[news.eclipse.platform.rcp] [jface.viewers] May CellLabelProvider.update

[Daniel Krügler <dsp@xxxxxxx>]

Hello,

in a recent thread

"[jface.viewers] How do discriminate active and non-active links
in ColumnViewer?"

a HyperlinkColumnLabelProvider was demonstrated to by easily
implementable on top of the user-drawing ColumnLabelProvider API of
jface. A remaining problem was that I additionally wanted to simulate
the color-changes of an activated hyper-link. Thanks to Tom Schindl's 
excellent hints (again) I started with an implementation, but I'm now at
a point where I'm not sure whether I'm subverting the official API of 
CellLabelProvider and ViewerCell or not. My current idea is *not* to 
invoke Viewer.update(...) with the corresponding object of the activated 
link, but to memorize a ViewerCell of the most recent activated 
hyperlink (we find a similar apporach in e.g. the SWTFocusCellManager). 
If a mouse-move event enters a *new* cell, I need to "deactivate" the 
last one and to activate the new on, of course. It seems tempting to 
directly use the update method of the HyperlinkColumnLabelProvider with 
this previous ViewerCell (if it's item is not disposed yet) as argument
and similarly to use the same method again for the newly entered
hyperlink cell. Current experiments indicate that this seems "to work".

My question is: Is this a feasible usage of the CellLabelProvider API?
I have not seen any contradictory documentation but I'm a bit uncertain,
because I could not find any public usage of this method except for
the viewer, which also does some additional work.

Even if turns out not to be an API abuse, does anyone have an idea of a
more reliable of efficient way to realize that?

Thanks & Greetings from Bremen,

Daniel Krügler