Progress bar (progress polyfill) - nschonni/wet-boew GitHub Wiki

français

Table of Contents Background Purpose Rationale Implementation Parameters/Options Value Parameter Max Parameter Example Code Task in Progress Completed Task Task of Unknown Progress Examples Development Known Issues Version History References

Background

Project Lead: Laurent Goderre (@LaurentGoderre)

Purpose

The HTML5 progress element allows to display the progress of a task. Because some browsers do not support this functionality natively, this polyfill emulates the same functionality using generic HTML and WAI-ARIA.

Rationale

Browsers that do not support the progress element natively ignore the progress bar and therefore, nothing is displayed and its content is not exposed to assistive technologies. This polyfill ensures that the progress is visually conveyed through a progress bar and exposed to assistive technologies by adding ARIA.

Implementation

To use the polyfill, a standard progress element must be used. In cases where browser don't support the progress element, the polyfill is automatically loaded.

Parameters/Options

The progress bar polyfill accepts two parameters: max and value. Neither of these parameters are required.

Value Parameter

This parameter represent the progress of the task and can be any decimal number between 0 and the max value. If value is omitted, the progress bar is considered to be undeterminate, which means that there is no indication on the actual progress of the task.

Max Parameter

This parameter represent the maximum progress for the task. When the value parameter is set to the maximum value, the task is considered complete. The max parameter can be any positive decimal number. If the parameter is omitted, the default value of 1.0 is assumed.

Example Code

The working examples are located here

Task in Progress

<progress value="25" max="100" />

Completed Task

<progress value="50" max="50" />

Task of Unknown Progress

<progress />

<progress max="50" />

Examples

Development

The progress bar is dependent upon native support for the HTML5 progress element or the progress polyfill.

The code for the progress bar is located in several places within the source folder of WET:

js/polyfills/progress.js - contains the JavaScript code for the progress polyfill
js/sass/includes/_progress.scss - contains the CSS for the progress polyfill
js/images/progress/ - contains the images for the progress polyfill