special face for marks (was: setting face in gnus-user-format-function-x)

[pmlists@free.fr (Peter Münster)]

On Mon, May 30 2011, Lars Magne Ingebrigtsen wrote:

> pmlists@free.fr (Peter Münster) writes:
>
>> I would like to set different faces for some marks in the summary lines.
>> But unfortunately, when changing the mark, the mark-letter is updated,
>> but the face is not. Only after reopening the group, the faces get
>> right.
>
> I think your best bet would be to put a function into
> `gnus-summary-update-hook', possibly calling
> `gnus-summary-update-article-line' to delete the line and reinsert it.

Unfortunately, there were too many side effects, when calling
gnus-summary-update-article-line:
- %P (line number) broken
- %B (thread symbols) vanished
- strange behaviour when dummy-lines are present
- perhaps more...

But today I've found a solution, that works quite well. Perhaps you
could add something like that to Gnus.
My motivation: various faces for different states are nice, but when the
faces are set for the whole lines, it can disturb the eyes. Setting the
face just for the mark can look better. Pine/Alpine does it like that,
and I liked it.

So, here the solution, that works for me:

--8<---------------cut here---------------start------------->8---
(setq gnus-summary-highlight-mark
      '(gnus-ticked-mark        gnus-ticked-mark-face
        gnus-unseen-mark        gnus-new-mark-face
        gnus-unread-mark        gnus-new-mark-face
        gnus-read-mark          gnus-read-mark-face
        gnus-killed-mark        gnus-del-mark-face
        gnus-expirable-mark     gnus-del-mark-face
        gnus-replied-mark       gnus-replied-mark-face
        gnus-forwarded-mark     gnus-replied-mark-face
        gnus-recent-mark        gnus-new-mark-face
        gnus-ancient-mark       gnus-read-mark-face
        gnus-dormant-mark       gnus-ticked-mark-face))

(defun my-mark-face (chr)
  (let ((face 'gnus-unknown-mark-face)
        (list gnus-summary-highlight-mark))
    (while list
      (if (equal (symbol-value (car list)) chr)
          (setq face (cadr list)
                list nil)
        (setq list (cddr list))))
    face))

(defun my-summary-update ()
  (save-excursion
    (beginning-of-line) ; because here is the mark!
    (let* ((inhibit-read-only t)
           (pt (point))
           (chr (char-after pt)))
      (put-text-property pt (1+ pt)
                         'face (my-mark-face chr)))))

(add-hook 'gnus-summary-update-hook 'my-summary-update)
--8<---------------cut here---------------end--------------->8---

-- 
           Peter