如何创建滚动后固定到顶部的粘性导航栏

Question

我试图在首次加载网站时创建一个出现在可查看页面底部的导航栏,然后当用户向下滚动时,导航栏向上滚动,最终固定到顶部.我正在使用Bootstrap,就像这个网站一样,但我无法弄清楚这个网站是如何做到的.有帮助吗？

这是我试图效仿的导航栏的网站:http://www.blastprocessor.co.uk/

这是我的导航html和css代码:

HTML:

<div class="navbar navbar-fixed-top" id="navbar">
    <div class="navbar-inner">
        <div class="container">
            <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            </a>
            <div class="nav-collapse">
                <ul class="nav nav-pills">
                    <li class="active"><a href="#home">Home</a></li>
                    <li><a href="#service-link">Services</a></li>
                    <li><a href="#contact-link">Contact</a></li>
                </ul><!-- /.nav -->
            </div><!--/.nav-collapse -->
        </div><!-- /.container -->
    </div><!-- /.navbar-inner -->
</div><!-- /.navbar -->

这是我的CSS:

.navbar-fixed-top,.navbar-fixed-bottom{position:fixed; -webkit-box-shadow: none; -moz-box-shadow: none; box-shadow: none;}
.navbar .nav > li a{
    color:white; background:rgba(0,0,0,0.2); text-shadow:none; font-size:1.7em; font-family: marvel, serif; padding:.5em 1.3em; margin:1em 2em;
}
.navbar .nav > .active a:hover, .navbar .nav > li a:hover, .navbar .nav > .active a {
    color:white; ; background:#F90; text-shadow:none; font-size:1.7em; font-family: marvel, serif; padding:.5em 1.3em; margin:1em 2em;
}
.navbar .nav > li {padding:2em;}
.navbar.navbar-fixed-top .navbar-inner{background: rgba(255, 255, 255, 0);}
.navbar .nav, .navbar .nav > li {
    float:none;
    display:inline-block;
    *display:inline; /* ie7 fix */
    *zoom:1; /* hasLayout ie7 trigger */
    vertical-align: top;
    padding:0 2em;
}
.navbar-inner {text-align:center;}
.navbar .navbar-inner, .navbar .navbar-inner {border: none; box-shadow: none; filter: none;}

Answer 1

我正在寻找同样的事情.我曾经读过这个在Bootstrap 3.0中可用,但我实际上没有运气实现它.这就是我提出的,它很有效.非常简单的jQuery和Javascript.

这是JSFiddle玩的... http://jsfiddle.net/CriddleCraddle/Wj9dD/

该解决方案与Web和StackOverflow上的其他解决方案非常相似.如果您没有找到这个有用的,请搜索您需要的内容.祝好运!

这是HTML ...

<div id="banner">
  <h2>put what you want here</h2>
  <p>just adjust javascript size to match this window</p>
</div>

  <nav id='nav_bar'>
    <ul class='nav_links'>
      <li><a href="url">Sign In</a></li>
      <li><a href="url">Blog</a></li>
      <li><a href="url">About</a></li>
    </ul>
  </nav>

<div id='body_div'>
  <p style='margin: 0; padding-top: 50px;'>and more stuff to continue scrolling here</p>
</div>

这是CSS ......

html, body {
  height: 4000px;
}

.navbar-fixed {
  top: 0;
  z-index: 100;
  position: fixed;
  width: 100%;
}

#body_div {
  top: 0;
  position: relative;
  height: 200px;
  background-color: green;
}

#banner {
  width: 100%;
  height: 273px;
  background-color: gray;
  overflow: hidden;
}

#nav_bar {
  border: 0;
  background-color: #202020;
  border-radius: 0px;
  margin-bottom: 0;
  height: 30px;
}

//the below css are for the links, not needed for sticky nav
.nav_links {
  margin: 0;
}

.nav_links li {
  display: inline-block;
  margin-top: 4px;
}

.nav_links li a {
  padding: 0 15.5px;
  color: #3498db;
  text-decoration: none;
}

现在,只需添加javacript即可根据滚动位置添加和删除修复类.

$(document).ready(function() {
  //change the integers below to match the height of your upper div, which I called
  //banner.  Just add a 1 to the last number.  console.log($(window).scrollTop())
  //to figure out what the scroll position is when exactly you want to fix the nav
  //bar or div or whatever.  I stuck in the console.log for you.  Just remove when
  //you know the position.
  $(window).scroll(function () { 

    console.log($(window).scrollTop());

    if ($(window).scrollTop() > 550) {
      $('#nav_bar').addClass('navbar-fixed-top');
    }

    if ($(window).scrollTop() < 551) {
      $('#nav_bar').removeClass('navbar-fixed-top');
    }
  });
});

Answer 2

注意(2015):以下问题和答案都适用于Twitter Bootstrap旧的,已弃用的2.x版本.

制作和元素"粘性"的这个功能内置于Twitter的Bootstrap中,它被称为Affix.您所要做的就是添加:

<div data-spy="affix" data-offset-top="121">
  ... your navbar ...
</div>

在你的标签周围,不要忘记加载Bootstrap的JS文件,如手册中所述.数据属性offset-top告诉页面多少像素滚动(从顶部),以解决您的菜单组件.通常它只是页面顶部的空间.

注意:修复菜单时,您必须注意丢失的空间.修复意味着将其从页面图层中剪切掉并粘贴到不滚动的不同图层中.我正在做以下事情:

<div style="height: 77px;">
  <div data-spy="affix" data-offset-top="121">
    <div style="position: relative; height: 0; width: 100%;">
      <div style="position: absolute; top: 0; left: 0;">
        ... my menu ...
      </div>
    </div>
  </div>
</div>

77px我粘贴组件的高度在哪里.

Answer 3

//在html中

<nav class="navbar navbar-default" id="mainnav">
<nav>

//添加jquery

$(document).ready(function() {
  var navpos = $('#mainnav').offset();
  console.log(navpos.top);
    $(window).bind('scroll', function() {
      if ($(window).scrollTop() > navpos.top) {
       $('#mainnav').addClass('navbar-fixed-top');
       }
       else {
         $('#mainnav').removeClass('navbar-fixed-top');
       }
    });
});

以下是jsfiddle:http://jsfiddle.net/shubhampatwa/46ovg69z/

编辑:如果您只想为移动设备应用此代码,您可以使用:

   var newWindowWidth = $(window).width();
    if (newWindowWidth < 481) {
        //Place code inside it...
       }

Answer 4

这是一个不需要额外jQuery的Bootstrap 3示例..它使用AffixBootstrap 3中包含的插件,但导航栏标记自BS2以来已发生变化...

<!-- Content Above Nav -->
<header class="masthead">

</header>           


<!-- Begin Navbar -->
<div id="nav">
  <div class="navbar navbar-default navbar-static">
    <div class="container">
      <!-- .btn-navbar is used as the toggle for collapsed navbar content -->
      <a class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
        <span class="glyphicon glyphicon-bar"></span>
        <span class="glyphicon glyphicon-bar"></span>
        <span class="glyphicon glyphicon-bar"></span>
      </a>
      <div class="navbar-collapse collapse">
        <ul class="nav navbar-nav">
          <li class="active"><a href="#">Home</a></li>
          <li class="divider"></li>
          <li><a href="#">Link</a></li>
          <li><a href="#">Link</a></li>
        </ul>
        <ul class="nav pull-right navbar-nav">
          <li>
            ..
          </li>
          <li>
            ..
          </li>
        </ul>
      </div>        
    </div>
  </div><!-- /.navbar -->
</div>

工作演示/模板:http://bootply.com/69848

Answer 5

这对我很有用.不要忘记在导航栏曾经存在的地方放置一个填充div,否则每次固定/不固定时内容都会跳转.

function setSkrollr(){
    var objDistance = $navbar.offset().top;
    $(window).scroll(function() {
        var myDistance = $(window).scrollTop();
        if (myDistance > objDistance){
            $navbar.addClass('navbar-fixed-top');
        }
        if (objDistance > myDistance){
            $navbar.removeClass('navbar-fixed-top');
        }
    });
}