[IxDA Discuss] UI design for digital books with extensive footnotes

[Luke Ball]

>>> ...but you could also
>>> consider having onMouseOver actions that open floating windows that
>>> contain the footnote, doing an XmlHttpRequest to get the footnote
>>> itself.
>> Actually, this wouldn't be a good use of mouseOver, as you would
>> likely accidentally open a lot of floating windows just by moving
>> your mouse across the page. This would also suggest that they would
>> close automatically when the mouse leaves the area, which would
>> easily be done accidentally while the user is trying to read the
>> footnote.

It occurs to me that in addition to reading a footnote, user may want  
to be able to select the footnote text to copy and paste. This might  
eliminate (or at least complicate) the rollover approach.

Perhaps do the same flyout/popup technique, but with the onclick  
event rather than onmouseover. (there could be an explicit "close"  
command in the window). There's still a lot of directness {good} to  
clicking the footnote and seeing the explanation right there, with no  
eye movement. But users only see the footnotes they want to see. If  
the footnote text is extremely long, you can build a scrolling  
mechanism into the flyout pane.

I can only assume that a more direct approach like this is preferable  
to a two-pane version (wherein the user has to look down to read the  
footnote, then back up to re-find their place and continue reading).  
The two-pane makes sense only if the user needs to cross-reference  
the primary text and the footnote simultaneously, and if you can  
presume that they are constantly interested in reading the footnotes.

My 2¢, at least.

Luke Ball

PS. you could even add some "scent" to the footnote by giving a  
little clue on mouseover "click to view footnote", or perhaps the  
first line of the footnote. Also make sure the target is larger than  
the traditional superscripted numeral.