Week+9+Readings


 * This is merely PART of the notes taken from the week 9 slides, not ALL! This is just for quick references and point forms you may want to remember, you should still study the notes in full yourself.

P** erceivable ** O** perable ** U** nderstandable ** R** obust
 * The Four POUR Principles**

Vision Disability** - low vision - colour blindness - seizure
 * - blindness

Blindness: **** - cannot scan for content - keyboard is primary method of interaction - difficult to access visual information - limitations of screen readers

- POUR**** : - **P** erceivable – detailed text descriptions for graphics, video, animation - **O** perable – fully operable with keyboard - **U** nderstandable – page has clear and consistent structure, avoiding complex tables - **R** obust – new technologies may be incompatible with AT **

Low vision: ** - cannot see without magnifier - hard to read text in graphics - cannot see pages in low contrast - **P** erceivable – make text more legible, use true text as opposed to text in graphics, use percentages rather than absolute units (pixels), maximize contrast of pages (graphics, fonts, and backgrounds)

Colour blindness: - problem in colour combinations - challenge when colour is used as the only way ton convey information - **P** erceivable – avoid colour pair problems, provide contrast between fore/background, make sure colours are not the only way to convey important information

Hearing: - problem with auditory prompts without visual signposts - lack of caption for video and audio content - **P** erceivable – to perceive auditory content: alternative text for animation, captioning, transcript, text description (eg. For audio instructions) -- allow user control of start/stop, animations, and other options

Effective Navigation Tips**

1. Build a good navigation structure - ** reduce entry points - consistent structure - sitemap - standard navigation UI **

2. Give feedback to user actions - clickable area needs to appear obvious when clickable - change cursor when appropriate - there is always an area to focus for keyboard - keyboard focus should be visible and obvious - keyboard focus and selection should have separate/unique indicators **
 * - mouse movement and keyboard focus feedback

3. Help users navigate efficiently through keyboard** - enable navigation to all elements using tab and arrow keys - provide shortcuts to important links and content - keyboard commands for menus and controls - pages are error-tolerant