Question

If you scroll down the page in the following URL, the ‘share’ div will lock onto the browser:

http://knowyourmeme.com/memes/pizza-is-a-vegetable

I’m assuming they are applying a position: fixed; attribute. How can this be achieved with jQuery?

Answer 1

You can find an example below. Basically you attach a function to window‘s scroll event and trace scrollTop property and if it’s higher than desired threshold you apply position: fixed and some other css properties.

jQuery(function($) {
  $(window).scroll(function fix_element() {
    $('#target').css(
      $(window).scrollTop() > 100
        ? { 'position': 'fixed', 'top': '10px' }
        : { 'position': 'relative', 'top': 'auto' }
    );
    return fix_element;
  }());
});

body {
  height: 2000px;
  padding-top: 100px;
}
code {
  padding: 5px;
  background: #efefef;
}
#target {
  color: #c00;
  font: 15px arial;
  padding: 10px;
  margin: 10px;
  border: 1px solid #c00;
  width: 200px;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="target">This <code>div</code> is going to be fixed</div>