From: Amos Bird <amosbird@gmail.com>
Date: Wed, 25 Apr 2018 20:41:09 +0800
Dear community,
I'm trying to setup one mode line per frame. Here is what I've
done.
1. turn on the head line of mini window by tweaking
window_wants_header_line.
2. change shrink_mini_window so that it shrinks mini window to
two
lines instead of one.
3. (setq-default header-line-format mode-line-format)
It's great to hear someone hacks the display code to add
features.
However, these issues are best discussed on emacs-devel, not
here.
Who knows, we could even ask you to contribute the code ;-)
However the header line doesn't get updated at all. It seems
xdisp.c only provides ways to update mode line, and I've
reached
the limit of my emacs-fu. How can I achieve this without
hacking
tons of the display logic? Many thanks!
I think you need to modify window_wants_header_line, it
currently has
hard-wired knowledge that a minibuffer window will never display
a
header line.
Once that is done, the feature should work, because the same
triggers
that update the mode line also update the header line, so this:
It seems xdisp.c only provides ways to update mode line
is inaccurate. See the part of redisplay_window immediately
following
the 'done' label: it calls display_mode_lines, which displays
both the
mode line and the header line.