Lógica de funcionamiento de procesos

Like images, color can enhance the aesthetic of a website. If used correctly, it will pose no problems to persons with disabilities. If used in excess, it may be distracting. If used as the only means of conveying information, it can be a big obstacle to navigation. We often rely on color to indicate links, highlight information, or to organize content into categories. A student who is color blind may not see the red color indicating a link to another page, for example. A simple question to be posed while planning the structure for content display would be “If I could only see a black and white version of this page, could I still understand all the information and navigate all the controls?” It is not a crime to use color, as long as it is not the only way to communicate. There are other ways to emphasize certain points, such as making text bold. Text links could be underlined. Preferably, however, if a number of text links are to be included in a page, a better solution might be to repeat the information at the bottom of the page, under a title such as “Links to Additional Information.”

Link

Aside from what has already been said about using images and color to indicate links, there are other conventions that facilitate usability and accessibility. For

example, providing the user with the possibility to skip navigational links is very useful to persons utilizing a screen reader. As previously mentioned, it may be very time-consuming for a blind person to navigate a page that includes menus with links at the top. While a sighted person can focus directly on the main content of a page, a person using a screen reader will have to listen to all the items on the menu before being able to go to other sections of the page. Although this may facilitate orientation the first time someone accesses a given site, it becomes a waste of time on repeated visits. A solution to this problem is the use of an anchor (also known as “bookmark” in FrontPage®) that allows the user to skip navigational links and go directly to the main content of the page. This anchor can be displayed on the very top of the page (with the target immediately before the main content section) or can be hidden from sighted users by a picture or background colors containing html code that the screen reader identifies as the anchor command.

Tables

It is not advisable to use tables (i.e., lay-out tables) simply to format information that does not need to be read as a table. When thinking about using a table, faculty should ask how the information would read after being “linearized” (read from top to bottom, left to right). When tables are necessary (i.e., data tables), certain conventions should be followed to make sure that the person relying on auditory output can integrate the information displayed on each row and column. The most important features are the header element <th> and the

scope attribute, which indicate to the reader which cells are intended as

headings and which ones are row or column headers. For more complex tables, where information is not aligned simply at the intersection of one main column header and row header, the header attribute should also be considered. Two other attributes that can greatly enhance understanding of tables are the caption and the summary attributes. As the term indicates, a caption attribute briefly describes the contents of the table. For example, the caption of a table might read “Increase in the Older Population in the United States by Cohort in the Twentieth Century.” Similarly, the summary attribute would provide an idea of the purpose and organization of the table contents. Such a summary might say “This is a three columns and three rows table, depicting the numbers of older adults in the United States, ages 65 to 74, 75 to 84, and 85 plus, in 1900, 1950, and 1999.” Because specific coded examples of these features would take more space than what is available for this chapter, readers interested in specific

html coding for these attributes can refer to the books on web accessibility listed under Resources or visit websites from organizations such as the W3C (www.w3c.org) or WebAIM (www.webain.org).

Frames

As previously mentioned, frames are not always interpreted correctly by software packages used by students with disabilities. The same may be true for a student using a text only browser. Most experts suggest that designers find alternatives to the frame layout; if this is not feasible, the noframes attribute should be added to the html code so that the user can access the same information in an alternate format. A caution often associated with advice about the noframes attribute is to ensure that the content in alternative noframes pages and the content of the regular pages are updated simultaneously to avoid discrepancies in information. Frames should be given titles that help the user understand their purpose and decide whether or not to read its contents.

Forms

When interactive forms are used, it is important to make sure that the user is able to control input even if not using a regular mouse to point and click. If a file cannot be accessed by the arrow keys, some students with physical limitations may not be able to enter the required information. Forms are also tricky for individuals using screen readers, particularly if they use a variety of elements such as radio buttons, pull-down menus, and cells for entering text information. Often these elements are images, and some readers may have a difficult time identifying them if a text descriptor is not used to define the expected commands for data entry and submission. Labeling the input type as text, checkboxes, or buttons, identifying text areas for data entry, or indicating which options are available to be checked can make desired actions much easier for a screen reader user to grasp. Like tables, forms can be a complex component for faculty not experienced in writing programming code, so it is recommended that resources providing step-by-step design instructions and examples be con- sulted prior to engaging in this task.