JQuery RelativeFixed Plugin

index.html

<div class="container">
  <div class="relativeFixed">
    I'm fixed relative to my parent
  </div>
  <div class="content">
    <h1>HTML Ipsum Presents</h1>
	       
<p><strong>Pellentesque habitant morbi tristique</strong> senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. <em>Aenean ultricies mi vitae est.</em> Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, <code>commodo vitae</code>, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. <a href="#">Donec non enim</a> in turpis pulvinar facilisis. Ut felis.</p>

<h2>Header Level 2</h2>
	       
<ol>
   <li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
</ol>

<blockquote><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vivamus magna. Cras in mi at felis aliquet congue. Ut a est eget ligula molestie gravida. Curabitur massa. Donec eleifend, libero at sagittis mollis, tellus est malesuada tellus, at luctus turpis elit sit amet quam. Vivamus pretium ornare est.</p></blockquote>

<h3>Header Level 3</h3>

<ul>
   <li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
</ul>

<pre><code>
#header h1 a { 
	display: block; 
	width: 300px; 
	height: 80px; 
}
</code></pre>
  </div>
</div>

JQuery-RelativeFixed-Plugin.markdown

JQuery RelativeFixed Plugin

Fixing an element relative to the parent which has overflow scroll.

A Pen by Surendra on CodePen.

License.

script.js

//plugin to relatively fix the elements in a container with scroll
$.fn.relativeFixed = function (options) {
  if (this.length == 0)
    return this;

  var defaults = {
    parentDiv: ''
  }
  var plugin = {};
  var el = this;
  var init = function () {
    //add class to the parent div
    el.parent().addClass('aps-relativeFixed-parent');
    plugin.settings = $.extend(defaults, options);
    if (plugin.settings.parentDiv == '') {
      //store the parent div object
      plugin.settings.parentDiv = el.parent('.aps-relativeFixed-parent');
    }
    else {
      plugin.settings.parentDiv = $(plugin.settings.parentDiv);//create a jquery object for parentDiv
    }
    el.css({
      'position': 'absolute'
    });

    //get the element current offset
    plugin.currentOffsetTop = el.offset().top - plugin.settings.parentDiv.offset().top;
    //attach event of scroll on the parent div
    $(plugin.settings.parentDiv).on('scroll', function () {
      var newOffset = plugin.currentOffsetTop + plugin.settings.parentDiv.scrollTop();
      el.css({
        'top': 0,
        'bottom': 'auto',
        'transform': 'translate3d(0,' + newOffset + 'px,0)',
        '-webkit-transform': 'translate3d(0,' + newOffset + 'px,0)',
        '-moz-transform': 'translate3d(0,' + newOffset + 'px,0)',
      });
    }).scroll();
  }
  el.destroy = function () {
    el.removeAttr('style');
    plugin.settings.parentDiv.removeClass('aps-relativeFixed-parent');
    plugin.settings.parentDiv.off('scroll');
  }
  init();
  return this;
}
//end plugin

//calling the plugin
$('.relativeFixed').relativeFixed();

style.css

*{
  -webkit-box-sizing:border-box;
  -moz-box-sizing:border-box;
  box-sizing:border-box;
}
body{
  font-size:16px;
  font-family:"Verdana",sans-serif;
}
.container{
  background:#ccc;
  width:600px;
  height:400px;
  margin:0 auto;
  overflow-y:auto;
  position:relative;
  padding:20px 0;
}
.relativeFixed{
  position:absolute;
  left:12px;
  top:120px;
  width:100px;
  padding:20px;
  background:#333;
  font-size:14px;
  color:#fff;
}
.content{
  background:#fff;
  width:80%;
  margin:0 auto;
  padding:20px;
}