[solved] Can anyone use gtk inspector and tell me the class name of the sidebar of gtk4 apps like nautilus
Basically I am using this gtk.css file in ~/.config/gtk-4.0/gtk.css but it's weird that the sidebar is not themed correctly. If anyone knows about this, please do tell. My only lead at this moment is to find the class and add it in gtk.css file. For some reason I can't install the gtk inspector app, So if anyone has it already or knows the classname, please help.
GTK Inspector comes with GTK, you don't need to install it.
Enable it with gsettings
gsettings get org.gtk.Settings.Debug enable-inspector-keybinding true
so you can invoke it either by running GTK_DEBUG=interactive application-name-here or, when alredy using the application, via Control + Shift + I/Control + Shift + D
I wanted to add on this, for anyone else stumbling across this post and struggling with sidebar theming: The above will work 90% of the time, but in case your some-random-theme.css overrides @sidebar_, or doesn't follow the naming convention to begin with, search your gtk.css for .sidebar-pane, which should be the actual css selector for @sidebar_, and .content-pane for @secondary-sidebar_.
Gotcha. One last thing. Do I need to define helper colors as well? currently I am not doing that, but it is defined in the adw styleguide. Ain't no way gruvbox has that much color varieties so what's your suggestion?
Nah, unless you're unhappy with the current outcome, you can leave it as it is.
Changes in .config/gtk-4.0/gtk.css will be applied on top of the stylesheet, so whatever you don't override there, will fall back to the default, that's why your sidebar previously went full Adwaita light mode.
After taking a brief look at the libadwaita source, as far as I can see, helper colors are a special case anyways, @borders as well as border_coloris used exclusively in the scssfiles (which the gtk.css is generated from), whereas the gtk.css for some reason doesn't get back to the generic name, but uses the assigned value alpha(currentColor,0.15) - which doesn't help your case at all.
To actually change @borders, you would need to modify its value in .scss and regenerate the .css then.
For your other point, there's no need to introduce a new color for this, since the helper color is an alpha value derived from your foreground color (that's what currentColor is referring to), so if you change _fg_color in gtk.css, @borders will change along with it.