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SkipTo logo

[email protected] Page Script

See the Authors section for more information.

SkipTo is a replacement for your old classic "Skip To Main Content" link, (so please use it as such)! The SkipTo creates a drop-down menu consisting of the links to important landmarks and headings on a given web page identified by the author. Once installed and configured, the menu makes it easier for keyboard and screen reader users to quickly jump to the desired region of a page by simply choosing it from the list of options.

NOTE: SkipTo 5 is a total rewrite of SkipTo 4 to support custom web components and solidify SkipTo 5 to promote the proper understanding and use of headings and landmark regions for improving accessibility. The SkipTo 5 code is a new code base to support Javascript Modules for improved development and maintenance of SkipTo features.

Benefits

  • Modern way to conform to the "Bypass Blocks" requirement of the Web Content Accessibility Guidelines.
  • Screen reader users can get a higher level navigation menu without having to use the screen reader landmark and header navigation commands which typically include longer lists of lower level headings and less used landmarks.
  • Keyboard only users can more efficiently navigate to content on a page.
  • Speech recognition users can use the menu to more efficiently navigate to content on a page.
  • When the "Skip To Content" menu button is visible when the page is loaded everyone can use it to identify and navigate to important regions on a page.
  • Authors can configure SkipTo to identify the most important regions, ideally about 7-12 items to make it easier for people to read the list and choose an option. Remember the more items, the longer it will take for the user to identify which item they want to choose.

Example Screen Shot

Websites using SkipTo

There are two main ways to use the menu button for SkipTo in a page. In the default configuration the menu button is always visible making it useful to everyone to easily find and navigate to the important content regions identified by the author. This is similar to how curb cuts help more than just people using wheelchairs. It is also easier for people using voice recognition to activate the button using the "click skip to content" command and use similar voice commands to activate SkipTo menu items. The "popup" option is the more traditional approach to fulfilling the "bypass bocks" requirement of the Web Content Accessibility Guidelines, but this option makes the feature less visible to people who might benefit.

Visible Menu Button (default)

Popup Menu Button

NOTE: Popup menu button option is available through configuration of SkipTo when it is loaded.

How it works

  1. The SkipTo menu button should be the first tabable element on the page, and by default the button is visible, but can be configured to "popup" when the button becomes receives focus.
  2. Once the keyboard focus is on the menu button, pressing the ENTER, SPACE, DOWN ARROW or UP ARROW keys will pull down the list of important landmarks and headings on the page. The button is based on the ARIA Authoring Practice design pattern for menu button.
  3. Use arrow keys to select your choice and press ENTER to move focus to the section of the page.

Shortcut key

A shortcut key can be used to open the SKipTo menu from anywhere on the page. Version 5 changes the shortcut key operation from using the HTML accesskey attribute to use a scripted method to improve consistency of the shortcut keys between browsers and to support screen reader users, since some screen readers do not support accesskeys.

To use the "SkipTo" shortcut key, you would press either alt + 0 (Windows/Unix/Linux) or Option + 0 (macOS). macOS does not have an Alt key, so the Option key is used as the modifier. The access keys are the same for Firefox, Chrome and Safari on the same operating system.

  • Alt+0 : Windows, Unix and Linux.
  • Option+0 : macOS.

Adding to Website

All you need are either skipto.js or skipto.min.js from the "dist/" directory of this repository. Please note that skipto.min.js is a minified (a lighter version) of the script.

Local File on Your Web Server

Copy the skipto.js or skipto.min.js to the file system of your web server and reference it from your web page or templates using a script tag, as follows:

<script src="https://[path to Javascript files]/skipto.min.js"></script>

CDN Service

The easiest way is to include a reference to skipto.min.js on your HTML page or template is through the CDN service, as follows:

github.com CDN service:

<script src="https://skipto-landmarks-headings.github.io/page-script-5/dist/skipto.min.js"></script>

or

University of Illinois CDN service:

<script src="https://cdn.disability.illinois.edu/skipto.min.js"></script>

NOTE: CDN referenced files may not be available to computers behind firewall protected networks.

Reporting Issues

Please use Github issues to report problems, ask support questions or offer feature enahancement ideas.

Configure Options

All settings have a default value, a configuration object can be used to change the default values.

Options for adding the button element

The following options are useful for identify where the menu will be in the DOM structure of the page and which elements will be used as the container for the menu button. The options are of type string.

Property default Description
displayOption 'static' Values of static, fixed or popup are defined. The value static the button is always visible, the value fixed the button is always visible at the top of the page even when the page scrolls, and the value popup is used the button is initially not visible, but becomes visible when it receives focus.
attachElement 'body' A CSS selector for identifying which element to attach the menu button container.
customClass none CSS class added to the container div element. Can be used for customize styling of the button and menu with author supplied stylesheet.
altShortcut '0' Shortcut character for Windows/Linux/Unix when the alt key is pressed to open the menu.
optionShortcut 'º' Shortcut character for macOS when the option key is pressed to open the menu.

Button Positioning

Property Type Default Description
positionLeft length 46% The position of the "Skip To Content" button from left margin.

Button Font Family and Font Size

Property Type Default Description
fontSize CSS font size inherit Set the CSS font-size using the configuration object.
fontFamily CSS font string inherit Set the CSS font-family using the configuration object.

Identifying Landmarks and Headings for the menu

The landmarks and 'headings' options are a space separated list of tag and landmark region names to identify the important landmark regions and headings on the page for the purpose of keyboard navigation. The list of landmarks and headings should be relatively short, the more items the menu contains the more time the user will need to scan and navigate to the section they want to "skip to". The values are considered tokens to maximize compatibility with version 4 CSS selectors for these properties.

The options are of type string.

Property Default Description
landmarks 'main search navigation complementary' A space separated list of landmark names. Allowed values include: banner, complementary, contentinfo, main, navigation, region and search
headings 'main h1 h2' A space separated list of heading tags, "main" is included only headings contained in the main. Allowed values include: h1, h2, h3, h4, h5, h6 and main

Color Theme Options

A color theme sets all the color options defined by the theme.

Property Type Default Description
colorTheme string default A predefined color scheme for skipTo

Current Color Theme Values:

  • 'aria' : Used in ARIA Authoring practices

  • 'illinois': Used by the University of Illinois at Champaign/Urbana

  • 'uic' : Used by the University of Illinois at Chicago

  • 'uillinois' : Used by the University of Illinois Administration

  • 'uis' : Used by the University of Illinois at Springfield

  • If you would like a them added for your organization, please file an issue with the desired colors

Colors used for Button and Menu styling

Color values must use CSS color values, for example #8AF, rgb(40, 50, 90), #a0bf32, blue.

Property Type Default Description
buttonTextColor Color #1a1a1a Color of text for "Skip To Content" button.
buttonBackgroundColor Color #eeeeee Background color of text for "Skip To Content" button.
focusBorderColor Color #1a1a1a Border color for items with keyboard focus.
menuTextColor Color #1a1a1a Menu text color
menuBackgroundColor Color #dcdcdc Menu background color.
menuitemFocusTextColor Color #eeeeee Menuitem text color when a menuitem has focus.
menuitemFocusBackgroundColor Color #1a1a1a Menuitem text background when a menuitem has focus.

NOTE: Make sure colors meet the color contrast requirements of WCAG 2.1 for text

Internationalization (I18N)

The text labels and messages can be updated through configuration to local language requirements.

Button Labeling

The labels and messages can be localized for specific languages or updated to reflect custom selectors.

Property Default Description
buttonLabel 'Skip to Content' Change the label for the button.
altLabel 'Alt' Label for modifier key for Windows and Unix/Linux operating systems
optionLabel 'Opt' Label for modifier key for macOS operating systems
altShortcut '0' Shortcut character used in combination with the alt key for opening the menu
optionShortcut 'º' Character generated by macOS when the option key is pressed with the shortcut key.
altButtonAriaLabel 'Skip To Content, shortcut Alt plus $key' aria-label template for button when the OS uses alt key
optionButtonAriaLabel 'Skip To Content, shortcut Option plus $key' aria-label template for button when the OS uses option key (e.g, macOS)

Menu, Group and Menuitem Labeling

The labels and messages can be localized for specific languages or updated to reflect custom selectors.

Property Default Description
menuLabel 'Landmarks and Headings' Change the label for the menu.
landmarkGroupLabel 'Landmark Regions' Menu group label for landmarks .
headingGroupLabel 'Headings' Menu group label for headings.
mofnGroupLabel '$m of $n' Provides information on the number of items that are displayed and the total number of items in the document. The information is added to the landmark and heading group labels.
headingLevelLabel 'Heading level' Used for aria-label to improve labeling of heading menu items for screen reader users.
mainLabel 'main' The label in the menu for main landmarks
searchLabel 'search' The label in the menu for search landmarks
navLabel 'navigation' The label in the menu for navigation landmarks
asideLabel 'aside' The label in the menu for complementary landmarks
footerLabel 'footer' The label in the menu for contentinfo landmarks
headerLabel 'header' The label in the menu for banner landmarks
formLabel 'form' The label in the menu for form landmarks
msgNoLandmarksFound 'No landmarks to skip to' Message for when no landmarks are found.
msgNoHeadingsFound 'No main headings to skip to' Message for when no headings are found.

Deprecated Configuration Properties from Version 4

The following properties were deprecated from previous versions of SkipTo and will be ignored if defined.

  • actionGroupLabel
  • actionShowHeadingsHelp
  • actionShowSelectedHeadingsLabel
  • actionShowAllHeadingsLabel
  • actionShowLandmarksHelp
  • actionShowSelectedLandmarksLabel
  • actionShowAllLandmarksLabel
  • actionShowSelectedHeadingsAriaLabel
  • actionShowAllHeadingsAriaLabel
  • actionShowSelectedLandmarksAriaLabel
  • actionShowAllLandmarksAriaLabel
  • buttonTitle
  • buttonTitleAccesskey
  • containerElement
  • containerRole

Example Settings

You can custiomize SkipTo to the features of your website by using a configuration object. The following is a sample configuration:

<script>
var SkipToConfig =  {
  landmarks: 'main search navigation',
  headings: 'main h1 h2 h3',
  colorTheme: 'illinois'
};
</script>

NOTE: Configuration objects in version 4.x are still supported for compatibility with existing installations. Version 5.0 is providing a less complex object for customizing SkipTo.

HTML, Classes and Ids for custom styling

The source code in this section is for developers to understand the HTML, classes and ids used in the SkipTo menu button and menu for use in custom styling.

<div class="skip-to">
  <!--
  //
  // Menu Button
  //
  -->
  <button
    aria-haspopup="true"
    aria-expanded="true"
    aria-label="Skip to content, shortcut Alt plus 0">
    Skip To Content (Alt+0)
  </button>
  <!--
  //
  // ARIA enabled menu
  //
  -->
  <div role="menu">
    <!--
    //
    // Landmark group label and menu items
    //
    -->
    <div id="id-skip-to-group-landmarks-label"
      role="separator">
      Important Landmarks
    </div>
    <div role="group"
      aria-labelledby="id-skip-to-group-landmarks-label" id="id-skip-to-group-landmarks">
      <div role="menuitem"
        class="landmark skip-to-main skipto-nesting-level-0"
        data-id="1">
        <span class="label">Main</span>
      </div>
      <div role="menuitem"
        class="landmark skip-to-nav skipto-nesting-level-0"
        data-id="2">
        <span class="label">Navigation: SkipTo test pages</span>
      </div>
      <!--
      ... more menu items ...
      -->
    </div>
    <!-- End Landmarks Group -->

    <!--
    //
    // Heading group label and menu items
    //
    -->
    <div id="id-skip-to-group-headings-label"
      role="separator">
      Important Headings
    </div>
    <div role="group"
      aria-labelledby="id-skip-to-group-headings-label"
      id="id-skip-to-group-headings">
      <div role="menuitem"
        class="heading skip-to-h1"
        data-id="9"
        data-level="1">
        <span class="level"><span>1</span>)</span>
        <span class="label">Example Content</span>
      </div>
      <div role="menuitem"
        class="heading skip-to-h2"
        data-id="10"
        data-level="2">
        <span class="level"><span>2</span>)</span>
        <span class="label">Pastrami</span>
      </div>
      <!--
      ... more menu items ...
      -->
    </div>
    <!-- End Headings Group -->
  </div>
</div>

Notes

  • Parameters are optional.
  • SkipTo will be attached to the headerelement as the first child by default. If the headerelement is not present, it will be attached as the first child of the body element on the page. The attachment can be changed using the "attachElement" parameter.
  • When the custom class is specified (see the customClass parameter), the user can override the style:
nav#skip-to.MyCustomClass {
  background:  red;
  left: 50px;
  top: 50px;
}

Compiling CSS and JavaScript

You may feel slightly adventurous and decide to change some colors by creating a built-in color theme or even enhance the script with your changes. Once you do this, here is how you compile the skipTo script for production.

git clone https://github.com/skipto-landmarks-headings/page-script-5.git
cd page-script-5
sudo npm install grunt-cli -g
npm install
gulp
  1. You should now have a directory called dist with the necessary files in it.
  2. See instructions above on which files you need to get the SkipTo script running on your web site.

Of course, we want feedback

Please do not hesitate to raise issues and comment on Github if something doesn't work or you have ideas on how to improve the script.

Happy skipping!

Authors

Current Contributors

Jon Gunderson https://github.com/jongund

Nicholas Hoyt https://github.com/nhoyt

Prem Nawaz Khan https://github.com/mpnkhan || @mpnkhan

Previous Contributors

Ron Feathers https://github.com/rfeathers || @ronfeathers

Marc Kocher https://github.com/mdkocher || @marckocher

Brian Teeman https://github.com/brianteeman

Victor Tsaran https://github.com/vick08 || @vick08

Version History

Version 5.1.0

  • Supports including landmark regions and headings in custom web components
  • Makes the skipto container element a navigation landmark region with an accessible name
  • Deprecates the containerElement and containerRole configuration options (e.g. uses "nav" element)
  • Reorganizes the code into modules for improved development and readability
  • Switch from using grunt to gulp for building release files
  • Updated accessible name calculation
  • Added transition effect for "popup" display option when button receives focus
  • Responsive: Button text changes to skipto icon when screen width is less than 540px
  • Use template element for creating style element
  • skipto.min.js.map file is no longer generated for skipto.min.js for debugging, reference skipto.js instead for debugging needs

Version 5.0.1

  • Unify shortcut key to be consistent between browsers and to support screen reader users using the shortcut by changing the shortcut to use Javascript rather than the HTML accesskey attribute.
  • Support a scrollable menu if the list of menu items does not fit in the current window size.
  • Removed tooltip and added the shortcut key information to the button label to simplify the identification of the shortcut key.
  • Fix bug in not moving focus to "hidden" elements.
  • Fixes bug with Safari visual rendering of the menu item with focus.
  • Deprecates "All headings" and "All landmarks" option to reduce code and configuration complexity
  • Simplifies configuration object

Version 4.1.6

  • Revert the changes from 4.1.4

Version 4.1.5

  • Corrects packaging error in 4.1.4

Version 4.1.4

  • Fixes problem in failure to create the SkipTo menu due to invalid configuration

Version 4.1.3

  • Region landmarks must have an accessible name to be included as a landmark in the SkipTo menu to comply with ARIA specification for landmark regions, and will region landmarks be included after complementary landmarks in the SkipTo menu.
  • Updated landmark prefixes in menu to align with actual ARIA role names with the following changes:
    • header: => banner
    • footer: => contentinfo
    • aside: => complementary

Version 4.1.2

  • Added aria-busy="true" attribute to menu element when SkipTo is initialized and being updated with new menu items to support validators looking for required menu items for the menu role.
  • Added the optional aria-controls attribute to button element to reference the id of the menu element as defined in the W3C ARIA Authoring practices for menu button pattern.

Version 4.1.1

  • Removed aria-describedby from button, since screen readers read the accesskey information.

Version 4.1

  • Added feature for the escape key to hide tooltip when focus is on button.
  • Added new properties to set font family and font size.
  • Adding CSS properties to the .label and .level class so the inherited values from [role="menuitem"] are not overridden as easily by other stylesheets used on a page.
  • Updated moving focus to improve moving focus to visible targets within landmarks.
  • Fixed broken shortcut keys in the menu

Version 4.0.5

  • Fixes a problem introduced in version 4.0.4 when button tooltip was updated, restores support for buttonTitle and buttonTitleWithAccesskey configuration properties.

Version 4.0.4

  • Popup tooltip shows accesskey to open menu when button on hover or focus.
  • Popup tooltip is only displayed when a known accesskey is supported by the browser and device operating system.
  • Popup tooltip supports high contrast operating system settings.
  • Action menu items are disabled by default.
  • M of N items in landmark or heading list is disabled by default.
  • CDN reference to skipto.min.js is now available from University of Illinois.
  • Changed the way the button is hidden visually in "popup" mode not to create wider pages

Version 4.0.3

  • Fixed bug in using role description as a class name for menuitem
  • Fixed bug in setting menuTextColor property.
  • Updated documentation.

Version 4.0.2

  • Changed landmarks from using the tag name in the class list to custom skip-to prefixed tag name.
  • Fixed bug when no landmarks or headings found.
  • Simplified color configuration options.

Version 3.1.4

  • Fixed Joomla configuration option.
  • Added m of n to landmark and heading group labels.

Version 3.1.3

  • Added "fixed" to the displayOptions customization.

Version 3.1.2

  • Fixed bug in moving focus for landmarks.

Version 3.1.1

  • Changed "Important" to "Selected" landmarks and headings.

Version 3.1

  • Added aria-label for action menu items to make the label screen reader friendly
  • For heading menuitems, use aria-label to make the label more like a screen reader
  • Use element names as landmark labels instead of landmark names
  • Support aria-roledescription for labeling landmark roles in menu
  • Nested landmarks and header levels are indented
  • Added actions to toggle between "Important" and "All" landmarks and headings.
  • Added additional keyboard shortcuts in the menu based on heading level.
  • Added more information about accesskey in help.
  • Fixed bugs in 3.0

Version 3.0

  • Removed id selector options, if ids are needed they could be added to the landmarks selector
  • Removed need to call initialization function
  • Removed support for Internet Explorer
  • Improved code readability and ARIA support, by removing complexity needed to support Internet Explorer
  • Improved configuration of button and menu labeling
  • Add configuration of button and menu colors, without adding a stylesheet
  • Update the landmarks and headings in the menu by querying the DOM every time the menu is opened
  • Reduced markup conflicts by using a data attribute rather than an IDREF for targets
  • Reduced changes in page markup by only applying tabindex=-1 when focus is moved to a target
  • Updated the function for testing if an element is visible

Version 2.1

  • Ignore hidden landmarks and headings, based on:
    • CSS: display: none
    • CSS: visibility: hidden
    • HTML5 hidden attribute
    • ARIA 1.0 aria-hidden=true attribute
    • ARIA 1.0 role=presentation attribute
    • any element that is less than 4 pixels high or wide

Version 2.0

  • Support for HTML5 section elements
  • Calculate accessible names for landmarks and headings
  • Updated menu to separate headings from landmarks
  • Created default for main content
    • main element
    • [role=Main]
  • Created default for HTML5 sections
    • nav element
  • Updated defaults for landmarks
    • [role=navigation]
    • [role=search]
  • Updated defaults for headings
    • h1 element
    • h2 element

Copyright and license

Copyright 2022, Jon Gunderson, University of Illinois and PayPal under the BSD license.