Re: Question about minibuffer and child frames (Posframe)

[Feng Shu]

Gerd Möllmann <gerd.moellmann@gmail.com> writes:

>> in posframe, cursor just a space with face of cursor.
>
> So Po Lu was remembering right!
>
> Do you perhaps know where that is done? I can't find it.
>
> Because it's definitely not working on ttys ATM. I mean the cursor in
> the parent frame's minibuffer doesn't bother me too much. But I would
> love it if something like a cursor appeared on the posframe.

Sorry, I remeber wrong, in vertico-posframe, we use real cursor, see
cursor-type in below function.

(defun vertico-posframe--show (buffer window-point)
  "`posframe-show' of vertico-posframe.

BUFFER will be showed by `posframe-show'.  After `posframe-show'
is called, window-point will be set to WINDOW-POINT."
  (let ((posframe
         ;; Some posframe poshandlers need infos of last-window.
         (with-selected-window (vertico-posframe-last-window)
           (apply #'posframe-show
                  buffer

                  ...

                  (funcall (buffer-local-value 'vertico-posframe-size-function 
buffer) buffer)))))
    ;; NOTE: `posframe-show' will force set window-point to 0, so we
    ;; need reset it again after `posframe-show'.
    (when (numberp window-point)
      (let ((window (frame-root-window posframe)))
        (when (window-live-p window)
          (set-window-point window window-point))))
    ;; NOTE: posframe will hide cursor, so we need let it show again.
    (with-current-buffer buffer
      (setq-local cursor-type t)
      (setq-local cursor-in-non-selected-windows 'box))))


But in ivy-posframe, we use space emular cursor instead:

(defun ivy-posframe--add-prompt (fn &rest args)
  "Add the ivy prompt to the posframe.  Advice FN with ARGS."
  (apply fn args)
  (when (and (display-graphic-p)
             (not ivy-posframe--ignore-prompt))
    (with-current-buffer (window-buffer (active-minibuffer-window))
      (let ((point (point))
            (prompt (buffer-string)))
        (remove-text-properties 0 (length prompt) '(read-only nil) prompt)
        (with-current-buffer ivy-posframe-buffer
          (goto-char (point-min))
          (delete-region (point) (line-beginning-position 2))
          (insert prompt "  \n")
          (add-text-properties point (1+ point) '(face ivy-posframe-cursor))))))


>
>>> frame's minibuffer this time contains the prompt and the cursor, too.
>>
>> Maybe the below hack is not work well in tty
>>
>>    (set-window-vscroll minibuffer-window 100)
>
> Yes, that's it. It's a no-op on terminals. 
>
>> In my opinion, hide minibuffer's content just hack way, I can not find a
>> better way to hide minibuffer window's content.
>
> Well, nobody could forsee that there would ever be child frames on tty
> ;-). 

Yes, I have tried many way to hide minibuffer's content, for example:
creating a new posframe to mask minibuffer window, let minibuffer
forecolor = backgroundcolor, but vscroll way is most stable, vertico's
author tell me this way:


>
> P.S.:
>
> As an aside, because that might affect Posframe maybe in the future. I
> also implemented borders around child frames now, but in a strange way,
> with the 'undecorated' frame parameter. If a tty child frame is not
> undecorated, a border is drawn around it, otherwise it isn't.
>
> The reason for this strange way of doing things is that I quit in a rage
> when trying to add the normal border handling for tty frames. Works for
> me. Just mentioning it so that others can comment how terrible that is
> :-).

OK, border setting in posframe is not simple, by the way, how to handle
border width in tty?

------------------------------------------------------------------

By default, posframe shows no borders, but users can specify
borders by setting BORDER-WIDTH to a positive number.  Border
color can be specified by BORDER-COLOR.

INTERNAL-BORDER-WIDTH and INTERNAL-BORDER-COLOR are same as
BORDER-WIDTH and BORDER-COLOR, but do not suggest to use for the
reason:

   Add distinct controls for child frames' borders (Bug#45620)
   
http://git.savannah.gnu.org/cgit/emacs.git/commit/?id=ff7b1a133bfa7f2614650f8551824ffaef13fadc






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