Cool thanks for the pre redisplay suggestion.
On Mar 7, 2014 4:26 PM, "Stefan Monnier" <monnier@iro.umontreal.ca> wrote:

> > so the code I had written was able to detect whether the mode-line was
> > being displayed in the active window or not.
>
> IIUC your old code was not correct in some circumstance (maybe in the
> presence of multiple frames, can't remember), but indeed the change in
> Emacs-24.4 (which was made to fix another problem) breaks such hacks.
>
> The best I can offer so far goes along the following lines:
>
> 1- use post-command-hook (or better yet pre-redisplay-function) to set
>    a global variable `my-selected-window'.
> 2- use that variable instead of (selected-window) in your modeline :eval
> code.
>
>
>         Stefan
>