bug#27973: 26.0.50; Feature Request - OSX - Transparent Titlebars

[Alan Third]

On Sat, Aug 05, 2017 at 05:39:03PM -0700, James Nguyen wrote:
> It looks reasonable to me, the toolbar is also transparent.
> 
> https://www.dropbox.com/s/tiy36twyut6uw73/Screenshot%202017-08-05%2017.31.42.png?dl=0
> 
> The frame color isn't adjustable since I'm setting up the colors at
> Emac's compile time so using a dark theme results in dark font in the
> title bar instead of a light one.

It seems to me there are at least two things we want here:

  1. Setting transparency of UI elements. Possibly with an option to
  use ‘unified’ toolbars and titlebars.

  2. Setting the NSAppearance theme.

After messing about with NSAppearance I’ve discovered this is the
solution to one of my bugbears: if you set it to dark then the
scrollbars are no longer white, which always looks stupid with a dark
Emacs theme.

I’m not sure how these settings should be implemented, though. I think
they’d be best as frame parameters, but none of the existing frame
parameters are system dependent like these, so I don’t know if doing
it that way would upset anyone.

Alternatively we just make them variables which affect any
subsequently created frames.
-- 
Alan Third