Scrollspy

Scrollspy tracks certain elements and which element the user's screen is currently centered on. Our main demo of this is our table of contents on every documentation page to the right. Clicking on these links will also scroll the page to that element.

<div class="row">
  <div class="col s12 m9 l10">
    <div id="introduction" class="section scrollspy">
      <p>Content</p>
    </div>
    <div id="structure" class="section scrollspy">
      <p>Content</p>
    </div>
    <div id="initialization" class="section scrollspy">
      <p>Content</p>
    </div>
  </div>
  <div class="col hide-on-small-only m3 l2">
    <ul class="section table-of-contents">
      <li><a href="#introduction">Introduction</a></li>
      <li><a href="#structure">Structure</a></li>
      <li><a href="#initialization">Initialization</a></li>
    </ul>
  </div>
</div>

        

Initialization

  document.addEventListener('DOMContentLoaded', function() {
    const elems = document.querySelectorAll('.scrollspy');
    const instances = M.ScrollSpy.init(elems, {
      // specify options here
    });
  });
        

Options

Name	Type	Default	Description
throttle	Number	100	Throttle of scroll handler.
scrollOffset	Number	200	Offset for centering element when scrolled to.
activeClass	String	'active'	Class applied to active elements.
getActiveElement	Function		Used to find active element.

getActiveElement

This is the default function used for finding the active element where id is the id of the scrollspy element. It returns a CSS selector of the element you want marked active.

  function(id) {
    return 'a[href="#' + id + '"]';
  }
        

Methods

All the methods are called on the plugin instance. You can get the plugin instance like this:

                  const instance = M.ScrollSpy.getInstance(elem);
          

.destroy();

Destroy plugin instance and teardown

instance.destroy();
        

Properties

Name	Type	Description
el	Element	The DOM element the plugin was initialized with.
options	Object	The options the instance was initialized with.