Creating Websites for the 4630/4630SW IP Telephone
Design Guidelines
B-11
Images 5
The use of images in a web page is always a concern. For example, a page with many images can
cause downloading to be slow. While this is still a concern in the phone, the size of an image has a
much greater effect. Memory in the browser, and in the phone in general, is limited. Each image
will use a sizable amount of memory, and the browser may become overwhelmed. An image
should only be used if it is essential to a page.
Images also fall into the realm of fixed-width objects. All images should be checked to verify that
they don’t cause a horizontal scrollbar to be added. An image may be scaled down by the browser,
by setting the width and height attributes of the <img> tag. The designer may instead choo se to
scale the images when setting up the web site. This avoids forcing the browser to deal with the
sizing (using the width and height attributes scales the image after it is downloade d by the
browser) and speeds up downloading of the images. Finally, reducing the size of the image
reduces the amount of memory used.
Animated GIF images are a bad idea since they use up quite a bit of memo ry. Additionally,
because of the persistence of the LCD screen, animated images tend to smear in the browser and
lose their effectiveness. Hence, animated GIFs are considered "not suppo rted" with this phone.
Frames 5
While frames provide a useful method of browsing a series of pages (via a contents frame and a
document text frame), they also use up real estate, just like scrollbars. Even i f the frame
decorations were all turned off, the frame containing the majority of the document tex t now suffers
the problems discussed above; the width of the frame is smaller, and the chances of adding a
horizontal scrollbar have increased. Additionally, a single line of text will have fewer character s
viewable, and the page becomes even more difficult to read and comprehend. Usi ng simple
navigation buttons at the top and bottom of the page, or even at the top and bottom of each section
should make up for the missing contents frame.
The interaction between frames and scrollbars is another important area of con cern. While most
browsers manage scrolling within each frame independently, the 4630 Web Access Application
only scrolls the entire (single) window. This moves the user’s view of the frames as a whole, but it
does not scroll any of the data in individual frames. There will likely be data in frames that can
never be seen.
The combined problems of minimal screen real estate and the scrolling issu es really makes
frames something simply to avoid.