How can I use a different theme (or color scheme) for files in a specific directory?
Currently in my system, a single theme is applied to all buffers. The theme is chosen in ~/.emacs as
(load-theme 'zenburn t) I would like to use this theme by default, but I would like to use a different one when I visited a file in the specific directory. When I switch to a buffer not associated with a file in this directory, I would like the theme to go back to the default.
Generally, if you want to call some function on opening a buffer from some specific directory, then you can use .dir-locals.el, e.g. you could use the following definitions:
((nil . ((eval (lambda () (load-theme 'zenburn t))) (eval (lambda () (add-hook 'kill-buffer-hook (lambda () (disable-theme 'zenburn)) nil t)))))) However, this switches the theme only on creating or killing the buffer.
Therefore, to make it load/disable a theme on switching to/from the buffer you could use the following (hook-)function:
(defun conditionally-switch-theme () (when buffer-file-name (if (string= (file-name-directory buffer-file-name) "/your/directory/path") (load-theme 'zenburn t) (disable-theme 'zenburn)))) (add-hook 'window-configuration-change-hook #'conditionally-switch-theme) Finally, loading a theme does not disable the currently enabled themes. But as that is often not really necessary, I did not bother to sort it out. But if some things are not working as expected, then add some logic to remember the current custom-enabled-themes, disable them before loading the 'local' theme on entering the buffer, and enable the themes in the stored value of the previous custom-enabled-themes after disabling the 'local' theme when leaving the buffer (see also Custom themes in the Emacs manual).
window-configuration-change-hook isn't perfect, but I think it does do the job well enough. I am not sure which hook could be used better otherwise, e.g. I think pre/post-command-hook is too 'aggressive'. Anyway, you have a good start now to investigate further the available options, (incl. e.g. adding logic).