\f
;;;; Helpful functions for enabling and disabling scroll bars.
-(defun set-scroll-bar-mode (ignore value)
+(defvar scroll-bar-mode)
+
+(defvar scroll-bar-mode-explicit nil
+ "Non-nil means `set-scroll-bar-mode' should really do something.
+This is nil while loading `scroll-bar.el', and t afterward.")
+
+(defun set-scroll-bar-mode-1 (ignore value)
+ (set-scroll-bar-mode value))
+
+(defun set-scroll-bar-mode (value)
"Set `scroll-bar-mode' to VALUE and put the new value into effect."
(setq scroll-bar-mode value)
- ;; Apply it to default-frame-alist.
- (let ((parameter (assq 'vertical-scroll-bars default-frame-alist)))
- (if (consp parameter)
- (setcdr parameter scroll-bar-mode)
- (setq default-frame-alist
- (cons (cons 'vertical-scroll-bars scroll-bar-mode)
- default-frame-alist))))
-
- ;; Apply it to existing frames.
- (let ((frames (frame-list)))
- (while frames
- (modify-frame-parameters
- (car frames)
- (list (cons 'vertical-scroll-bars scroll-bar-mode)))
- (setq frames (cdr frames)))))
-
-(defcustom scroll-bar-mode 'left
+ (when scroll-bar-mode-explicit
+ ;; Apply it to default-frame-alist.
+ (let ((parameter (assq 'vertical-scroll-bars default-frame-alist)))
+ (if (consp parameter)
+ (setcdr parameter scroll-bar-mode)
+ (setq default-frame-alist
+ (cons (cons 'vertical-scroll-bars scroll-bar-mode)
+ default-frame-alist))))
+
+ ;; Apply it to existing frames.
+ (let ((frames (frame-list)))
+ (while frames
+ (modify-frame-parameters
+ (car frames)
+ (list (cons 'vertical-scroll-bars scroll-bar-mode)))
+ (setq frames (cdr frames))))))
+
+(defcustom scroll-bar-mode
+ (if (eq system-type 'windows-nt) 'right 'left)
"*Specify whether to have vertical scroll bars, and on which side.
Possible values are nil (no scroll bars), `left' (scroll bars on left)
and `right' (scroll bars on right).
-When you set the variable in a Lisp program, it takes effect for new frames,
-and for existing frames when `toggle-scroll-bar' is used.
-When you set this with the customization buffer,
-it takes effect immediately for all frames."
+To set this variable in a Lisp program, use `set-scroll-bar-mode'
+to make it take real effect.
+Setting the variable with a customization buffer also takes effect."
:type '(choice (const :tag "none (nil)")
(const left)
(const right))
:group 'frames
- :set 'set-scroll-bar-mode)
+ :set 'set-scroll-bar-mode-1)
+
+;; We just set scroll-bar-mode, but that was the default.
+;; If it is set again, that is for real.
+(setq scroll-bar-mode-explicit t)
(defun scroll-bar-mode (flag)
"Toggle display of vertical scroll bars on all frames.
(if flag (setq flag (prefix-numeric-value flag)))
;; Tweedle the variable according to the argument.
- (set-scroll-bar-mode nil
- (if (null flag) (not scroll-bar-mode)
+ (set-scroll-bar-mode (if (null flag) (not scroll-bar-mode)
(and (or (not (numberp flag)) (>= flag 0))
- 'left))))
+ (if (eq system-type 'windows-nt) 'right 'left)))))
(defun toggle-scroll-bar (arg)
"Toggle whether or not the selected frame has vertical scroll bars.
(setq arg
(if (cdr (assq 'vertical-scroll-bars
(frame-parameters (selected-frame))))
- -1 1)))
- (modify-frame-parameters (selected-frame)
- (list (cons 'vertical-scroll-bars
- (if (> arg 0)
- (or scroll-bar-mode 'left))))))
+ -1 1))
+ (setq arg (prefix-numeric-value arg)))
+ (modify-frame-parameters
+ (selected-frame)
+ (list (cons 'vertical-scroll-bars
+ (if (> arg 0)
+ (or scroll-bar-mode
+ (if (eq system-type 'windows-nt) 'right 'left)))))))
(defun toggle-horizontal-scroll-bar (arg)
"Toggle whether or not the selected frame has horizontal scroll bars.
(setq next-portion-start (max
(scroll-bar-drag-position next-portion-whole)
(1+ portion-start)))
- (if (or (> current-start next-portion-start)
+ (if (or (>= current-start next-portion-start)
(< current-start portion-start))
(set-window-start window portion-start)
;; Always set window start, to ensure scroll bar position is updated.
If you click outside the slider, the window scrolls to bring the slider there."
(interactive "e")
(let* (done
- (echo-keystrokes 0))
- (or point-before-scroll
- (setq point-before-scroll (point)))
- ;; Our scrolling can move point; don't let that clear point-before-scroll.
- (let (point-before-scroll)
- (scroll-bar-drag-1 event)
- (track-mouse
- (while (not done)
- (setq event (read-event))
- (if (eq (car-safe event) 'mouse-movement)
- (setq event (read-event)))
- (cond ((eq (car-safe event) 'scroll-bar-movement)
- (scroll-bar-drag-1 event))
- (t
- ;; Exit when we get the drag event; ignore that event.
- (setq done t)))))
- (sit-for 0))))
+ (echo-keystrokes 0)
+ (end-position (event-end event))
+ (window (nth 0 end-position))
+ (before-scroll))
+ (with-current-buffer (window-buffer window)
+ (setq before-scroll point-before-scroll))
+ (save-selected-window
+ (select-window window)
+ (setq before-scroll
+ (or before-scroll (point))))
+ (scroll-bar-drag-1 event)
+ (track-mouse
+ (while (not done)
+ (setq event (read-event))
+ (if (eq (car-safe event) 'mouse-movement)
+ (setq event (read-event)))
+ (cond ((eq (car-safe event) 'scroll-bar-movement)
+ (scroll-bar-drag-1 event))
+ (t
+ ;; Exit when we get the drag event; ignore that event.
+ (setq done t)))))
+ (sit-for 0)
+ (with-current-buffer (window-buffer window)
+ (setq point-before-scroll before-scroll))))
(defun scroll-bar-scroll-down (event)
"Scroll the window's top line down to the location of the scroll bar click.
EVENT should be a scroll bar click."
(interactive "e")
- (let ((old-selected-window (selected-window)))
+ (let* ((end-position (event-end event))
+ (window (nth 0 end-position))
+ (before-scroll))
+ (with-current-buffer (window-buffer window)
+ (setq before-scroll point-before-scroll))
(unwind-protect
- (progn
- (let* ((end-position (event-end event))
- (window (nth 0 end-position))
- (portion-whole (nth 2 end-position)))
- (let (point-before-scroll)
- (select-window window))
- (or point-before-scroll
- (setq point-before-scroll (point)))
- (let (point-before-scroll)
- (scroll-down
- (scroll-bar-scale portion-whole (1- (window-height)))))))
- (select-window old-selected-window))))
+ (save-selected-window
+ (let ((portion-whole (nth 2 end-position)))
+ (select-window window)
+ (setq before-scroll
+ (or before-scroll (point)))
+ (scroll-down
+ (scroll-bar-scale portion-whole (1- (window-height)))))
+ (sit-for 0))
+ (with-current-buffer (window-buffer window)
+ (setq point-before-scroll before-scroll)))))
(defun scroll-bar-scroll-up (event)
"Scroll the line next to the scroll bar click to the top of the window.
EVENT should be a scroll bar click."
(interactive "e")
- (let ((old-selected-window (selected-window)))
+ (let* ((end-position (event-end event))
+ (window (nth 0 end-position))
+ (before-scroll))
+ (with-current-buffer (window-buffer window)
+ (setq before-scroll point-before-scroll))
(unwind-protect
- (progn
- (let* ((end-position (event-end event))
- (window (nth 0 end-position))
- (portion-whole (nth 2 end-position)))
- (let (point-before-scroll)
- (select-window window))
- (or point-before-scroll
- (setq point-before-scroll (point)))
- (let (point-before-scroll)
- (scroll-up
- (scroll-bar-scale portion-whole (1- (window-height)))))))
- (select-window old-selected-window))))
+ (save-selected-window
+ (let ((portion-whole (nth 2 end-position)))
+ (select-window window)
+ (setq before-scroll
+ (or before-scroll (point)))
+ (scroll-up
+ (scroll-bar-scale portion-whole (1- (window-height)))))
+ (sit-for 0))
+ (with-current-buffer (window-buffer window)
+ (setq point-before-scroll before-scroll)))))
\f
-;;;; Bindings.
+;;; Tookit scroll bars.
-;;; For now, we'll set things up to work like xterm.
-(global-set-key [vertical-scroll-bar mouse-1] 'scroll-bar-scroll-up)
-(global-set-key [vertical-scroll-bar drag-mouse-1] 'scroll-bar-scroll-up)
+(defun scroll-bar-toolkit-scroll (event)
+ (interactive "e")
+ (let* ((end-position (event-end event))
+ (window (nth 0 end-position))
+ (part (nth 4 end-position))
+ before-scroll)
+ (cond ((eq part 'end-scroll))
+ (t
+ (with-current-buffer (window-buffer window)
+ (setq before-scroll point-before-scroll))
+ (save-selected-window
+ (select-window window)
+ (setq before-scroll (or before-scroll (point)))
+ (cond ((eq part 'above-handle)
+ (scroll-up '-))
+ ((eq part 'below-handle)
+ (scroll-up nil))
+ ((eq part 'ratio)
+ (let* ((portion-whole (nth 2 end-position))
+ (lines (scroll-bar-scale portion-whole
+ (1- (window-height)))))
+ (scroll-up (cond ((not (zerop lines)) lines)
+ ((< (car portion-whole) 0) -1)
+ (t 1)))))
+ ((eq part 'up)
+ (scroll-up -1))
+ ((eq part 'down)
+ (scroll-up 1))
+ ((eq part 'top)
+ (set-window-start window (point-min)))
+ ((eq part 'bottom)
+ (goto-char (point-max))
+ (recenter))
+ ((eq part 'handle)
+ (scroll-bar-drag-1 event))))
+ (sit-for 0)
+ (with-current-buffer (window-buffer window)
+ (setq point-before-scroll before-scroll))))))
-(global-set-key [vertical-scroll-bar down-mouse-2] 'scroll-bar-drag)
-(global-set-key [vertical-scroll-bar mouse-3] 'scroll-bar-scroll-down)
-(global-set-key [vertical-scroll-bar drag-mouse-3] 'scroll-bar-scroll-down)
+\f
+;;;; Bindings.
+
+;;; For now, we'll set things up to work like xterm.
+(cond (x-toolkit-scroll-bars-p
+ (global-set-key [vertical-scroll-bar mouse-1]
+ 'scroll-bar-toolkit-scroll))
+ (t
+ (global-set-key [vertical-scroll-bar mouse-1]
+ 'scroll-bar-scroll-up)
+ (global-set-key [vertical-scroll-bar drag-mouse-1]
+ 'scroll-bar-scroll-up)
+ (global-set-key [vertical-scroll-bar down-mouse-2]
+ 'scroll-bar-drag)
+ (global-set-key [vertical-scroll-bar mouse-3]
+ 'scroll-bar-scroll-down)
+ (global-set-key [vertical-scroll-bar drag-mouse-3]
+ 'scroll-bar-scroll-down)))
\f
(provide 'scroll-bar)