No defaults, menubar.xml *probably* false hope
I spent a few hours getting acquainted with the System folder in Leopard when I first got it. One of the things I tried to do was disable the transparency on the menubar. I was not successful. Here's a list of things that were mentioned above and elsewhere and their effect:
Trick: Put a white/black rectangle on the top of background images to "disable" the transparent effect.
Result: This is the *best* way I know of so far to get rid of it. It works very well but takes a lot of effort to do especially if you like to change backgrounds a lot. It has to be something like 21pixels tall in a native screen resolution image. Black gives it a more grey Leopard-like look, white of course is much brighter and looks more like the Tiger menubar.
Trick: Find the defaults setting for the menubar and disable it, like the no_glass setting for the dock.
Result: After a thorough search of the defaults and domains, there is no such setting even related to the menubar. The closest thing in there is SystemUI and Menuclock domains, and they don't affect transparency. (To get a list of domains, type "defaults domains > ~/Desktop/defaults_domains.txt". Use "defaults read > ~/Desktop/defaults_read.txt" to get the whole thing)
Trick: Edit the menubar.xml file in /System/Library/PrivateFrameworks/CoreUI.framework/Versions/A/Resources/LeopardUI.bundle->Contents/Recipes
Result: This framework is apparently supposed to deal with resolution independence and how to draw certain elements at different scales [see
http://arstechnica.com/reviews/os/mac-os-x-10-5.ars/10]. Playing with the setting did not affect the menubar in any noticeable way in my experiments.
Trick: Use Quartz Debug [Spotlight it] to disable Quartz Extreme, and Voila, no more transparent menubar. (Screen shots below)
Result: Voila, the rest of the system struggles with effect like minimizing windows. This solution is only useful to show a connection between the two features and to preview the bar as opaque, but does not solve anything.
Trick: Just keep reinstalling the OS until the bar is Opaque for no clear reason.
Result: Of course this is a joke. Some people have been getting an opaque bar on the same machines others have been getting transparent bars. This seems to indicate a flaw in the way the OS determines whether to enable the feature.
Those are the only techniques I've seen attempted so far. My guess is the opacity is coded in somewhere rather than a config file setting (maybe as a last-minute hack to get it out the door as speculated in prior posts). One thing is for sure though: there are a lot of people who do not like the feature and would like a way to disable it. It's not like Apple to "fix" something that's not broken, so a way to disable it may not ever be provided by them. On the other hand, I don't think it would be that unlikely to include a tick box for the setting somewhere in 10.5.x either, I'm just not holding my breath. Somebody will create a clever hack soon though no doubt.
