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Book Overview & Buying
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Table Of Contents
HTML5 Multimedia Development Cookbook
By :
"When authors use the
canvaselement, they must also provide content that, when presented to the user, conveys essentially the same function or purpose as the bitmapcanvas. This content may be placed as content of thecanvaselement. The contents of thecanvaselement, if any, are the element's fallback content." - WHATWG HTML5 Specification
What happens if someone viewing your brilliant new canvas application is using an older browser and is unable to recognize your coding genius? Or what happens when someone uses assistive technologies? Let's take a look.
If, for some reason, a user's browser won't support the new canvas element, it's up to us as developers to give them something valuable instead.
Here we can use an image as fallback.
<canvas id="clock" width="200" height="200"> <img src="images/clock.gif" width="200" height="200" alt="clock"/> </canvas>
Or text:
<canvas id="clock" width="200" height="200"> <p>clock<...
Change the font size
Change margin width
Change background colour