jQuery.scrolling

This plugin adds the scrollin and scrollout events to jquery: these events will fire when any given element becomes visible/invisible in the browser viewport, allowing you to:

• automatically or programmatically show/hide any HTML content as soon as it comes inside or outside the browser viewport (i.e. when the user scrolls to them).
• prevent unnecessary processing for content that is hidden or is outside of the browser viewport.
• trigger a custom function or behaviour (such as loading external AJAX content) when a certain point of the page is reached.

and more.

The plugin also supports frame, iframe and/or dynamically-generated content.

Requires jQuery 1.7 or above.

Home Page

For the latest package, documentation, API and support please refer to the project Home Page.

Installation

Installing the plugin is easy: all you need to do is download the latest version from the official project page (tar or zip): unpack the archive somewhere, copy the .js file in your website javascript folder and add the following line to the head block of your web page:

    <script type="text/javascript" src="/yourpath/jquery.scrolling.js"></script>

Usage

Activate the plugin for one or more elements defined by a selector:

    $('selector').scrolling(); 

Or for raw DOM nodes created using the standard jQuery syntax:

    $('<div>content</div>').scrolling(); 

Once activated, you can bind your code to the scrollin and scrollout events: they will trigger when the active element(s) will come inside the browser viewport.

    $('selector').on('scrollin', function(event, $all_elements) {
      // we reach this point as soon as the 'selector' element becomes visibile inside the browser viewport.
      // $all_elements contains all the appeared elements.
    });

    $('yourselector').on('scrollout', function(event, $all_elements) {
      // we reach this point as soon as the 'selector' element goes outside the browser viewport.
      // $all_elements contains all the disappeared elements.
    });

If you want to fire the scrollIn event for elements which are close to viewport but are not visible yet you may either:

• use the offsetTop and offsetLeft options properties during initialization.

• add the following custom data attributes offset-top and offset-left to DOM nodes.

  $('#myEl').scrolling({ offsetTop: 100 }); 
  // appear will be fired when "myEl" is 100 or less pixels
  // below browser viewport 
  

or

    <div id="myEl" data-offset-top="100">...</div>
    // same as above using data attributes.

Appear check can also be forced by calling $.checkScrolling(). This is suitable in cases when page is in initial state (not scrolled and not resized) and when you want manually trigger appearance check.

There's also a custom scrollin jQuery filter you can use for manual checking if the element is inside the viewport or not.

    $('selector').is(':scrollin')

Demo and Examples

Check the project demo page to see the most common implementation scenarios.

Related links

• Project Home Page, where you can dowload the latest version.
• GitHub repository, where you can review the source code and/or fork it to your needs.
• jquery.scrolling official page on NPM.org, the node.js repository of most jQuery plugins.
• jquery.scrolling project page on the author website.

Credits

This is a revamp/upgrade of the jquery.appear plugins respectively hosted on:

• http://code.google.com/p/jquery-appear/
• https://github.com/morr/jquery.appear

The original code has been rewritten and updated in order to support additional features, namely:

• IFrame support
• more options
• configurable values
• revised documentation
• additional samples and more.

Support

You can support this project's development by clicking on the following button.

Thanks a lot!

License

Licensed under MIT license.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.