Navigation Bars Made Easy
By Lincoln D. Stein
Keep the user oriented, advise Web style guides. Use a navigation bar to help users find their way around your site.
Good advice, but how are we to implement it? For a long time now, I've had my eye on navigation systems. I particularly like those implemented as a table of contents running down a strip on the left-hand side of the screen. As the user moves from page to page, the navigation strip updates to show the user's current position. By clicking on the headings, the user can rapidly jump to the relevant page.
In the past, good navigation systems were tedious to generate. Each HTML page had to include the navigation bar in the correct position, size, and state. If the bar wasn't correctly positioned, the illusion of a constant element would be lost. If a new set of pages were added to the site, all the other pages had to be revised to reflect the changed structure. Automatic HTML generators, server-side includes, and CGI scripts all helped make navigation bars more practical, but each system had its drawbacks.
This changed with the introduction of frames and JavaScript in Navigator 2.0. Frames make it possible to maintain a list of links in one frame that, when selected, change the content of the other -- half the navigation-bar battle. JavaScript makes it possible to generate navigation bars automatically and to update the appearance of the bar as the user moves from location to location.
In the past year, a half dozen JavaScript-based navigation systems have been released.
