a>
  </li>
  <li>
    <a href="pm.html">Polypropylene Melt-Blown Filter Media</a>
  </li>
  <li>
    <a href="wm.html">Wire Mesh Backed Composite Filter Media</a>
  </li>
</ul>
<div id="section5">
  <h1>Product Listing</h1>
  <div class="floating-product">
    <a href="bfm.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>Composite Bag Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="bfm.html">Read more...</a>
    </p>
  </div>
  <div class="floating-product">
    <a href="hbm.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>High Dust-Loading Bag Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="hbm.html">Read more...</a>
    </p>
  </div>
  <div class="floating-product">
    <a href="laminated.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>Laminated Composite Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="laminated.html">Read more...</a>
    </p>
  </div>
  <div class="floating-product">
    <a href="ps.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>Polyester Synthetic Fibre Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="ps.html">Read more...</a>
    </p>
  </div>
  <div class="floating-product">
    <a href="pm.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>Polypropylene Melt-Blown Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="pm.html">Read more...</a>
    </p>
  </div>
  <div class="floating-product">
    <a href="wm.html">
      <img class="displayed" src="//placehold.it/300x300" />
      <br />
      <h4>Wire Mesh Backed Composite Filter Media</h4>
    </a>
    <p>
      <a style="color:#06F" href="wm.html">Read more...</a>
    </p>
  </div>
</div>
<div id="footer">
  <span style="float:left;">
        <b>Contact Us</b>
        <br />

  Email: contact@dongguanhy.com        <br />

  Contact Phone: +86-769-23150100        <br />

  Contact Fax: +86-769-23152700        <br />

  Company Address: Liu Yong Wei Industry Area, DongGuan, GuandDong Province, China        <br />
      </span>
  <span style="float:right;">
        <b>Follow Us</b>
        <br />
        <br />
        <a href="http://facebook.com/dongguanhy/" target="_blank">
          <img src="placehold.it/300x300" />
        </a>
        <!--<img src="http://mmo-stream.net/dong/images/linkedin.png"/>-->
      </span>
</div>