1;;; fringe.el --- fringe setup and control 2 3;; Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. 4 5;; Author: Simon Josefsson <simon@josefsson.org> 6;; Maintainer: FSF 7;; Keywords: frames 8 9;; This file is part of GNU Emacs. 10 11;; GNU Emacs is free software; you can redistribute it and/or modify 12;; it under the terms of the GNU General Public License as published by 13;; the Free Software Foundation; either version 2, or (at your option) 14;; any later version. 15 16;; GNU Emacs is distributed in the hope that it will be useful, 17;; but WITHOUT ANY WARRANTY; without even the implied warranty of 18;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19;; GNU General Public License for more details. 20 21;; You should have received a copy of the GNU General Public License 22;; along with GNU Emacs; see the file COPYING. If not, write to the 23;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 24;; Boston, MA 02110-1301, USA. 25 26;;; Commentary: 27 28;; This file contains code to initialize the built-in fringe bitmaps 29;; as well as helpful functions for customizing the appearance of the 30;; fringe. 31 32;; The code is influenced by scroll-bar.el and avoid.el. The author 33;; gratefully acknowledge comments and suggestions made by Miles 34;; Bader, Eli Zaretski, Richard Stallman, Pavel Janík and others which 35;; improved this package. 36 37;;; Code: 38 39(defgroup fringe nil 40 "Window fringes." 41 :version "22.1" 42 :group 'frames) 43 44;; Define the built-in fringe bitmaps and setup default mappings 45 46(when (boundp 'fringe-bitmaps) 47 (let ((bitmaps '(question-mark 48 left-arrow right-arrow up-arrow down-arrow 49 left-curly-arrow right-curly-arrow 50 left-triangle right-triangle 51 top-left-angle top-right-angle 52 bottom-left-angle bottom-right-angle 53 left-bracket right-bracket 54 filled-rectangle hollow-rectangle 55 filled-square hollow-square 56 vertical-bar horizontal-bar 57 empty-line)) 58 (bn 1)) 59 (while bitmaps 60 (push (car bitmaps) fringe-bitmaps) 61 (put (car bitmaps) 'fringe bn) 62 (setq bitmaps (cdr bitmaps) 63 bn (1+ bn)))) 64 65 (setq-default fringe-indicator-alist 66 '((truncation . (left-arrow right-arrow)) 67 (continuation . (left-curly-arrow right-curly-arrow)) 68 (overlay-arrow . right-triangle) 69 (up . up-arrow) 70 (down . down-arrow) 71 (top . (top-left-angle top-right-angle)) 72 (bottom . (bottom-left-angle bottom-right-angle 73 top-right-angle top-left-angle)) 74 (top-bottom . (left-bracket right-bracket 75 top-right-angle top-left-angle)) 76 (empty-line . empty-line) 77 (unknown . question-mark))) 78 79 (setq-default fringe-cursor-alist 80 '((box . filled-rectangle) 81 (hollow . hollow-rectangle) 82 (bar . vertical-bar) 83 (hbar . horizontal-bar) 84 (hollow-small . hollow-square)))) 85 86 87(defmacro fringe-bitmap-p (symbol) 88 "Return non-nil if SYMBOL is a fringe bitmap." 89 `(get ,symbol 'fringe)) 90 91 92;; Control presence of fringes 93 94(defvar fringe-mode) 95 96(defun set-fringe-mode-1 (ignore value) 97 "Call `set-fringe-mode' with VALUE. 98See `fringe-mode' for valid values and their effect. 99This is usually invoked when setting `fringe-mode' via customize." 100 (set-fringe-mode value)) 101 102(defun set-fringe-mode (value) 103 "Set `fringe-mode' to VALUE and put the new value into effect. 104See `fringe-mode' for possible values and their effect." 105 (setq fringe-mode value) 106 107 ;; Apply it to default-frame-alist. 108 (let ((parameter (assq 'left-fringe default-frame-alist))) 109 (if (consp parameter) 110 (setcdr parameter (if (consp fringe-mode) 111 (car fringe-mode) 112 fringe-mode)) 113 (setq default-frame-alist 114 (cons (cons 'left-fringe (if (consp fringe-mode) 115 (car fringe-mode) 116 fringe-mode)) 117 default-frame-alist)))) 118 (let ((parameter (assq 'right-fringe default-frame-alist))) 119 (if (consp parameter) 120 (setcdr parameter (if (consp fringe-mode) 121 (cdr fringe-mode) 122 fringe-mode)) 123 (setq default-frame-alist 124 (cons (cons 'right-fringe (if (consp fringe-mode) 125 (cdr fringe-mode) 126 fringe-mode)) 127 default-frame-alist)))) 128 129 ;; Apply it to existing frames. 130 (let ((frames (frame-list))) 131 (while frames 132 (modify-frame-parameters 133 (car frames) 134 (list (cons 'left-fringe (if (consp fringe-mode) 135 (car fringe-mode) 136 fringe-mode)) 137 (cons 'right-fringe (if (consp fringe-mode) 138 (cdr fringe-mode) 139 fringe-mode)))) 140 (setq frames (cdr frames))))) 141 142;; For initialization of fringe-mode, take account of changes 143;; made explicitly to default-frame-alist. 144(defun fringe-mode-initialize (symbol value) 145 (let* ((left-pair (assq 'left-fringe default-frame-alist)) 146 (right-pair (assq 'right-fringe default-frame-alist)) 147 (left (cdr left-pair)) 148 (right (cdr right-pair))) 149 (if (or left-pair right-pair) 150 ;; If there's something in default-frame-alist for fringes, 151 ;; don't change it, but reflect that into the value of fringe-mode. 152 (progn 153 (setq fringe-mode (cons left right)) 154 (if (equal fringe-mode '(nil . nil)) 155 (setq fringe-mode nil)) 156 (if (equal fringe-mode '(0 . 0)) 157 (setq fringe-mode 0))) 158 ;; Otherwise impose the user-specified value of fringe-mode. 159 (custom-initialize-reset symbol value)))) 160 161(defcustom fringe-mode nil 162 "*Specify appearance of fringes on all frames. 163This variable can be nil (the default) meaning the fringes should have 164the default width (8 pixels), it can be an integer value specifying 165the width of both left and right fringe (where 0 means no fringe), or 166a cons cell where car indicates width of left fringe and cdr indicates 167width of right fringe (where again 0 can be used to indicate no 168fringe). 169To set this variable in a Lisp program, use `set-fringe-mode' to make 170it take real effect. 171Setting the variable with a customization buffer also takes effect. 172If you only want to modify the appearance of the fringe in one frame, 173you can use the interactive function `set-fringe-style'." 174 :type '(choice (const :tag "Default width" nil) 175 (const :tag "No fringes" 0) 176 (const :tag "Only right" (0 . nil)) 177 (const :tag "Only left" (nil . 0)) 178 (const :tag "Half width" (5 . 5)) 179 (const :tag "Minimal" (1 . 1)) 180 (integer :tag "Specific width") 181 (cons :tag "Different left/right sizes" 182 (integer :tag "Left width") 183 (integer :tag "Right width"))) 184 :group 'fringe 185 :require 'fringe 186 :initialize 'fringe-mode-initialize 187 :set 'set-fringe-mode-1) 188 189(defun fringe-query-style (&optional all-frames) 190 "Query user for fringe style. 191Returns values suitable for left-fringe and right-fringe frame parameters. 192If ALL-FRAMES, the negation of the fringe values in 193`default-frame-alist' is used when user enters the empty string. 194Otherwise the negation of the fringe value in the currently selected 195frame parameter is used." 196 (let ((mode (intern (completing-read 197 (concat 198 "Select fringe mode for " 199 (if all-frames "all frames" "selected frame") 200 " (type ? for list): ") 201 '(("none") ("default") ("left-only") 202 ("right-only") ("half") ("minimal")) 203 nil t)))) 204 (cond ((eq mode 'none) 0) 205 ((eq mode 'default) nil) 206 ((eq mode 'left-only) '(nil . 0)) 207 ((eq mode 'right-only) '(0 . nil)) 208 ((eq mode 'half) '(5 . 5)) 209 ((eq mode 'minimal) '(1 . 1)) 210 ((eq mode (intern "")) 211 (if (eq 0 (cdr (assq 'left-fringe 212 (if all-frames 213 default-frame-alist 214 (frame-parameters (selected-frame)))))) 215 nil 216 0))))) 217 218(defun fringe-mode (&optional mode) 219 "Set the default appearance of fringes on all frames. 220 221When called interactively, query the user for MODE. Valid values 222for MODE include `none', `default', `left-only', `right-only', 223`minimal' and `half'. 224 225When used in a Lisp program, MODE can be a cons cell where the 226integer in car specifies the left fringe width and the integer in 227cdr specifies the right fringe width. MODE can also be a single 228integer that specifies both the left and the right fringe width. 229If a fringe width specification is nil, that means to use the 230default width (8 pixels). This command may round up the left and 231right width specifications to ensure that their sum is a multiple 232of the character width of a frame. It never rounds up a fringe 233width of 0. 234 235Fringe widths set by `set-window-fringes' override the default 236fringe widths set by this command. This command applies to all 237frames that exist and frames to be created in the future. If you 238want to set the default appearance of fringes on the selected 239frame only, see the command `set-fringe-style'." 240 (interactive (list (fringe-query-style 'all-frames))) 241 (set-fringe-mode mode)) 242 243(defun set-fringe-style (&optional mode) 244 "Set the default appearance of fringes on the selected frame. 245 246When called interactively, query the user for MODE. Valid values 247for MODE include `none', `default', `left-only', `right-only', 248`minimal' and `half'. 249 250When used in a Lisp program, MODE can be a cons cell where the 251integer in car specifies the left fringe width and the integer in 252cdr specifies the right fringe width. MODE can also be a single 253integer that specifies both the left and the right fringe width. 254If a fringe width specification is nil, that means to use the 255default width (8 pixels). This command may round up the left and 256right width specifications to ensure that their sum is a multiple 257of the character width of a frame. It never rounds up a fringe 258width of 0. 259 260Fringe widths set by `set-window-fringes' override the default 261fringe widths set by this command. If you want to set the 262default appearance of fringes on all frames, see the command 263`fringe-mode'." 264 (interactive (list (fringe-query-style))) 265 (modify-frame-parameters 266 (selected-frame) 267 (list (cons 'left-fringe (if (consp mode) (car mode) mode)) 268 (cons 'right-fringe (if (consp mode) (cdr mode) mode))))) 269 270(defsubst fringe-columns (side &optional real) 271 "Return the width, measured in columns, of the fringe area on SIDE. 272If optional argument REAL is non-nil, return a real floating point 273number instead of a rounded integer value. 274SIDE must be the symbol `left' or `right'." 275 (funcall (if real '/ 'ceiling) 276 (or (funcall (if (eq side 'left) 'car 'cadr) 277 (window-fringes)) 278 0) 279 (float (frame-char-width)))) 280 281(provide 'fringe) 282 283;;; arch-tag: 6611ef60-0869-47ed-8b93-587ee7d3ff5d 284;;; fringe.el ends here 285