How do you change the background color for only one window?

Question

I have tried ownsyntax but that does not work. I want do change the background color for only one window? I have tried this but it highlights all the windows.

hi Normal guibg=grey guifg=black

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It looks like it is wincolor, not sure if there's another way to change without adding a group. Not sure why my answer of wincolor was deleted.

I am working on an Rgb colors plugin in which I need to be able to look at the random colors. I accomplish by using a popup window with wincolor which seems to to work fine. The colors are not fixed, I just used this dictionary to show as an example. If there are better solutions than mine I would appreciate a response.

let color_keys = keys(s:css_colors)
for index in range(0,len(color_keys) - 1 )
    let color = color_keys[index]
    let popid= Popup(color,60000, index * 4)
    let cmd = 'hi TEMPCOLOR' . color . ' guibg='.color.' | let &wincolor="TEMPCOLOR'. color. '"'
    call win_execute(popid,cmd)
endfor

Here is an example of one buffer in one color and another buffer in another color.

Answer 1

1. The answer is different for Vim and Neovim. Vim has :h 'wincolor' to overwrite "Normal" for a given window, while Neovim has :h 'winhighlight' to override any number of highlighting groups.

2. You can't really assign arbitary colors to anything except a highlighting group. But you're not obliged to create new groups if existing ones are okay. For example, setlocal wincolor=PMenu is quite possible.

3. Syntax elements are essentially regexes. While "Normal" highlight is something used outside of all possible syntax matches. Sort of default. So even if one can build a regex to cover "Normal" highlight, it doesn't seem like a good idea.

4. :hi command is always global. :ownsyntax allows for a window to have own set of syntax elements, i.e. regexes. But once all groups are matched, their attributes are taken from the global table (except item (1)).

Answer 2

let color_keys = keys(s:css_colors)
for index in range(0,len(color_keys) - 1 )
    let color = color_keys[index]
    let popid= Popup(color,60000, index * 4)
    let cmd = 'hi TEMPCOLOR' . color . ' guibg='.color.' | let &wincolor="TEMPCOLOR'. color. '"'
    call win_execute(popid,cmd)
endfor