Reducing the height of the navigation bar when user scrolls the page - html

Question

I want to add a navigation bar which is initially long in height. and when the user scrolls the height reduces and the logo becomes small. I am using Bootstrap and my code is displayed as shown below.
Can someone please help me edit the code so i can reduce height of the navigation bar when scrolling the page.
<div class="navbar-header">
<button type="button" class="navbar-toggle" data-toggle="collapse"
data-target="#bs-example-navbar-collapse-1">
<span class="sr-only">Toggle navigation</span> <span
class="icon-bar"></span> <span class="icon-bar"></span> <span
class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">project a</a>
</div>
<!-- Collect the nav links, forms, and other content for toggling -->
<div class="collapse navbar-collapse"
id="bs-example-navbar-collapse-1">
<ul class="nav navbar-nav">
<li class="active">Link</li>
<li>Link</li>
<li class="dropdown"><a href="#" class="dropdown-toggle"
data-toggle="dropdown">Dropdown <b class="caret"></b></a>
<ul class="dropdown-menu">
<li>Action</li>
<li>Another action</li>
<li>Something else here</li>
<li class="divider"></li>
<li>Separated link</li>
<li class="divider"></li>
<li>One more separated link</li>
</ul></li>
</ul>
<form class="navbar-form navbar-left" role="search">
<div class="form-group">
<input type="text" class="form-control" placeholder="Search">
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
<ul class="nav navbar-nav navbar-right">
<li>Link</li>
<li class="dropdown"><a href="#" class="dropdown-toggle"
data-toggle="dropdown">Dropdown <b class="caret"></b></a>
<ul class="dropdown-menu">
<li>Action</li>
<li>Another action</li>
<li>Something else here</li>
<li class="divider"></li>
<li>Separated link</li>
</ul></li>
</ul>
</div>
<!-- /.navbar-collapse -->
</div>
<!-- /.container-fluid -->
</nav>

Answer 1

This will help you achieve what you want.
jsFiddle
$(function(){
$('#navigation-bar').data('size','big');
});
$(window).scroll(function(){
var $nav = $('#navigation-bar');
if ($('body').scrollTop() > 0) {
if ($nav.data('size') == 'big') {
$nav.data('size','small').stop().animate({
height:'40px'
}, 600);
}
} else {
if ($nav.data('size') == 'small') {
$nav.data('size','big').stop().animate({
height:'100px'
}, 600);
}
}
});
this is from the question here
Update
Based on the bootstrap structure
I have written the code . Check this out jsFiddle
HTH.