tooltip.el 16.2 KB
Newer Older
Gerd Moellmann's avatar
Gerd Moellmann committed
1 2
;;; tooltip.el --- Show tooltip windows

Gerd Moellmann's avatar
Gerd Moellmann committed
3
;; Copyright (C) 1997, 1999, 2000, 2001 Free Software Foundation, Inc.
Gerd Moellmann's avatar
Gerd Moellmann committed
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51

;; Author: Gerd Moellmann <gerd@acm.org>
;; Keywords: help c mouse tools

;; 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 2, 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; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Put into your `.emacs'

;; (require 'tooltip)
;; (tooltip-mode 1)



;;; Code:

(eval-when-compile
  (require 'cl)
  (require 'comint)
  (require 'gud))

(provide 'tooltip)


;;; Customizable settings

(defgroup tooltip nil
  "Customization group for the `tooltip' package."
  :group 'help
  :group 'c
  :group 'mouse
  :group 'tools
52
  :version "21.1"
Gerd Moellmann's avatar
Gerd Moellmann committed
53 54
  :tag "Tool Tips")

55
(defvar tooltip-mode)
Gerd Moellmann's avatar
Gerd Moellmann committed
56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71

(defcustom tooltip-delay 1.0
  "Seconds to wait before displaying a tooltip the first time."
  :tag "Delay"
  :type 'number
  :group 'tooltip)


(defcustom tooltip-short-delay 0.1
  "Seconds to wait between subsequent tooltips on different items."
  :tag "Short delay"
  :type 'number
  :group 'tooltip)


(defcustom tooltip-recent-seconds 1
72 73
  "Display tooltips if changing tip items within this many seconds.
Do so after `tooltip-short-delay'."
Gerd Moellmann's avatar
Gerd Moellmann committed
74 75 76 77 78
  :tag "Recent seconds"
  :type 'number
  :group 'tooltip)


79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
(defcustom tooltip-x-offset nil
  "Specify an X offset for the display of tooltips.
The offset is relative to the position of the mouse.  It must
be chosen so that the tooltip window doesn't contain the mouse
when it pops up."
  :tag "X offset"
  :type '(choice (const :tag "Default" nil)
		 (integer :tag "Offset" :value 1))
  :group 'tooltip)


(defcustom tooltip-y-offset nil
  "Specify an Y offset for the display of tooltips.
The offset is relative to the position of the mouse.  It must
be chosen so that the tooltip window doesn't contain the mouse
when it pops up."
  :tag "Y offset"
  :type '(choice (const :tag "Default" nil)
		 (integer :tag "Offset" :value 1))
  :group 'tooltip)


Gerd Moellmann's avatar
Gerd Moellmann committed
101 102 103 104 105 106 107 108 109 110
(defcustom tooltip-frame-parameters
  '((name . "tooltip")
    (internal-border-width . 5)
    (border-width . 1))
  "Frame parameters used for tooltips."
  :type 'sexp
  :tag "Frame Parameters"
  :group 'tooltip)


111 112 113 114 115 116 117 118
(defface tooltip
  '((((class color))
     (:background "lightyellow" :foreground "black"))
    (t ()))
  "Face for tooltips."
  :group 'tooltip)


Gerd Moellmann's avatar
Gerd Moellmann committed
119
(defcustom tooltip-gud-tips-p nil
120
  "*Non-nil means show tooltips in GUD sessions."
Gerd Moellmann's avatar
Gerd Moellmann committed
121 122
  :type 'boolean
  :tag "GUD"
123 124 125
  :set #'(lambda (symbol on)
	   (setq tooltip-gud-tips-p on)
	   (if on (tooltip-gud-tips-setup)))
Gerd Moellmann's avatar
Gerd Moellmann committed
126 127 128 129 130 131 132 133 134
  :group 'tooltip)


(defcustom tooltip-gud-modes '(gud-mode c-mode c++-mode)
  "List of modes for which to enable GUD tips."
  :type 'sexp
  :tag "GUD modes"
  :group 'tooltip)

Sam Steingold's avatar
Sam Steingold committed
135

Gerd Moellmann's avatar
Gerd Moellmann committed
136 137 138 139 140 141 142 143 144 145 146 147
(defcustom tooltip-gud-display
  '((eq (tooltip-event-buffer tooltip-gud-event)
	(marker-buffer overlay-arrow-position)))
  "List of forms determining where GUD tooltips are displayed.

Forms in the list are combined with AND.  The default is to display
only tooltips in the buffer containing the overlay arrow."
  :type 'sexp
  :tag "GUD buffers predicate"
  :group 'tooltip)


148
(defcustom tooltip-use-echo-area nil
Dave Love's avatar
Dave Love committed
149 150 151
  "Use the echo area instead of tooltip frames.
This is only relevant GUD display, since otherwise it is equivalent to
turning off Tooltip mode."
152
  :type 'boolean
Dave Love's avatar
Dave Love committed
153
  :tag "Use echo area"
154 155
  :group 'tooltip)

Gerd Moellmann's avatar
Gerd Moellmann committed
156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204

;;; Variables that are not customizable.

(defvar tooltip-hook nil
  "Functions to call to display tooltips.
Each function is called with one argument EVENT which is a copy of
the last mouse movement event that occurred.")


(defvar tooltip-timeout-id nil
  "The id of the timeout started when Emacs becomes idle.")


(defvar tooltip-last-mouse-motion-event nil
  "A copy of the last mouse motion event seen.")


(defvar tooltip-hide-time nil
  "Time when the last tooltip was hidden.")


(defvar tooltip-gud-debugger nil
  "The debugger for which we show tooltips.")



;;; Event accessors

(defun tooltip-event-buffer (event)
  "Return the buffer over which event EVENT occurred.
This might return nil if the event did not occur over a buffer."
  (let ((window (posn-window (event-end event))))
    (and window (window-buffer window))))



;;; Switching tooltips on/off

;; We don't set track-mouse globally because this is a big redisplay
;; problem in buffers having a pre-command-hook or such installed,
;; which does a set-buffer, like the summary buffer of Gnus.  Calling
;; set-buffer prevents redisplay optimizations, so every mouse motion
;; would be accompanied by a full redisplay.

;;;###autoload
(defun tooltip-mode (&optional arg)
  "Mode for tooltip display.
With ARG, turn tooltip mode on if and only if ARG is positive."
  (interactive "P")
205 206
  (unless (fboundp 'x-show-tip)
    (error "Sorry, tooltips are not yet available on this system"))
Gerd Moellmann's avatar
Gerd Moellmann committed
207 208 209 210 211 212 213 214 215 216 217 218 219 220
  (let* ((on (if arg
		 (> (prefix-numeric-value arg) 0)
	       (not tooltip-mode)))
	 (hook-fn (if on 'add-hook 'remove-hook)))
    (setq tooltip-mode on)
    (funcall hook-fn 'change-major-mode-hook 'tooltip-change-major-mode)
    (tooltip-activate-mouse-motions-if-enabled)
    (funcall hook-fn 'pre-command-hook 'tooltip-hide)
    (funcall hook-fn 'tooltip-hook 'tooltip-gud-tips)
    (funcall hook-fn 'tooltip-hook 'tooltip-help-tips)
    (setq show-help-function (if on 'tooltip-show-help-function nil))
    ;; `ignore' is the default binding for mouse movements.
    (define-key global-map [mouse-movement]
      (if on 'tooltip-mouse-motion 'ignore))
221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236
    (tooltip-gud-tips-setup)))

(defun tooltip-gud-tips-setup ()
  "Setup debugger mode-hooks for tooltips."
  (when (and tooltip-mode tooltip-gud-tips-p)
    (global-set-key [S-mouse-3] 'tooltip-gud-toggle-dereference)
    (add-hook 'gdb-mode-hook
	      #'(lambda () (setq tooltip-gud-debugger 'gdb)))
    (add-hook 'sdb-mode-hook
	      #'(lambda () (setq tooltip-gud-debugger 'sdb)))
    (add-hook 'dbx-mode-hook
	      #'(lambda () (setq tooltip-gud-debugger 'dbx)))
    (add-hook 'xdb-mode-hook
	      #'(lambda () (setq tooltip-gud-debugger 'xdb)))
    (add-hook 'perldb-mode-hook
	      #'(lambda () (setq tooltip-gud-debugger 'perldb)))))
Gerd Moellmann's avatar
Gerd Moellmann committed
237 238 239 240 241 242

;;; Timeout for tooltip display

(defun tooltip-delay ()
  "Return the delay in seconds for the next tooltip."
  (let ((delay tooltip-delay)
Sam Steingold's avatar
Sam Steingold committed
243
	(now (float-time)))
Gerd Moellmann's avatar
Gerd Moellmann committed
244 245 246 247 248 249
    (when (and tooltip-hide-time
	       (< (- now tooltip-hide-time) tooltip-recent-seconds))
      (setq delay tooltip-short-delay))
    delay))


Gerd Moellmann's avatar
Gerd Moellmann committed
250
(defun tooltip-cancel-delayed-tip ()
Gerd Moellmann's avatar
Gerd Moellmann committed
251 252 253 254 255 256
  "Disable the tooltip timeout."
  (when tooltip-timeout-id
    (disable-timeout tooltip-timeout-id)
    (setq tooltip-timeout-id nil)))


Gerd Moellmann's avatar
Gerd Moellmann committed
257
(defun tooltip-start-delayed-tip ()
Gerd Moellmann's avatar
Gerd Moellmann committed
258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307
  "Add a one-shot timeout to call function tooltip-timeout."
  (setq tooltip-timeout-id
	(add-timeout (tooltip-delay) 'tooltip-timeout nil)))


(defun tooltip-timeout (object)
  "Function called when timer with id tooltip-timeout-id fires."
  (run-hook-with-args-until-success 'tooltip-hook
				    tooltip-last-mouse-motion-event))



;;; Reacting on mouse movements

(defun tooltip-change-major-mode ()
  "Function added to `change-major-mode-hook' when tooltip mode is on."
  (add-hook 'post-command-hook 'tooltip-activate-mouse-motions-if-enabled))


(defun tooltip-activate-mouse-motions-if-enabled ()
  "Reconsider for all buffers whether mouse motion events are desired."
  (remove-hook 'post-command-hook 'tooltip-activate-mouse-motions-if-enabled)
  (let ((buffers (buffer-list)))
    (save-excursion
      (while buffers
	(set-buffer (car buffers))
	(if (and tooltip-mode
		 tooltip-gud-tips-p
		 (memq major-mode tooltip-gud-modes))
	    (tooltip-activate-mouse-motions t)
	  (tooltip-activate-mouse-motions nil))
	(setq buffers (cdr buffers))))))


(defun tooltip-activate-mouse-motions (activatep)
  "Activate/deactivate mouse motion events for the current buffer.
ACTIVATEP non-nil means activate mouse motion events."
  (if activatep
      (progn
	(make-local-variable 'track-mouse)
	(setq track-mouse t))
    (kill-local-variable 'track-mouse)))


(defun tooltip-mouse-motion (event)
  "Command handler for mouse movement events in `global-map'."
  (interactive "e")
  (tooltip-hide)
  (when (car (mouse-pixel-position))
    (setq tooltip-last-mouse-motion-event (copy-sequence event))
Gerd Moellmann's avatar
Gerd Moellmann committed
308
    (tooltip-start-delayed-tip)))
Gerd Moellmann's avatar
Gerd Moellmann committed
309 310 311 312 313



;;; Displaying tips

314 315 316 317 318 319 320 321 322 323 324
(defun tooltip-set-param (alist key value)
  "Change the value of KEY in alist ALIAS to VALUE.
If there's no association for KEY in ALIST, add one, otherwise 
change the existing association.  Value is the resulting alist."
  (let ((param (assq key alist)))
    (if (consp param)
	(setcdr param value)
      (push (cons key value) alist))
    alist))


Gerd Moellmann's avatar
Gerd Moellmann committed
325 326
(defun tooltip-show (text)
  "Show a tooltip window at the current mouse position displaying TEXT."
327 328
  (if tooltip-use-echo-area
      (message "%s" text)
329
    (condition-case error
330 331 332
	(let ((params (copy-sequence tooltip-frame-parameters))
	      (fg (face-attribute 'tooltip :foreground))
	      (bg (face-attribute 'tooltip :background)))
Gerd Moellmann's avatar
Gerd Moellmann committed
333 334 335 336 337
	  (when (stringp fg)
	    (setq params (tooltip-set-param params 'foreground-color fg))
	    (setq params (tooltip-set-param params 'border-color fg)))
	  (when (stringp bg)
	    (setq params (tooltip-set-param params 'background-color bg)))
338 339
	  (x-show-tip (propertize text 'face 'tooltip)
		      (selected-frame)
Gerd Moellmann's avatar
Gerd Moellmann committed
340
		      params
341 342 343
		      nil
		      tooltip-x-offset
		      tooltip-y-offset))
344 345 346 347 348
      (error 
       (message "Error while displaying tooltip: %s" error)
       (sit-for 1)
       (message "%s" text)))))

Gerd Moellmann's avatar
Gerd Moellmann committed
349 350 351 352

(defun tooltip-hide (&optional ignored-arg)
  "Hide a tooltip, if one is displayed.
Value is non-nil if tooltip was open."
Gerd Moellmann's avatar
Gerd Moellmann committed
353
  (tooltip-cancel-delayed-tip)
Gerd Moellmann's avatar
Gerd Moellmann committed
354
  (when (x-hide-tip)
Sam Steingold's avatar
Sam Steingold committed
355
    (setq tooltip-hide-time (float-time))))
Gerd Moellmann's avatar
Gerd Moellmann committed
356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440



;;; Debugger-related functions

(defun tooltip-identifier-from-point (point)
  "Extract the identifier at POINT, if any.
Value is nil if no identifier exists at point.  Identifier extraction
is based on the current syntax table."
  (save-excursion
    (goto-char point)
    (let ((start (progn (skip-syntax-backward "w_") (point))))
      (unless (looking-at "[0-9]")
	(skip-syntax-forward "w_")
	(when (> (point) start)
	  (buffer-substring start (point)))))))


(defmacro tooltip-region-active-p ()
  "Value is non-nil if the region is currently active."
  (if (string-match "^GNU" (emacs-version))
      `(and transient-mark-mode mark-active)
    `(region-active-p)))


(defun tooltip-expr-to-print (event)
  "Return an expression that should be printed for EVENT.
If a region is active and the mouse is inside the region, print
the region.  Otherwise, figure out the identifier around the point
where the mouse is."
  (save-excursion
    (set-buffer (tooltip-event-buffer event))
    (let ((point (posn-point (event-end event))))
      (if (tooltip-region-active-p)
	  (when (and (<= (region-beginning) point) (<= point (region-end)))
	    (buffer-substring (region-beginning) (region-end)))
	(tooltip-identifier-from-point point)))))


(defun tooltip-process-prompt-regexp (process)
  "Return regexp matching the prompt of PROCESS at the end of a string.
The prompt is taken from the value of COMINT-PROMPT-REGEXP in the buffer
of PROCESS."
  (let ((prompt-regexp (save-excursion
			 (set-buffer (process-buffer process))
			 comint-prompt-regexp)))
    ;; Most start with `^' but the one for `sdb' cannot be easily
    ;; stripped.  Code the prompt for `sdb' fixed here.
    (if (= (aref prompt-regexp 0) ?^)
	(setq prompt-regexp (substring prompt-regexp 1))
      (setq prompt-regexp "\\*"))
    (concat "\n*" prompt-regexp "$")))


(defun tooltip-strip-prompt (process output)
  "Return OUTPUT with any prompt of PROCESS stripped from its end."
  (let ((prompt-regexp (tooltip-process-prompt-regexp process)))
    (save-match-data
      (when (string-match prompt-regexp output)
	(setq output (substring output 0 (match-beginning 0)))))
    output))



;;; Tips for `gud'

(defvar tooltip-gud-original-filter nil
  "Process filter to restore after GUD output has been received.")


(defvar tooltip-gud-dereference nil
  "Non-nil means print expressions with a `*' in front of them.
For C this would dereference a pointer expression.")


(defvar tooltip-gud-event nil
  "The mouse movement event that led to a tooltip display.
This event can be examined by forms in TOOLTIP-GUD-DISPLAY.")


(defvar tooltip-gud-debugger nil
  "A symbol describing the debugger running under GUD.")


(defun tooltip-gud-toggle-dereference ()
441
  "Toggle whether tooltips should show `* expr' or `expr'."
Gerd Moellmann's avatar
Gerd Moellmann committed
442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464
  (interactive)
  (setq tooltip-gud-dereference (not tooltip-gud-dereference))
  (when (interactive-p)
    (message "Dereferencing is now %s."
	     (if tooltip-gud-dereference "on" "off"))))


(defun tooltip-gud-process-output (process output)
  "Process debugger output and show it in a tooltip window."
  (set-process-filter process tooltip-gud-original-filter)
  (tooltip-show (tooltip-strip-prompt process output)))


(defun tooltip-gud-print-command (expr)
  "Return a suitable command to print the expression EXPR.
If TOOLTIP-GUD-DEREFERENCE is t, also prepend a `*' to EXPR."
  (when tooltip-gud-dereference
    (setq expr (concat "*" expr)))
  (case tooltip-gud-debugger
    ((gdb dbx) (concat "print " expr))
    (xdb (concat "p " expr))
    (sdb (concat expr "/"))
    (perldb expr)))
Sam Steingold's avatar
Sam Steingold committed
465

Gerd Moellmann's avatar
Gerd Moellmann committed
466 467

(defun tooltip-gud-tips (event)
468 469 470 471
  "Show tip for identifier or selection under the mouse.
The mouse must either point at an identifier or inside a selected
region for the tip window to be shown.  If tooltip-gud-dereference is t,
add a `*' in front of the printed expression.
Gerd Moellmann's avatar
Gerd Moellmann committed
472 473 474 475 476 477 478 479 480 481 482 483 484

This function must return nil if it doesn't handle EVENT."
  (let (gud-buffer process)
    (when (and (eventp event)
	       tooltip-gud-tips-p
	       (boundp 'gud-comint-buffer)
	       (setq gud-buffer gud-comint-buffer)
	       (setq process (get-buffer-process gud-buffer))
	       (posn-point (event-end event))
	       (progn (setq tooltip-gud-event event)
		      (eval (cons 'and tooltip-gud-display))))
      (let ((expr (tooltip-expr-to-print event)))
	(when expr
485 486 487 488 489 490
	  (let ((cmd (tooltip-gud-print-command expr)))
	    (unless (null cmd)	       ; CMD can be nil if unknown debugger
	      (setq tooltip-gud-original-filter (process-filter process))
	      (set-process-filter process 'tooltip-gud-process-output)
	      (gud-basic-call cmd)
	      expr)))))))
Gerd Moellmann's avatar
Gerd Moellmann committed
491 492 493 494 495 496 497 498 499 500 501 502 503 504


;;; Tooltip help.

(defvar tooltip-help-message nil
  "The last help message received via `tooltip-show-help-function'.")


(defun tooltip-show-help-function (msg)
  "Function installed as `show-help-function'.
MSG is either a help string to display, or nil to cancel the display."
  (let ((previous-help tooltip-help-message))
    (setq tooltip-help-message msg)
    (cond ((null msg)
Gerd Moellmann's avatar
Gerd Moellmann committed
505 506
	   ;; Cancel display.  This also cancels a delayed tip, if
	   ;; there is one.
Gerd Moellmann's avatar
Gerd Moellmann committed
507
	   (tooltip-hide))
Gerd Moellmann's avatar
Gerd Moellmann committed
508 509 510 511
	  ((equal previous-help msg)
	   ;; Same help as before (but possibly the mouse has moved).
	   ;; Keep what we have.
	   )
Gerd Moellmann's avatar
Gerd Moellmann committed
512
	  (t
Gerd Moellmann's avatar
Gerd Moellmann committed
513 514 515 516
	   ;; A different help.  Remove a previous tooltip, and 
	   ;; display a new one, with some delay.
	   (tooltip-hide)
	   (tooltip-start-delayed-tip)))))
Gerd Moellmann's avatar
Gerd Moellmann committed
517 518 519 520


(defun tooltip-help-tips (event)
  "Hook function to display a help tooltip.
Gerd Moellmann's avatar
Gerd Moellmann committed
521 522
This is installed on the hook `tooltip-hook', which is run when
the the timer with ID `tooltip-timeout-id' fires.
Gerd Moellmann's avatar
Gerd Moellmann committed
523 524 525 526 527 528 529
Value is non-nil if this function handled the tip."
  (when (stringp tooltip-help-message)
    (tooltip-show tooltip-help-message)
    t))



530 531 532
;;; Do this after all functions have been defined that are called from
;;; `tooltip-mode'.  The actual default value of `tooltip-mode' is set
;;; in startup.el.
533 534 535 536 537 538 539 540 541

;;;###autoload
(defcustom tooltip-mode nil
  "Toggle tooltip-mode.
Setting this variable directly does not take effect;
use either \\[customize] or the function `tooltip-mode'."
  :set (lambda (symbol value)
	 (tooltip-mode (or value 0)))
  :initialize 'custom-initialize-default
Gerd Moellmann's avatar
Gerd Moellmann committed
542 543 544 545 546 547
  :type 'boolean
  :require 'tooltip
  :group 'tooltip)


;;; tooltip.el ends here