Affix affix.js

Example

The 'floating' of the 'top of page' link at the bottom of the screen, is a live demo of the widget.

Usage

Use the affix widget via data attributes or manually with your own JavaScript. In both situations, you must provide CSS for the positioning of your content.

Positioning via CSS

The affix widget toggles between three classes, each representing a particular state: .affix, .affix-top, and .affix-bottom. You must provide the styles for these classes yourself (independent of this widget) to handle the actual positions.

Here's how the affix widget works:

• To start, the widget adds .affix-top to indicate the element is in its top-most position. At this point no CSS positioning is required.
• Scrolling past the element you want affixed should trigger the actual affixing. This is where .affix replaces .affix-top and sets position: fixed; (provided by Figuration's CSS).
• If a bottom offset is defined, scrolling past it should replace .affix with .affix-bottom. Since offsets are optional, setting one requires you to set the appropriate CSS. In this case, add position: absolute; when necessary. The widget uses the data attribute or JavaScript option to determine where to position the element from there.

Follow the above steps to set your CSS for either of the usage options below.

Via Data Attributes

To easily add affix behavior to any element, just add data-cfw="affix" to the element you want to spy on. Use offsets to define when to toggle the pinning of an element.

<div data-cfw="affix" data-cfw-affix-top="60" data-cfw-affix-bottom="200">
  ...
</div>

Via JavaScript

Activates an element to be affixed. Accepts an optional options object.

Call the affix widget via JavaScript:

$('#myAffix').CFW_Affix({
  top: 100,
  bottom: function() {
    return ($('.footer').outerHeight(true));
  }
});

Options

Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-cfw-affix-, as in data-cfw-affix-top="200".

$('#myAffix').CFW_Affix({
    top: 10
});

Methods

Method calls should be made on the affix element.

$('#myAffix').CFW_Affix('checkPosition');

Events

CFW's affix widget exposes a few events for hooking into affix functionality.

$('#myAffix').on('affix.cfw.affix', function() {
  // do something...
});