just-the-text Emacs frame (was: Emacs as a desktop environment)

[Ted Zlatanov]

I just want to display some text, nothing else.  How about this (based
on your code) to show some arbitrary text in a popup (no menus,
modeline, etc., just the buffer is visible)?  I think it will DTRT
whether the frame is shown already or not.  I can use this to show the
indicators, icons, and status messages.

#+begin_src lisp
(require 'battery)
(require 'timeclock)

(defvar popup-info-frame)

(defun popup-info-string ()
  (format "%s\n%s\n%s\n%s"
          (format-time-string "%H:%M %Y-%m-%d" (current-time))
          (battery-format battery-echo-area-format (funcall
                                                    battery-status-function))
          (timeclock-status-string)
          (shell-command-to-string "nmcli -p dev")))

(defun popup-info ()
  (interactive)
  (popup-info--1 " *popup status*"))

(defun popup-info--1 (bufname)
  (with-current-buffer (get-buffer-create bufname)
    (make-local-variable 'popup-info-frame)
    (if (and (boundp 'popup-info-frame)
             popup-info-frame
             (member popup-info-frame (frame-list)))
        (select-frame popup-info-frame)
      (let ((default-frame-alist '((minibuffer . nil)
                                   (width . 20)
                                   (border-width . 0)
                                   (menu-bar-lines . 0)
                                   (tool-bar-lines . 0)
                                   (unsplittable . t)
                                   (left-fringe . 0))))
        (switch-to-buffer-other-frame bufname)
        (setq popup-info-frame (selected-frame))))
    (erase-buffer)
    (setq mode-line-format nil)
    (redraw-modeline)
    (insert (popup-info-string))))

#+end_src

Let me know what you think.  It supports any number of status buffers by
name and behaves correctly even if the frame is closed.

Thanks!
Ted