1
0
mirror of https://git.savannah.gnu.org/git/emacs.git synced 2024-11-21 06:55:39 +00:00
emacs/lisp/scroll-all.el
2024-01-02 09:47:10 +08:00

121 lines
4.1 KiB
EmacsLisp

;;; scroll-all.el --- scroll all buffers together minor mode -*- lexical-binding: t -*-
;; Copyright (C) 1997, 2001-2024 Free Software Foundation, Inc.
;; Author: Gary D. Foster <Gary.Foster@corp.sun.com>
;; Keywords: convenience scroll lock
;; This file is part of GNU Emacs.
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; This mode allows multiple buffers to be 'locked' so that scrolling
;; up or down lines in any buffer causes all the buffers to mirror
;; the scrolling. It hooks into the post-command-hook to check for
;; potential scrolling commands and if we're locked, mirrors them in all
;; windows. This allows us to grab line-at-a-time scrolling as well as
;; screen-at-a-time scrolling, and doesn't remap any of the keyboard
;; commands to do it.
;; You can enable and disable this mode with the 'scroll-all-mode' command.
;; Suggestions/ideas from:
;; Rick Macdonald <rickm@vsl.com>
;; Anders Lindgren
;;; Code:
(defun scroll-all-function-all (func arg)
"Apply function FUNC with argument ARG to all visible windows."
(let ((num-windows (count-windows))
(count 1))
(when (> num-windows 1)
(other-window 1)
(while (< count num-windows)
(condition-case nil
(funcall func arg)
;; Ignore beginning- or end-of-buffer error in other windows.
(error nil))
(other-window 1)
(setq count (1+ count))))))
(defun scroll-all-scroll-down-all (arg)
"Scroll down ARG lines in all visible windows."
(interactive "p")
(scroll-all-function-all 'next-line arg))
(defun scroll-all-scroll-up-all (arg)
"Scroll up ARG lines in all visible windows."
(interactive "p")
(scroll-all-function-all 'previous-line arg))
(defun scroll-all-page-down-all (arg)
"Page down in all visible windows.
ARG is like in `scroll-up'."
(interactive "P")
(scroll-all-function-all 'scroll-up arg))
(defun scroll-all-page-up-all (arg)
"Page up in all visible windows.
ARG is like in `scroll-down'."
(interactive "P")
(scroll-all-function-all 'scroll-down arg))
(defun scroll-all-beginning-of-buffer-all (arg)
"Go to the beginning of the buffer in all visible windows.
ARG is like in `beginning-of-buffer'."
(interactive "P")
(scroll-all-function-all 'beginning-of-buffer arg))
(defun scroll-all-end-of-buffer-all (arg)
"Go to the end of the buffer in all visible windows.
ARG is like in `end-of-buffer'."
(interactive "P")
(scroll-all-function-all 'end-of-buffer arg))
(defun scroll-all-check-to-scroll ()
"Check `this-command' to see if a scroll is to be done."
(cond ((eq this-command 'next-line)
(call-interactively 'scroll-all-scroll-down-all))
((eq this-command 'previous-line)
(call-interactively 'scroll-all-scroll-up-all))
((memq this-command '(scroll-up scroll-up-command))
(call-interactively 'scroll-all-page-down-all))
((memq this-command '(scroll-down scroll-down-command))
(call-interactively 'scroll-all-page-up-all))
((eq this-command 'beginning-of-buffer)
(call-interactively 'scroll-all-beginning-of-buffer-all))
((eq this-command 'end-of-buffer)
(call-interactively 'scroll-all-end-of-buffer-all))))
;;;###autoload
(define-minor-mode scroll-all-mode
"Toggle shared scrolling in same-frame windows (Scroll-All mode).
When Scroll-All mode is enabled, scrolling commands invoked in
one window apply to all visible windows in the same frame."
:lighter " *SL*"
:global t
:group 'windows
(if scroll-all-mode
(add-hook 'post-command-hook 'scroll-all-check-to-scroll)
(remove-hook 'post-command-hook 'scroll-all-check-to-scroll)))
(provide 'scroll-all)
;;; scroll-all.el ends here