diff options
Diffstat (limited to 'lisp/window.el')
| -rw-r--r-- | lisp/window.el | 157 |
1 files changed, 146 insertions, 11 deletions
diff --git a/lisp/window.el b/lisp/window.el index c5a1019372c..ce0256f1fff 100644 --- a/lisp/window.el +++ b/lisp/window.el @@ -28,17 +28,6 @@ ;;; Code: -(defvar selected-window-group-function nil) -(make-variable-buffer-local 'selected-window-group-function) -(put 'selected-window-group-function 'permanent-local t) -(defun selected-window-group () - "Return the list of windows in the group containing the selected window. -When a grouping mode (such as Follow Mode) is not active, the -result is a list containing only the selected window." - (if (functionp selected-window-group-function) - (funcall selected-window-group-function) - (list (selected-window)))) - (defun internal--before-save-selected-window () (cons (selected-window) ;; We save and restore all frames' selected windows, because @@ -7881,6 +7870,152 @@ Return non-nil if the window was shrunk, nil otherwise." (remove-hook 'kill-buffer-hook delete-window-hook t)))))) +;;; +;; Groups of windows (Follow Mode). +;; +;; This section of functions extends the functionality of some window +;; manipulating commands to groups of windows co-operatively +;; displaying a buffer, typically with Follow Mode. +;; +;; The xxx-function variables are permanent locals so that their local +;; status is undone only when explicitly programmed, not when a buffer +;; is reverted or a mode function is called. + +(defvar window-group-start-function nil) +(make-variable-buffer-local 'window-group-start-function) +(put 'window-group-start-function 'permanent-local t) +(defun window-group-start (&optional window) + "Return position at which display currently starts in the group of +windows containing WINDOW. When a grouping mode (such as Follow Mode) +is not active, this function is identical to `window-start'. + +WINDOW must be a live window and defaults to the selected one. +This is updated by redisplay or by calling `set-window*-start'." + (if (functionp window-group-start-function) + (funcall window-group-start-function window) + (window-start window))) + +(defvar window-group-end-function nil) +(make-variable-buffer-local 'window-group-end-function) +(put 'window-group-end-function 'permanent-local t) +(defun window-group-end (&optional window update) + "Return position at which display currently ends in the group of +windows containing WINDOW. When a grouping mode (such as Follow Mode) +is not active, this function is identical to `window-end'. + +WINDOW must be a live window and defaults to the selected one. +This is updated by redisplay, when it runs to completion. +Simply changing the buffer text or setting `window-group-start' +does not update this value. +Return nil if there is no recorded value. (This can happen if the +last redisplay of WINDOW was preempted, and did not finish.) +If UPDATE is non-nil, compute the up-to-date position +if it isn't already recorded." + (if (functionp window-group-end-function) + (funcall window-group-end-function window update) + (window-end window update))) + +(defvar set-window-group-start-function nil) +(make-variable-buffer-local 'set-window-group-start-function) +(put 'set-window-group-start-function 'permanent-local t) +(defun set-window-group-start (window pos &optional noforce) + "Make display in the group of windows containing WINDOW start at +position POS in WINDOW's buffer. When a grouping mode (such as Follow +Mode) is not active, this function is identical to `set-window-start'. + +WINDOW must be a live window and defaults to the selected one. Return +POS. Optional third arg NOFORCE non-nil inhibits next redisplay from +overriding motion of point in order to display at this exact start." + (if (functionp set-window-group-start-function) + (funcall set-window-group-start-function window pos noforce) + (set-window-start window pos noforce))) + +(defvar recenter-group-function nil) +(make-variable-buffer-local 'recenter-group-function) +(put 'recenter-group-function 'permanent-local t) +(defun recenter-group (&optional arg) + "Center point in the group of windows containing the selected window +and maybe redisplay frame. When a grouping mode (such as Follow Mode) +is not active, this function is identical to `recenter'. + +With a numeric prefix argument ARG, recenter putting point on screen line ARG +relative to the first window in the selected window group. If ARG is +negative, it counts up from the bottom of the last window in the +group. (ARG should be less than the total height of the window group.) + +If ARG is omitted or nil, then recenter with point on the middle line of +the selected window group; if the variable `recenter-redisplay' is +non-nil, also erase the entire frame and redraw it (when +`auto-resize-tool-bars' is set to `grow-only', this resets the +tool-bar's height to the minimum height needed); if +`recenter-redisplay' has the special value `tty', then only tty frames +are redrawn. + +Just C-u as prefix means put point in the center of the window +and redisplay normally--don't erase and redraw the frame." + (if (functionp recenter-group-function) + (funcall recenter-group-function arg) + (recenter arg))) + +(defvar pos-visible-in-window-group-p-function nil) +(make-variable-buffer-local 'pos-visible-in-window-group-p-function) +(put 'pos-visible-in-window-group-p-function 'permanent-local t) +(defun pos-visible-in-window-group-p (&optional pos window partially) + "Return non-nil if position POS is currently on the frame in the +window group containing WINDOW. When a grouping mode (such as Follow +Mode) is not active, this function is identical to +`pos-visible-in-window-p'. + +WINDOW must be a live window and defaults to the selected one. + +Return nil if that position is scrolled vertically out of view. If a +character is only partially visible, nil is returned, unless the +optional argument PARTIALLY is non-nil. If POS is only out of view +because of horizontal scrolling, return non-nil. If POS is t, it +specifies the position of the last visible glyph in the window group. +POS defaults to point in WINDOW; WINDOW defaults to the selected +window. + +If POS is visible, return t if PARTIALLY is nil; if PARTIALLY is non-nil, +the return value is a list of 2 or 6 elements (X Y [RTOP RBOT ROWH VPOS]), +where X and Y are the pixel coordinates relative to the top left corner +of the window. The remaining elements are omitted if the character after +POS is fully visible; otherwise, RTOP and RBOT are the number of pixels +off-window at the top and bottom of the screen line (\"row\") containing +POS, ROWH is the visible height of that row, and VPOS is the row number +\(zero-based)." + (if (functionp pos-visible-in-window-group-p-function) + (funcall pos-visible-in-window-group-p-function pos window partially) + (pos-visible-in-window-p pos window partially))) + +(defvar selected-window-group-function nil) +(make-variable-buffer-local 'selected-window-group-function) +(put 'selected-window-group-function 'permanent-local t) +(defun selected-window-group () + "Return the list of windows in the group containing the selected window. +When a grouping mode (such as Follow Mode) is not active, the +result is a list containing only the selected window." + (if (functionp selected-window-group-function) + (funcall selected-window-group-function) + (list (selected-window)))) + +(defvar move-to-window-group-line-function nil) +(make-variable-buffer-local 'move-to-window-group-line-function) +(put 'move-to-window-group-line-function 'permanent-local t) +(defun move-to-window-group-line (arg) + "Position point relative to the the current group of windows. +When a grouping mode (such as Follow Mode) is not active, this +function is identical to `move-to-window-line'. + +ARG nil means position point at center of the window group. +Else, ARG specifies the vertical position within the window +group; zero means top of first window in the group, negative +means relative to the bottom of the last window in the group." + (if (functionp move-to-window-group-line-function) + (funcall move-to-window-group-line-function arg) + (move-to-window-line arg))) + + (defvar recenter-last-op nil "Indicates the last recenter operation performed. Possible values: `top', `middle', `bottom', integer or float numbers. |