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1 | @c -*-texinfo-*- |
2 | @c This is part of the GNU Emacs Lisp Reference Manual. | |
11ef2a3b | 3 | @c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2002 |
177c0ea7 | 4 | @c Free Software Foundation, Inc. |
d25390d0 RS |
5 | @c See the file elisp.texi for copying conditions. |
6 | @setfilename ../info/frames | |
7 | @node Frames, Positions, Windows, Top | |
8 | @chapter Frames | |
9 | @cindex frame | |
10 | ||
1a426e9b | 11 | A @dfn{frame} is a rectangle on the screen that contains one or more |
d25390d0 | 12 | Emacs windows. A frame initially contains a single main window (plus |
61cfa852 | 13 | perhaps a minibuffer window), which you can subdivide vertically or |
d25390d0 RS |
14 | horizontally into smaller windows. |
15 | ||
16 | @cindex terminal frame | |
22697dac | 17 | When Emacs runs on a text-only terminal, it starts with one |
eaac2be1 | 18 | @dfn{terminal frame}. If you create additional ones, Emacs displays |
22697dac KH |
19 | one and only one at any given time---on the terminal screen, of course. |
20 | ||
a9f0a989 | 21 | @cindex window frame |
969fe9b5 | 22 | When Emacs communicates directly with a supported window system, such |
e294b7f1 | 23 | as X, it does not have a terminal frame; instead, it starts with |
969fe9b5 RS |
24 | a single @dfn{window frame}, but you can create more, and Emacs can |
25 | display several such frames at once as is usual for window systems. | |
d25390d0 RS |
26 | |
27 | @defun framep object | |
8241495d RS |
28 | This predicate returns a non-@code{nil} value if @var{object} is a |
29 | frame, and @code{nil} otherwise. For a frame, the value indicates which | |
30 | kind of display the frame uses: | |
31 | ||
32 | @table @code | |
33 | @item x | |
34 | The frame is displayed in an X window. | |
35 | @item t | |
36 | A terminal frame on a character display. | |
37 | @item mac | |
38 | The frame is displayed on a Macintosh. | |
39 | @item w32 | |
40 | The frame is displayed on MS-Windows 9X/NT. | |
41 | @item pc | |
42 | The frame is displayed on an MS-DOS terminal. | |
43 | @end table | |
d25390d0 RS |
44 | @end defun |
45 | ||
46 | @menu | |
22697dac | 47 | * Creating Frames:: Creating additional frames. |
969fe9b5 | 48 | * Multiple Displays:: Creating frames on other displays. |
d25390d0 | 49 | * Frame Parameters:: Controlling frame size, position, font, etc. |
22697dac | 50 | * Frame Titles:: Automatic updating of frame titles. |
d25390d0 RS |
51 | * Deleting Frames:: Frames last until explicitly deleted. |
52 | * Finding All Frames:: How to examine all existing frames. | |
53 | * Frames and Windows:: A frame contains windows; | |
54 | display of text always works through windows. | |
55 | * Minibuffers and Frames:: How a frame finds the minibuffer to use. | |
56 | * Input Focus:: Specifying the selected frame. | |
57 | * Visibility of Frames:: Frames may be visible or invisible, or icons. | |
969fe9b5 | 58 | * Raising and Lowering:: Raising a frame makes it hide other windows; |
d25390d0 RS |
59 | lowering it makes the others hide them. |
60 | * Frame Configurations:: Saving the state of all frames. | |
61 | * Mouse Tracking:: Getting events that say when the mouse moves. | |
62 | * Mouse Position:: Asking where the mouse is, or moving it. | |
63 | * Pop-Up Menus:: Displaying a menu for the user to select from. | |
64 | * Dialog Boxes:: Displaying a box to ask yes or no. | |
bd998259 | 65 | * Pointer Shapes:: Specifying the shape of the mouse pointer. |
969fe9b5 | 66 | * Window System Selections:: Transferring text to and from other X clients. |
bfe721d1 | 67 | * Color Names:: Getting the definitions of color names. |
8241495d | 68 | * Text Terminal Colors:: Defining colors for text-only terminals. |
d25390d0 | 69 | * Resources:: Getting resource values from the server. |
a065c889 | 70 | * Display Feature Testing:: Determining the features of a terminal. |
d25390d0 RS |
71 | @end menu |
72 | ||
177c0ea7 | 73 | @xref{Display}, for information about the related topic of |
1911e6e5 | 74 | controlling Emacs redisplay. |
d25390d0 RS |
75 | |
76 | @node Creating Frames | |
77 | @section Creating Frames | |
78 | ||
79 | To create a new frame, call the function @code{make-frame}. | |
80 | ||
1a426e9b | 81 | @defun make-frame &optional alist |
969fe9b5 RS |
82 | This function creates a new frame. If you are using a supported window |
83 | system, it makes a window frame; otherwise, it makes a terminal frame. | |
d25390d0 RS |
84 | |
85 | The argument is an alist specifying frame parameters. Any parameters | |
86 | not mentioned in @var{alist} default according to the value of the | |
bfe721d1 | 87 | variable @code{default-frame-alist}; parameters not specified even there |
969fe9b5 RS |
88 | default from the standard X resources or whatever is used instead on |
89 | your system. | |
d25390d0 RS |
90 | |
91 | The set of possible parameters depends in principle on what kind of | |
969fe9b5 | 92 | window system Emacs uses to display its frames. @xref{Window Frame |
22697dac | 93 | Parameters}, for documentation of individual parameters you can specify. |
d25390d0 RS |
94 | @end defun |
95 | ||
d25390d0 RS |
96 | @defvar before-make-frame-hook |
97 | A normal hook run by @code{make-frame} before it actually creates the | |
98 | frame. | |
99 | @end defvar | |
100 | ||
8241495d RS |
101 | @defvar after-make-frame-functions |
102 | @tindex after-make-frame-functions | |
f9f59935 | 103 | An abnormal hook run by @code{make-frame} after it creates the frame. |
916a89db | 104 | Each function in @code{after-make-frame-functions} receives one argument, the |
f9f59935 | 105 | frame just created. |
d25390d0 RS |
106 | @end defvar |
107 | ||
22697dac KH |
108 | @node Multiple Displays |
109 | @section Multiple Displays | |
1911e6e5 | 110 | @cindex multiple X displays |
22697dac KH |
111 | @cindex displays, multiple |
112 | ||
1911e6e5 | 113 | A single Emacs can talk to more than one X display. |
22697dac KH |
114 | Initially, Emacs uses just one display---the one chosen with the |
115 | @code{DISPLAY} environment variable or with the @samp{--display} option | |
116 | (@pxref{Initial Options,,, emacs, The GNU Emacs Manual}). To connect to | |
117 | another display, use the command @code{make-frame-on-display} or specify | |
118 | the @code{display} frame parameter when you create the frame. | |
119 | ||
120 | Emacs treats each X server as a separate terminal, giving each one its | |
5df7058c EZ |
121 | own selected frame and its own minibuffer windows. However, only one of |
122 | those frames is ``@emph{the} selected frame'' at any given moment, see | |
123 | @ref{Input Focus}. | |
1911e6e5 RS |
124 | |
125 | A few Lisp variables are @dfn{terminal-local}; that is, they have a | |
126 | separate binding for each terminal. The binding in effect at any time | |
127 | is the one for the terminal that the currently selected frame belongs | |
128 | to. These variables include @code{default-minibuffer-frame}, | |
129 | @code{defining-kbd-macro}, @code{last-kbd-macro}, and | |
130 | @code{system-key-alist}. They are always terminal-local, and can never | |
131 | be buffer-local (@pxref{Buffer-Local Variables}) or frame-local. | |
22697dac KH |
132 | |
133 | A single X server can handle more than one screen. A display name | |
1911e6e5 | 134 | @samp{@var{host}:@var{server}.@var{screen}} has three parts; the last |
22697dac KH |
135 | part specifies the screen number for a given server. When you use two |
136 | screens belonging to one server, Emacs knows by the similarity in their | |
137 | names that they share a single keyboard, and it treats them as a single | |
138 | terminal. | |
139 | ||
140 | @deffn Command make-frame-on-display display &optional parameters | |
141 | This creates a new frame on display @var{display}, taking the other | |
142 | frame parameters from @var{parameters}. Aside from the @var{display} | |
143 | argument, it is like @code{make-frame} (@pxref{Creating Frames}). | |
144 | @end deffn | |
145 | ||
146 | @defun x-display-list | |
147 | This returns a list that indicates which X displays Emacs has a | |
bfe721d1 KH |
148 | connection to. The elements of the list are strings, and each one is |
149 | a display name. | |
22697dac KH |
150 | @end defun |
151 | ||
94886883 | 152 | @defun x-open-connection display &optional xrm-string must-succeed |
22697dac KH |
153 | This function opens a connection to the X display @var{display}. It |
154 | does not create a frame on that display, but it permits you to check | |
155 | that communication can be established with that display. | |
156 | ||
f9f59935 | 157 | The optional argument @var{xrm-string}, if not @code{nil}, is a |
bfe721d1 KH |
158 | string of resource names and values, in the same format used in the |
159 | @file{.Xresources} file. The values you specify override the resource | |
160 | values recorded in the X server itself; they apply to all Emacs frames | |
161 | created on this display. Here's an example of what this string might | |
162 | look like: | |
163 | ||
164 | @example | |
165 | "*BorderWidth: 3\n*InternalBorder: 2\n" | |
166 | @end example | |
167 | ||
168 | @xref{Resources}. | |
94886883 GM |
169 | |
170 | If @var{must-succeed} is non-@code{nil}, failure to open the connection | |
171 | terminates Emacs. Otherwise, it is an ordinary Lisp error. | |
22697dac KH |
172 | @end defun |
173 | ||
174 | @defun x-close-connection display | |
175 | This function closes the connection to display @var{display}. Before | |
176 | you can do this, you must first delete all the frames that were open on | |
177 | that display (@pxref{Deleting Frames}). | |
178 | @end defun | |
179 | ||
d25390d0 RS |
180 | @node Frame Parameters |
181 | @section Frame Parameters | |
182 | ||
8241495d | 183 | A frame has many parameters that control its appearance and behavior. |
d25390d0 RS |
184 | Just what parameters a frame has depends on what display mechanism it |
185 | uses. | |
186 | ||
8241495d RS |
187 | Frame parameters exist mostly for the sake of window systems. A |
188 | terminal frame has a few parameters, mostly for compatibility's sake; | |
189 | only the @code{height}, @code{width}, @code{name}, @code{title}, | |
190 | @code{menu-bar-lines}, @code{buffer-list} and @code{buffer-predicate} | |
191 | parameters do something special. If the terminal supports colors, the | |
192 | parameters @code{foreground-color}, @code{background-color}, | |
193 | @code{background-mode} and @code{display-type} are also meaningful. | |
d25390d0 RS |
194 | |
195 | @menu | |
196 | * Parameter Access:: How to change a frame's parameters. | |
197 | * Initial Parameters:: Specifying frame parameters when you make a frame. | |
969fe9b5 | 198 | * Window Frame Parameters:: List of frame parameters for window systems. |
fb9b5ab7 | 199 | * Size and Position:: Changing the size and position of a frame. |
d25390d0 RS |
200 | @end menu |
201 | ||
202 | @node Parameter Access | |
203 | @subsection Access to Frame Parameters | |
204 | ||
205 | These functions let you read and change the parameter values of a | |
206 | frame. | |
207 | ||
94886883 GM |
208 | @defun frame-parameter frame parameter |
209 | @tindex frame-parameter | |
210 | This function returns the value of the parameter named @var{parameter} | |
211 | of @var{frame}. If @var{frame} is @code{nil}, it returns the | |
212 | selected frame's parameter. | |
213 | @end defun | |
214 | ||
d25390d0 RS |
215 | @defun frame-parameters frame |
216 | The function @code{frame-parameters} returns an alist listing all the | |
217 | parameters of @var{frame} and their values. | |
218 | @end defun | |
219 | ||
220 | @defun modify-frame-parameters frame alist | |
221 | This function alters the parameters of frame @var{frame} based on the | |
222 | elements of @var{alist}. Each element of @var{alist} has the form | |
223 | @code{(@var{parm} . @var{value})}, where @var{parm} is a symbol naming a | |
224 | parameter. If you don't mention a parameter in @var{alist}, its value | |
225 | doesn't change. | |
226 | @end defun | |
227 | ||
228 | @node Initial Parameters | |
229 | @subsection Initial Frame Parameters | |
230 | ||
231 | You can specify the parameters for the initial startup frame | |
a40d4712 | 232 | by setting @code{initial-frame-alist} in your init file (@pxref{Init File}). |
d25390d0 RS |
233 | |
234 | @defvar initial-frame-alist | |
235 | This variable's value is an alist of parameter values used when creating | |
969fe9b5 | 236 | the initial window frame. You can set this variable to specify the |
761a9cbf RS |
237 | appearance of the initial frame without altering subsequent frames. |
238 | Each element has the form: | |
1e2300d3 RS |
239 | |
240 | @example | |
241 | (@var{parameter} . @var{value}) | |
242 | @end example | |
243 | ||
a40d4712 | 244 | Emacs creates the initial frame before it reads your init |
1e2300d3 RS |
245 | file. After reading that file, Emacs checks @code{initial-frame-alist}, |
246 | and applies the parameter settings in the altered value to the already | |
247 | created initial frame. | |
248 | ||
bfe721d1 KH |
249 | If these settings affect the frame geometry and appearance, you'll see |
250 | the frame appear with the wrong ones and then change to the specified | |
251 | ones. If that bothers you, you can specify the same geometry and | |
8241495d | 252 | appearance with X resources; those do take effect before the frame is |
61f7e0f5 | 253 | created. @xref{X Resources,, X Resources, emacs, The GNU Emacs Manual}. |
1e2300d3 RS |
254 | |
255 | X resource settings typically apply to all frames. If you want to | |
256 | specify some X resources solely for the sake of the initial frame, and | |
257 | you don't want them to apply to subsequent frames, here's how to achieve | |
258 | this. Specify parameters in @code{default-frame-alist} to override the | |
259 | X resources for subsequent frames; then, to prevent these from affecting | |
260 | the initial frame, specify the same parameters in | |
261 | @code{initial-frame-alist} with values that match the X resources. | |
d25390d0 RS |
262 | @end defvar |
263 | ||
bfe721d1 KH |
264 | If these parameters specify a separate minibuffer-only frame with |
265 | @code{(minibuffer . nil)}, and you have not created one, Emacs creates | |
266 | one for you. | |
d25390d0 RS |
267 | |
268 | @defvar minibuffer-frame-alist | |
269 | This variable's value is an alist of parameter values used when creating | |
270 | an initial minibuffer-only frame---if such a frame is needed, according | |
271 | to the parameters for the main initial frame. | |
272 | @end defvar | |
273 | ||
1e2300d3 | 274 | @defvar default-frame-alist |
761a9cbf | 275 | This is an alist specifying default values of frame parameters for all |
969fe9b5 RS |
276 | Emacs frames---the first frame, and subsequent frames. When using the X |
277 | Window System, you can get the same results by means of X resources | |
278 | in many cases. | |
1e2300d3 RS |
279 | @end defvar |
280 | ||
bfe721d1 KH |
281 | See also @code{special-display-frame-alist}, in @ref{Choosing Window}. |
282 | ||
1e2300d3 RS |
283 | If you use options that specify window appearance when you invoke Emacs, |
284 | they take effect by adding elements to @code{default-frame-alist}. One | |
bfe721d1 KH |
285 | exception is @samp{-geometry}, which adds the specified position to |
286 | @code{initial-frame-alist} instead. @xref{Command Arguments,,, emacs, | |
287 | The GNU Emacs Manual}. | |
1e2300d3 | 288 | |
969fe9b5 RS |
289 | @node Window Frame Parameters |
290 | @subsection Window Frame Parameters | |
d25390d0 RS |
291 | |
292 | Just what parameters a frame has depends on what display mechanism it | |
969fe9b5 RS |
293 | uses. Here is a table of the parameters that have special meanings in a |
294 | window frame; of these, @code{name}, @code{title}, @code{height}, | |
295 | @code{width}, @code{buffer-list} and @code{buffer-predicate} provide | |
7b32356b EZ |
296 | meaningful information in terminal frames, and @code{tty-color-mode} |
297 | is meaningful @emph{only} in terminal frames. | |
d25390d0 RS |
298 | |
299 | @table @code | |
a9f0a989 RS |
300 | @item display |
301 | The display on which to open this frame. It should be a string of the | |
302 | form @code{"@var{host}:@var{dpy}.@var{screen}"}, just like the | |
303 | @code{DISPLAY} environment variable. | |
304 | ||
969fe9b5 RS |
305 | @item title |
306 | If a frame has a non-@code{nil} title, it appears in the window system's | |
307 | border for the frame, and also in the mode line of windows in that frame | |
308 | if @code{mode-line-frame-identification} uses @samp{%F} | |
309 | (@pxref{%-Constructs}). This is normally the case when Emacs is not | |
310 | using a window system, and can only display one frame at a time. | |
311 | @xref{Frame Titles}. | |
312 | ||
d25390d0 | 313 | @item name |
969fe9b5 RS |
314 | The name of the frame. The frame name serves as a default for the frame |
315 | title, if the @code{title} parameter is unspecified or @code{nil}. If | |
316 | you don't specify a name, Emacs sets the frame name automatically | |
317 | (@pxref{Frame Titles}). | |
d25390d0 RS |
318 | |
319 | If you specify the frame name explicitly when you create the frame, the | |
320 | name is also used (instead of the name of the Emacs executable) when | |
321 | looking up X resources for the frame. | |
322 | ||
323 | @item left | |
22697dac KH |
324 | The screen position of the left edge, in pixels, with respect to the |
325 | left edge of the screen. The value may be a positive number @var{pos}, | |
326 | or a list of the form @code{(+ @var{pos})} which permits specifying a | |
327 | negative @var{pos} value. | |
328 | ||
329 | A negative number @minus{}@var{pos}, or a list of the form @code{(- | |
330 | @var{pos})}, actually specifies the position of the right edge of the | |
bfe721d1 | 331 | window with respect to the right edge of the screen. A positive value |
969fe9b5 RS |
332 | of @var{pos} counts toward the left. @strong{Reminder:} if the |
333 | parameter is a negative integer @minus{}@var{pos}, then @var{pos} is | |
334 | positive. | |
d25390d0 | 335 | |
53c47801 RS |
336 | Some window managers ignore program-specified positions. If you want to |
337 | be sure the position you specify is not ignored, specify a | |
338 | non-@code{nil} value for the @code{user-position} parameter as well. | |
339 | ||
d25390d0 | 340 | @item top |
22697dac KH |
341 | The screen position of the top edge, in pixels, with respect to the |
342 | top edge of the screen. The value may be a positive number @var{pos}, | |
343 | or a list of the form @code{(+ @var{pos})} which permits specifying a | |
344 | negative @var{pos} value. | |
345 | ||
346 | A negative number @minus{}@var{pos}, or a list of the form @code{(- | |
347 | @var{pos})}, actually specifies the position of the bottom edge of the | |
bfe721d1 | 348 | window with respect to the bottom edge of the screen. A positive value |
969fe9b5 RS |
349 | of @var{pos} counts toward the top. @strong{Reminder:} if the |
350 | parameter is a negative integer @minus{}@var{pos}, then @var{pos} is | |
351 | positive. | |
bd998259 | 352 | |
53c47801 RS |
353 | Some window managers ignore program-specified positions. If you want to |
354 | be sure the position you specify is not ignored, specify a | |
355 | non-@code{nil} value for the @code{user-position} parameter as well. | |
356 | ||
906848bd RS |
357 | @item icon-left |
358 | The screen position of the left edge @emph{of the frame's icon}, in | |
359 | pixels, counting from the left edge of the screen. This takes effect if | |
360 | and when the frame is iconified. | |
361 | ||
362 | @item icon-top | |
363 | The screen position of the top edge @emph{of the frame's icon}, in | |
364 | pixels, counting from the top edge of the screen. This takes effect if | |
365 | and when the frame is iconified. | |
366 | ||
bd998259 | 367 | @item user-position |
cee8c3b3 RS |
368 | When you create a frame and specify its screen position with the |
369 | @code{left} and @code{top} parameters, use this parameter to say whether | |
370 | the specified position was user-specified (explicitly requested in some | |
371 | way by a human user) or merely program-specified (chosen by a program). | |
372 | A non-@code{nil} value says the position was user-specified. | |
373 | ||
374 | Window managers generally heed user-specified positions, and some heed | |
375 | program-specified positions too. But many ignore program-specified | |
376 | positions, placing the window in a default fashion or letting the user | |
377 | place it with the mouse. Some window managers, including @code{twm}, | |
378 | let the user specify whether to obey program-specified positions or | |
379 | ignore them. | |
380 | ||
381 | When you call @code{make-frame}, you should specify a non-@code{nil} | |
382 | value for this parameter if the values of the @code{left} and @code{top} | |
383 | parameters represent the user's stated preference; otherwise, use | |
384 | @code{nil}. | |
d25390d0 RS |
385 | |
386 | @item height | |
fb9b5ab7 RS |
387 | The height of the frame contents, in characters. (To get the height in |
388 | pixels, call @code{frame-pixel-height}; see @ref{Size and Position}.) | |
d25390d0 RS |
389 | |
390 | @item width | |
fb9b5ab7 RS |
391 | The width of the frame contents, in characters. (To get the height in |
392 | pixels, call @code{frame-pixel-width}; see @ref{Size and Position}.) | |
d25390d0 | 393 | |
560e5397 EZ |
394 | @item fullscreen |
395 | Specify that width, height or both shall be set to the size of the screen. | |
396 | The value @code{fullwidth} specifies that width shall be the size of the | |
397 | screen. The value @code{fullheight} specifies that height shall be the | |
398 | size of the screen. The value @code{fullboth} specifies that both the | |
399 | width and the height shall be set to the size of the screen. | |
400 | ||
d25390d0 | 401 | @item window-id |
b6954afd RS |
402 | The number of the window-system window used by the frame |
403 | to contain the actual Emacs windows. | |
404 | ||
405 | @item outer-window-id | |
406 | The number of the outermost window-system window used for the whole frame. | |
d25390d0 RS |
407 | |
408 | @item minibuffer | |
409 | Whether this frame has its own minibuffer. The value @code{t} means | |
410 | yes, @code{nil} means no, @code{only} means this frame is just a | |
bfe721d1 KH |
411 | minibuffer. If the value is a minibuffer window (in some other frame), |
412 | the new frame uses that minibuffer. | |
d25390d0 | 413 | |
22697dac KH |
414 | @item buffer-predicate |
415 | The buffer-predicate function for this frame. The function | |
416 | @code{other-buffer} uses this predicate (from the selected frame) to | |
417 | decide which buffers it should consider, if the predicate is not | |
969fe9b5 | 418 | @code{nil}. It calls the predicate with one argument, a buffer, once for |
22697dac KH |
419 | each buffer; if the predicate returns a non-@code{nil} value, it |
420 | considers that buffer. | |
421 | ||
f9f59935 | 422 | @item buffer-list |
969fe9b5 RS |
423 | A list of buffers that have been selected in this frame, |
424 | ordered most-recently-selected first. | |
f9f59935 | 425 | |
d25390d0 RS |
426 | @item font |
427 | The name of the font for displaying text in the frame. This is a | |
a9f0a989 | 428 | string, either a valid font name for your system or the name of an Emacs |
75708135 | 429 | fontset (@pxref{Fontsets}). Changing this frame parameter on a frame |
8241495d RS |
430 | also changes the font-related attributes of the default face on that |
431 | frame. | |
d25390d0 RS |
432 | |
433 | @item auto-raise | |
434 | Whether selecting the frame raises it (non-@code{nil} means yes). | |
435 | ||
436 | @item auto-lower | |
437 | Whether deselecting the frame lowers it (non-@code{nil} means yes). | |
438 | ||
439 | @item vertical-scroll-bars | |
f9f59935 RS |
440 | Whether the frame has scroll bars for vertical scrolling, and which side |
441 | of the frame they should be on. The possible values are @code{left}, | |
442 | @code{right}, and @code{nil} for no scroll bars. | |
d25390d0 RS |
443 | |
444 | @item horizontal-scroll-bars | |
445 | Whether the frame has scroll bars for horizontal scrolling | |
446 | (non-@code{nil} means yes). (Horizontal scroll bars are not currently | |
447 | implemented.) | |
448 | ||
22697dac KH |
449 | @item scroll-bar-width |
450 | The width of the vertical scroll bar, in pixels. | |
451 | ||
d25390d0 | 452 | @item icon-type |
fd3e5741 RS |
453 | The type of icon to use for this frame when it is iconified. If the |
454 | value is a string, that specifies a file containing a bitmap to use. | |
455 | Any other non-@code{nil} value specifies the default bitmap icon (a | |
456 | picture of a gnu); @code{nil} specifies a text icon. | |
d25390d0 | 457 | |
bfe721d1 KH |
458 | @item icon-name |
459 | The name to use in the icon for this frame, when and if the icon | |
460 | appears. If this is @code{nil}, the frame's title is used. | |
461 | ||
d25390d0 | 462 | @item foreground-color |
969fe9b5 | 463 | The color to use for the image of a character. This is a string; the |
8241495d RS |
464 | window system defines the meaningful color names. Changing this |
465 | parameter is equivalent to changing the foreground color of the face | |
466 | @code{default} on the frame in question. | |
1911e6e5 | 467 | |
d25390d0 | 468 | @item background-color |
8241495d RS |
469 | The color to use for the background of characters. Changing this |
470 | parameter is equivalent to changing the foreground color of the face | |
471 | @code{default} on the frame in question. | |
1911e6e5 RS |
472 | |
473 | @item background-mode | |
474 | This parameter is either @code{dark} or @code{light}, according | |
475 | to whether the background color is a light one or a dark one. | |
476 | ||
d25390d0 | 477 | @item mouse-color |
8241495d RS |
478 | The color for the mouse pointer. Changing this parameter is equivalent |
479 | to changing the background color of face @code{mouse}. | |
d25390d0 RS |
480 | |
481 | @item cursor-color | |
7b32356b | 482 | The color for the cursor that shows point. Changing this parameter is |
8241495d | 483 | equivalent to changing the background color of face @code{cursor}. |
d25390d0 RS |
484 | |
485 | @item border-color | |
7b32356b | 486 | The color for the border of the frame. Changing this parameter is |
8241495d RS |
487 | equivalent to changing the background color of face @code{border}. |
488 | ||
7b32356b EZ |
489 | @item tty-color-mode |
490 | @cindex standard colors for character terminals | |
491 | This parameter overrides the terminal's color support as given by the | |
492 | system's terminal capabilities database in that this parameter's value | |
493 | specifies the color mode to use in terminal frames. The value can be | |
494 | either a symbol or a number. A number specifies the number of colors | |
495 | to use (and, indirectly, what commands to issue to produce each | |
496 | color). For example, @code{(tty-color-mode . 8)} forces Emacs to use | |
497 | the ANSI escape sequences for 8 standard text colors; and a value of | |
498 | -1 means Emacs should turn off color support. If the parameter's | |
499 | value is a symbol, that symbol is looked up in the alist | |
500 | @code{tty-color-mode-alist}, and if found, the associated number is | |
501 | used as the color support mode. | |
502 | ||
8241495d RS |
503 | @item scroll-bar-foreground |
504 | If non-@code{nil}, the color for the foreground of scroll bars. | |
505 | Changing this parameter is equivalent to setting the foreground color of | |
506 | face @code{scroll-bar}. | |
507 | ||
508 | @item scroll-bar-background | |
509 | If non-@code{nil}, the color for the background of scroll bars. | |
a3fbafe2 | 510 | Changing this parameter is equivalent to setting the background color of |
8241495d | 511 | face @code{scroll-bar}. |
d25390d0 | 512 | |
1911e6e5 RS |
513 | @item display-type |
514 | This parameter describes the range of possible colors that can be used | |
515 | in this frame. Its value is @code{color}, @code{grayscale} or | |
516 | @code{mono}. | |
517 | ||
d25390d0 | 518 | @item cursor-type |
1daccbf4 RS |
519 | How to display the cursor. Legitimate values are: |
520 | ||
521 | @table @code | |
522 | @item box | |
523 | Display a filled box. (This is the default.) | |
524 | @item hollow | |
525 | Display a hollow box. | |
526 | @item nil | |
527 | Don't display a cursor. | |
528 | @item bar | |
529 | Display a vertical bar between characters. | |
530 | @item (bar . @var{width}) | |
531 | Display a vertical bar @var{width} pixels wide between characters. | |
532 | @item hbar | |
533 | Display a horizontal bar. | |
534 | @item (bar . @var{width}) | |
535 | Display a horizontal bar @var{width} pixels high. | |
536 | @end table | |
d25390d0 | 537 | |
caae20c7 | 538 | @vindex cursor-type |
28932ac1 EZ |
539 | The buffer-local variable @code{cursor-type} overrides the value of |
540 | the @code{cursor-type} frame parameter, and can in addition have | |
541 | values @code{t} (use the cursor specified for the frame) and | |
542 | @code{nil} (don't display a cursor). | |
543 | ||
d25390d0 RS |
544 | @item border-width |
545 | The width in pixels of the window border. | |
546 | ||
547 | @item internal-border-width | |
548 | The distance in pixels between text and border. | |
549 | ||
550 | @item unsplittable | |
551 | If non-@code{nil}, this frame's window is never split automatically. | |
552 | ||
553 | @item visibility | |
554 | The state of visibility of the frame. There are three possibilities: | |
555 | @code{nil} for invisible, @code{t} for visible, and @code{icon} for | |
556 | iconified. @xref{Visibility of Frames}. | |
557 | ||
558 | @item menu-bar-lines | |
559 | The number of lines to allocate at the top of the frame for a menu bar. | |
0f6b12c9 RS |
560 | The default is 1. @xref{Menu Bar}. (In Emacs versions that use the X |
561 | toolkit, there is only one menu bar line; all that matters about the | |
562 | number you specify is whether it is greater than zero.) | |
d25390d0 | 563 | |
8241495d | 564 | @item screen-gamma |
7d817b83 | 565 | @cindex gamma correction |
3243b9f3 RS |
566 | If this is a number, Emacs performs ``gamma correction'' which adjusts |
567 | the brightness of all colors. The value should be the screen gamma of | |
568 | your display, a floating point number. | |
569 | ||
570 | Usual PC monitors have a screen gamma of 2.2, so color values in | |
571 | Emacs, and in X windows generally, are calibrated to display properly | |
572 | on a monitor with that gamma value. If you specify 2.2 for | |
573 | @code{screen-gamma}, that means no correction is needed. Other values | |
574 | request correction, designed to make the corrected colors appear on | |
575 | your screen they way they would have appeared without correction on an | |
576 | ordinary monitor with a gamma value of 2.2. | |
577 | ||
578 | If your monitor displays colors too light, you should specify a | |
579 | @code{screen-gamma} value smaller than 2.2. This requests correction | |
580 | that makes colors darker. A screen gamma value of 1.5 may give good | |
581 | results for LCD color displays. | |
8241495d RS |
582 | |
583 | @item tool-bar-lines | |
584 | The number of lines to use for the toolbar. A value of @code{nil} means | |
585 | don't display a tool bar. | |
586 | ||
7d817b83 DL |
587 | @item line-spacing |
588 | Additional space put below text lines in pixels (a positive integer). | |
589 | ||
a9f0a989 | 590 | @ignore |
d25390d0 RS |
591 | @item parent-id |
592 | @c ??? Not yet working. | |
593 | The X window number of the window that should be the parent of this one. | |
594 | Specifying this lets you create an Emacs window inside some other | |
595 | application's window. (It is not certain this will be implemented; try | |
596 | it and see if it works.) | |
a9f0a989 | 597 | @end ignore |
d25390d0 RS |
598 | @end table |
599 | ||
1daccbf4 RS |
600 | @defvar blink-cursor-alist |
601 | This variable specifies how to blink the cursor. Each element has the | |
602 | form @code{(@var{on-state} . @var{off-state})}. Whenever the cursor | |
603 | type equals @var{on-state} (comparing using @code{equal}), Emacs uses | |
604 | @var{off-state} to specify what the cursor looks like when it blinks | |
605 | ``off''. Both @var{on-state} and @var{off-state} should be suitable | |
606 | values for the @code{cursor-type} frame parameter. | |
607 | ||
608 | There are various defaults for how to blink each type of cursor, | |
609 | if the type is not mentioned as an @var{on-state} here. Changes | |
610 | in this variable do not take effect immediately, because the variable | |
611 | is examined only when you specify a cursor type for a frame. | |
612 | @end defvar | |
613 | ||
fb9b5ab7 | 614 | @node Size and Position |
d25390d0 | 615 | @subsection Frame Size And Position |
1911e6e5 RS |
616 | @cindex size of frame |
617 | @cindex screen size | |
618 | @cindex frame size | |
619 | @cindex resize frame | |
d25390d0 RS |
620 | |
621 | You can read or change the size and position of a frame using the | |
61cfa852 | 622 | frame parameters @code{left}, @code{top}, @code{height}, and |
bd998259 RS |
623 | @code{width}. Whatever geometry parameters you don't specify are chosen |
624 | by the window manager in its usual fashion. | |
d25390d0 | 625 | |
5df7058c EZ |
626 | Here are some special features for working with sizes and positions. |
627 | (For the precise meaning of ``selected frame'' used by these functions, | |
628 | see @ref{Input Focus}.) | |
d25390d0 RS |
629 | |
630 | @defun set-frame-position frame left top | |
bfe721d1 KH |
631 | This function sets the position of the top left corner of @var{frame} to |
632 | @var{left} and @var{top}. These arguments are measured in pixels, and | |
1911e6e5 RS |
633 | normally count from the top left corner of the screen. |
634 | ||
635 | Negative parameter values position the bottom edge of the window up from | |
636 | the bottom edge of the screen, or the right window edge to the left of | |
637 | the right edge of the screen. It would probably be better if the values | |
638 | were always counted from the left and top, so that negative arguments | |
639 | would position the frame partly off the top or left edge of the screen, | |
640 | but it seems inadvisable to change that now. | |
d25390d0 RS |
641 | @end defun |
642 | ||
643 | @defun frame-height &optional frame | |
644 | @defunx frame-width &optional frame | |
645 | These functions return the height and width of @var{frame}, measured in | |
1911e6e5 RS |
646 | lines and columns. If you don't supply @var{frame}, they use the |
647 | selected frame. | |
648 | @end defun | |
649 | ||
650 | @defun screen-height | |
651 | @defunx screen-width | |
652 | These functions are old aliases for @code{frame-height} and | |
653 | @code{frame-width}. When you are using a non-window terminal, the size | |
654 | of the frame is normally the same as the size of the terminal screen. | |
d25390d0 RS |
655 | @end defun |
656 | ||
657 | @defun frame-pixel-height &optional frame | |
658 | @defunx frame-pixel-width &optional frame | |
659 | These functions return the height and width of @var{frame}, measured in | |
660 | pixels. If you don't supply @var{frame}, they use the selected frame. | |
661 | @end defun | |
662 | ||
663 | @defun frame-char-height &optional frame | |
664 | @defunx frame-char-width &optional frame | |
61cfa852 RS |
665 | These functions return the height and width of a character in |
666 | @var{frame}, measured in pixels. The values depend on the choice of | |
667 | font. If you don't supply @var{frame}, these functions use the selected | |
668 | frame. | |
d25390d0 RS |
669 | @end defun |
670 | ||
671 | @defun set-frame-size frame cols rows | |
fb9b5ab7 RS |
672 | This function sets the size of @var{frame}, measured in characters; |
673 | @var{cols} and @var{rows} specify the new width and height. | |
d25390d0 | 674 | |
fb9b5ab7 RS |
675 | To set the size based on values measured in pixels, use |
676 | @code{frame-char-height} and @code{frame-char-width} to convert | |
677 | them to units of characters. | |
d25390d0 RS |
678 | @end defun |
679 | ||
1911e6e5 RS |
680 | @defun set-frame-height frame lines &optional pretend |
681 | This function resizes @var{frame} to a height of @var{lines} lines. The | |
682 | sizes of existing windows in @var{frame} are altered proportionally to | |
683 | fit. | |
684 | ||
685 | If @var{pretend} is non-@code{nil}, then Emacs displays @var{lines} | |
686 | lines of output in @var{frame}, but does not change its value for the | |
687 | actual height of the frame. This is only useful for a terminal frame. | |
688 | Using a smaller height than the terminal actually implements may be | |
689 | useful to reproduce behavior observed on a smaller screen, or if the | |
690 | terminal malfunctions when using its whole screen. Setting the frame | |
691 | height ``for real'' does not always work, because knowing the correct | |
692 | actual size may be necessary for correct cursor positioning on a | |
693 | terminal frame. | |
694 | @end defun | |
695 | ||
696 | @defun set-frame-width frame width &optional pretend | |
697 | This function sets the width of @var{frame}, measured in characters. | |
698 | The argument @var{pretend} has the same meaning as in | |
699 | @code{set-frame-height}. | |
700 | @end defun | |
701 | ||
702 | @findex set-screen-height | |
703 | @findex set-screen-width | |
ebc6903b RS |
704 | The older functions @code{set-screen-height} and |
705 | @code{set-screen-width} were used to specify the height and width of the | |
706 | screen, in Emacs versions that did not support multiple frames. They | |
707 | are semi-obsolete, but still work; they apply to the selected frame. | |
d25390d0 RS |
708 | |
709 | @defun x-parse-geometry geom | |
710 | @cindex geometry specification | |
1911e6e5 | 711 | The function @code{x-parse-geometry} converts a standard X window |
61cfa852 | 712 | geometry string to an alist that you can use as part of the argument to |
d25390d0 RS |
713 | @code{make-frame}. |
714 | ||
715 | The alist describes which parameters were specified in @var{geom}, and | |
716 | gives the values specified for them. Each element looks like | |
717 | @code{(@var{parameter} . @var{value})}. The possible @var{parameter} | |
718 | values are @code{left}, @code{top}, @code{width}, and @code{height}. | |
719 | ||
22697dac KH |
720 | For the size parameters, the value must be an integer. The position |
721 | parameter names @code{left} and @code{top} are not totally accurate, | |
722 | because some values indicate the position of the right or bottom edges | |
723 | instead. These are the @var{value} possibilities for the position | |
724 | parameters: | |
725 | ||
726 | @table @asis | |
727 | @item an integer | |
728 | A positive integer relates the left edge or top edge of the window to | |
729 | the left or top edge of the screen. A negative integer relates the | |
730 | right or bottom edge of the window to the right or bottom edge of the | |
731 | screen. | |
732 | ||
bfe721d1 | 733 | @item @code{(+ @var{position})} |
22697dac KH |
734 | This specifies the position of the left or top edge of the window |
735 | relative to the left or top edge of the screen. The integer | |
736 | @var{position} may be positive or negative; a negative value specifies a | |
737 | position outside the screen. | |
738 | ||
bfe721d1 | 739 | @item @code{(- @var{position})} |
22697dac KH |
740 | This specifies the position of the right or bottom edge of the window |
741 | relative to the right or bottom edge of the screen. The integer | |
742 | @var{position} may be positive or negative; a negative value specifies a | |
743 | position outside the screen. | |
744 | @end table | |
745 | ||
746 | Here is an example: | |
747 | ||
bfe721d1 | 748 | @example |
d25390d0 | 749 | (x-parse-geometry "35x70+0-0") |
1911e6e5 RS |
750 | @result{} ((height . 70) (width . 35) |
751 | (top - 0) (left . 0)) | |
bfe721d1 | 752 | @end example |
d25390d0 RS |
753 | @end defun |
754 | ||
22697dac KH |
755 | @node Frame Titles |
756 | @section Frame Titles | |
757 | ||
969fe9b5 RS |
758 | Every frame has a @code{name} parameter; this serves as the default |
759 | for the frame title which window systems typically display at the top of | |
760 | the frame. You can specify a name explicitly by setting the @code{name} | |
761 | frame property. | |
22697dac | 762 | |
969fe9b5 RS |
763 | Normally you don't specify the name explicitly, and Emacs computes the |
764 | frame name automatically based on a template stored in the variable | |
765 | @code{frame-title-format}. Emacs recomputes the name each time the | |
766 | frame is redisplayed. | |
22697dac KH |
767 | |
768 | @defvar frame-title-format | |
969fe9b5 RS |
769 | This variable specifies how to compute a name for a frame when you have |
770 | not explicitly specified one. The variable's value is actually a mode | |
771 | line construct, just like @code{mode-line-format}. @xref{Mode Line | |
772 | Data}. | |
22697dac KH |
773 | @end defvar |
774 | ||
775 | @defvar icon-title-format | |
969fe9b5 | 776 | This variable specifies how to compute the name for an iconified frame, |
22697dac KH |
777 | when you have not explicitly specified the frame title. This title |
778 | appears in the icon itself. | |
779 | @end defvar | |
780 | ||
781 | @defvar multiple-frames | |
782 | This variable is set automatically by Emacs. Its value is @code{t} when | |
783 | there are two or more frames (not counting minibuffer-only frames or | |
784 | invisible frames). The default value of @code{frame-title-format} uses | |
785 | @code{multiple-frames} so as to put the buffer name in the frame title | |
786 | only when there is more than one frame. | |
22697dac KH |
787 | @end defvar |
788 | ||
d25390d0 RS |
789 | @node Deleting Frames |
790 | @section Deleting Frames | |
791 | @cindex deletion of frames | |
792 | ||
793 | Frames remain potentially visible until you explicitly @dfn{delete} | |
794 | them. A deleted frame cannot appear on the screen, but continues to | |
795 | exist as a Lisp object until there are no references to it. There is no | |
796 | way to cancel the deletion of a frame aside from restoring a saved frame | |
797 | configuration (@pxref{Frame Configurations}); this is similar to the | |
798 | way windows behave. | |
799 | ||
94886883 | 800 | @deffn Command delete-frame &optional frame force |
82d10c89 DL |
801 | @vindex delete-frame-hook |
802 | This function deletes the frame @var{frame} after running the hook | |
803 | @code{delete-frame-hook}. By default, @var{frame} is the selected | |
804 | frame. | |
94886883 GM |
805 | |
806 | A frame cannot be deleted if its minibuffer is used by other frames. | |
807 | Normally, you cannot delete a frame if all other frames are invisible, | |
808 | but if the @var{force} is non-@code{nil}, then you are allowed to do so. | |
d25390d0 RS |
809 | @end deffn |
810 | ||
811 | @defun frame-live-p frame | |
812 | The function @code{frame-live-p} returns non-@code{nil} if the frame | |
813 | @var{frame} has not been deleted. | |
814 | @end defun | |
815 | ||
22697dac | 816 | Some window managers provide a command to delete a window. These work |
eaac2be1 | 817 | by sending a special message to the program that operates the window. |
22697dac KH |
818 | When Emacs gets one of these commands, it generates a |
819 | @code{delete-frame} event, whose normal definition is a command that | |
820 | calls the function @code{delete-frame}. @xref{Misc Events}. | |
821 | ||
d25390d0 RS |
822 | @node Finding All Frames |
823 | @section Finding All Frames | |
824 | ||
825 | @defun frame-list | |
826 | The function @code{frame-list} returns a list of all the frames that | |
827 | have not been deleted. It is analogous to @code{buffer-list} for | |
3d7f0a34 EZ |
828 | buffers, and includes frames on all terminals. The list that you get is |
829 | newly created, so modifying the list doesn't have any effect on the | |
830 | internals of Emacs. | |
d25390d0 RS |
831 | @end defun |
832 | ||
833 | @defun visible-frame-list | |
834 | This function returns a list of just the currently visible frames. | |
22697dac KH |
835 | @xref{Visibility of Frames}. (Terminal frames always count as |
836 | ``visible'', even though only the selected one is actually displayed.) | |
d25390d0 RS |
837 | @end defun |
838 | ||
839 | @defun next-frame &optional frame minibuf | |
840 | The function @code{next-frame} lets you cycle conveniently through all | |
3d7f0a34 EZ |
841 | the frames on the current display from an arbitrary starting point. It |
842 | returns the ``next'' frame after @var{frame} in the cycle. If | |
843 | @var{frame} is omitted or @code{nil}, it defaults to the selected frame | |
844 | (@pxref{Input Focus}). | |
d25390d0 RS |
845 | |
846 | The second argument, @var{minibuf}, says which frames to consider: | |
847 | ||
848 | @table @asis | |
849 | @item @code{nil} | |
850 | Exclude minibuffer-only frames. | |
851 | @item @code{visible} | |
852 | Consider all visible frames. | |
bfe721d1 KH |
853 | @item 0 |
854 | Consider all visible or iconified frames. | |
d25390d0 RS |
855 | @item a window |
856 | Consider only the frames using that particular window as their | |
857 | minibuffer. | |
858 | @item anything else | |
859 | Consider all frames. | |
860 | @end table | |
861 | @end defun | |
862 | ||
863 | @defun previous-frame &optional frame minibuf | |
864 | Like @code{next-frame}, but cycles through all frames in the opposite | |
865 | direction. | |
866 | @end defun | |
867 | ||
bfe721d1 KH |
868 | See also @code{next-window} and @code{previous-window}, in @ref{Cyclic |
869 | Window Ordering}. | |
870 | ||
d25390d0 RS |
871 | @node Frames and Windows |
872 | @section Frames and Windows | |
873 | ||
fb9b5ab7 RS |
874 | Each window is part of one and only one frame; you can get the frame |
875 | with @code{window-frame}. | |
d25390d0 RS |
876 | |
877 | @defun window-frame window | |
878 | This function returns the frame that @var{window} is on. | |
fb9b5ab7 RS |
879 | @end defun |
880 | ||
881 | All the non-minibuffer windows in a frame are arranged in a cyclic | |
882 | order. The order runs from the frame's top window, which is at the | |
883 | upper left corner, down and to the right, until it reaches the window at | |
884 | the lower right corner (always the minibuffer window, if the frame has | |
f9f59935 | 885 | one), and then it moves back to the top. @xref{Cyclic Window Ordering}. |
fb9b5ab7 | 886 | |
8241495d | 887 | @defun frame-first-window frame |
fb9b5ab7 | 888 | This returns the topmost, leftmost window of frame @var{frame}. |
d25390d0 RS |
889 | @end defun |
890 | ||
891 | At any time, exactly one window on any frame is @dfn{selected within the | |
892 | frame}. The significance of this designation is that selecting the | |
893 | frame also selects this window. You can get the frame's current | |
894 | selected window with @code{frame-selected-window}. | |
895 | ||
896 | @defun frame-selected-window frame | |
61cfa852 | 897 | This function returns the window on @var{frame} that is selected within |
d25390d0 RS |
898 | @var{frame}. |
899 | @end defun | |
900 | ||
969fe9b5 | 901 | Conversely, selecting a window for Emacs with @code{select-window} also |
d25390d0 RS |
902 | makes that window selected within its frame. @xref{Selecting Windows}. |
903 | ||
969fe9b5 RS |
904 | Another function that (usually) returns one of the windows in a given |
905 | frame is @code{minibuffer-window}. @xref{Minibuffer Misc}. | |
bfe721d1 | 906 | |
d25390d0 RS |
907 | @node Minibuffers and Frames |
908 | @section Minibuffers and Frames | |
909 | ||
910 | Normally, each frame has its own minibuffer window at the bottom, which | |
911 | is used whenever that frame is selected. If the frame has a minibuffer, | |
912 | you can get it with @code{minibuffer-window} (@pxref{Minibuffer Misc}). | |
913 | ||
914 | However, you can also create a frame with no minibuffer. Such a frame | |
915 | must use the minibuffer window of some other frame. When you create the | |
bfe721d1 KH |
916 | frame, you can specify explicitly the minibuffer window to use (in some |
917 | other frame). If you don't, then the minibuffer is found in the frame | |
918 | which is the value of the variable @code{default-minibuffer-frame}. Its | |
919 | value should be a frame that does have a minibuffer. | |
d25390d0 RS |
920 | |
921 | If you use a minibuffer-only frame, you might want that frame to raise | |
922 | when you enter the minibuffer. If so, set the variable | |
923 | @code{minibuffer-auto-raise} to @code{t}. @xref{Raising and Lowering}. | |
924 | ||
22697dac KH |
925 | @defvar default-minibuffer-frame |
926 | This variable specifies the frame to use for the minibuffer window, by | |
bfe721d1 | 927 | default. It is always local to the current terminal and cannot be |
22697dac KH |
928 | buffer-local. @xref{Multiple Displays}. |
929 | @end defvar | |
930 | ||
d25390d0 RS |
931 | @node Input Focus |
932 | @section Input Focus | |
933 | @cindex input focus | |
934 | @cindex selected frame | |
935 | ||
936 | At any time, one frame in Emacs is the @dfn{selected frame}. The selected | |
937 | window always resides on the selected frame. | |
938 | ||
5df7058c EZ |
939 | When Emacs displays its frames on several terminals (@pxref{Multiple |
940 | Displays}), each terminal has its own selected frame. But only one of | |
941 | these is ``@emph{the} selected frame'': it's the frame that belongs to | |
942 | the terminal from which the most recent input came. That is, when Emacs | |
943 | runs a command that came from a certain terminal, the selected frame is | |
944 | the one of that terminal. Since Emacs runs only a single command at any | |
945 | given time, it needs to consider only one selected frame at a time; this | |
946 | frame is what we call @dfn{the selected frame} in this manual. The | |
947 | display on which the selected frame is displayed is the @dfn{selected | |
948 | frame's display}. | |
949 | ||
d25390d0 RS |
950 | @defun selected-frame |
951 | This function returns the selected frame. | |
952 | @end defun | |
953 | ||
969fe9b5 RS |
954 | Some window systems and window managers direct keyboard input to the |
955 | window object that the mouse is in; others require explicit clicks or | |
956 | commands to @dfn{shift the focus} to various window objects. Either | |
957 | way, Emacs automatically keeps track of which frame has the focus. | |
d25390d0 | 958 | |
969fe9b5 RS |
959 | Lisp programs can also switch frames ``temporarily'' by calling the |
960 | function @code{select-frame}. This does not alter the window system's | |
961 | concept of focus; rather, it escapes from the window manager's control | |
962 | until that control is somehow reasserted. | |
d25390d0 | 963 | |
969fe9b5 RS |
964 | When using a text-only terminal, only the selected terminal frame is |
965 | actually displayed on the terminal. @code{switch-frame} is the only way | |
966 | to switch frames, and the change lasts until overridden by a subsequent | |
967 | call to @code{switch-frame}. Each terminal screen except for the | |
968 | initial one has a number, and the number of the selected frame appears | |
1911e6e5 | 969 | in the mode line before the buffer name (@pxref{Mode Line Variables}). |
22697dac | 970 | |
d25390d0 RS |
971 | @c ??? This is not yet implemented properly. |
972 | @defun select-frame frame | |
973 | This function selects frame @var{frame}, temporarily disregarding the | |
22697dac KH |
974 | focus of the X server if any. The selection of @var{frame} lasts until |
975 | the next time the user does something to select a different frame, or | |
5df7058c EZ |
976 | until the next time this function is called. The specified @var{frame} |
977 | becomes the selected frame, as explained above, and the terminal that | |
978 | @var{frame} is on becomes the selected terminal. | |
979 | ||
980 | In general, you should never use @code{select-frame} in a way that could | |
981 | switch to a different terminal without switching back when you're done. | |
d25390d0 RS |
982 | @end defun |
983 | ||
969fe9b5 RS |
984 | Emacs cooperates with the window system by arranging to select frames as |
985 | the server and window manager request. It does so by generating a | |
986 | special kind of input event, called a @dfn{focus} event, when | |
987 | appropriate. The command loop handles a focus event by calling | |
1a426e9b | 988 | @code{handle-switch-frame}. @xref{Focus Events}. |
d25390d0 RS |
989 | |
990 | @deffn Command handle-switch-frame frame | |
991 | This function handles a focus event by selecting frame @var{frame}. | |
992 | ||
993 | Focus events normally do their job by invoking this command. | |
994 | Don't call it for any other reason. | |
995 | @end deffn | |
996 | ||
997 | @defun redirect-frame-focus frame focus-frame | |
998 | This function redirects focus from @var{frame} to @var{focus-frame}. | |
f9f59935 RS |
999 | This means that @var{focus-frame} will receive subsequent keystrokes and |
1000 | events intended for @var{frame}. After such an event, the value of | |
d25390d0 RS |
1001 | @code{last-event-frame} will be @var{focus-frame}. Also, switch-frame |
1002 | events specifying @var{frame} will instead select @var{focus-frame}. | |
1003 | ||
1004 | If @var{focus-frame} is @code{nil}, that cancels any existing | |
1005 | redirection for @var{frame}, which therefore once again receives its own | |
1006 | events. | |
1007 | ||
1008 | One use of focus redirection is for frames that don't have minibuffers. | |
1009 | These frames use minibuffers on other frames. Activating a minibuffer | |
1010 | on another frame redirects focus to that frame. This puts the focus on | |
1011 | the minibuffer's frame, where it belongs, even though the mouse remains | |
61cfa852 | 1012 | in the frame that activated the minibuffer. |
d25390d0 RS |
1013 | |
1014 | Selecting a frame can also change focus redirections. Selecting frame | |
1015 | @code{bar}, when @code{foo} had been selected, changes any redirections | |
1016 | pointing to @code{foo} so that they point to @code{bar} instead. This | |
1017 | allows focus redirection to work properly when the user switches from | |
1018 | one frame to another using @code{select-window}. | |
1019 | ||
1020 | This means that a frame whose focus is redirected to itself is treated | |
1021 | differently from a frame whose focus is not redirected. | |
1022 | @code{select-frame} affects the former but not the latter. | |
1023 | ||
1024 | The redirection lasts until @code{redirect-frame-focus} is called to | |
1025 | change it. | |
1026 | @end defun | |
1027 | ||
969fe9b5 RS |
1028 | @defopt focus-follows-mouse |
1029 | This option is how you inform Emacs whether the window manager transfers | |
1030 | focus when the user moves the mouse. Non-@code{nil} says that it does. | |
1031 | When this is so, the command @code{other-frame} moves the mouse to a | |
1032 | position consistent with the new selected frame. | |
1033 | @end defopt | |
1034 | ||
d25390d0 RS |
1035 | @node Visibility of Frames |
1036 | @section Visibility of Frames | |
1037 | @cindex visible frame | |
1038 | @cindex invisible frame | |
1039 | @cindex iconified frame | |
1040 | @cindex frame visibility | |
1041 | ||
969fe9b5 | 1042 | A window frame may be @dfn{visible}, @dfn{invisible}, or |
22697dac KH |
1043 | @dfn{iconified}. If it is visible, you can see its contents. If it is |
1044 | iconified, the frame's contents do not appear on the screen, but an icon | |
1045 | does. If the frame is invisible, it doesn't show on the screen, not | |
1046 | even as an icon. | |
1047 | ||
1048 | Visibility is meaningless for terminal frames, since only the selected | |
1049 | one is actually displayed in any case. | |
d25390d0 RS |
1050 | |
1051 | @deffn Command make-frame-visible &optional frame | |
1052 | This function makes frame @var{frame} visible. If you omit @var{frame}, | |
1053 | it makes the selected frame visible. | |
1054 | @end deffn | |
1055 | ||
1056 | @deffn Command make-frame-invisible &optional frame | |
1057 | This function makes frame @var{frame} invisible. If you omit | |
1058 | @var{frame}, it makes the selected frame invisible. | |
1059 | @end deffn | |
1060 | ||
1061 | @deffn Command iconify-frame &optional frame | |
1062 | This function iconifies frame @var{frame}. If you omit @var{frame}, it | |
1063 | iconifies the selected frame. | |
1064 | @end deffn | |
1065 | ||
1066 | @defun frame-visible-p frame | |
1067 | This returns the visibility status of frame @var{frame}. The value is | |
1068 | @code{t} if @var{frame} is visible, @code{nil} if it is invisible, and | |
1069 | @code{icon} if it is iconified. | |
1070 | @end defun | |
1071 | ||
1072 | The visibility status of a frame is also available as a frame | |
969fe9b5 | 1073 | parameter. You can read or change it as such. @xref{Window Frame |
d25390d0 RS |
1074 | Parameters}. |
1075 | ||
22697dac KH |
1076 | The user can iconify and deiconify frames with the window manager. |
1077 | This happens below the level at which Emacs can exert any control, but | |
1078 | Emacs does provide events that you can use to keep track of such | |
1079 | changes. @xref{Misc Events}. | |
1080 | ||
d25390d0 RS |
1081 | @node Raising and Lowering |
1082 | @section Raising and Lowering Frames | |
1083 | ||
969fe9b5 | 1084 | Most window systems use a desktop metaphor. Part of this metaphor is |
d25390d0 RS |
1085 | the idea that windows are stacked in a notional third dimension |
1086 | perpendicular to the screen surface, and thus ordered from ``highest'' | |
969fe9b5 RS |
1087 | to ``lowest''. Where two windows overlap, the one higher up covers |
1088 | the one underneath. Even a window at the bottom of the stack can be | |
1089 | seen if no other window overlaps it. | |
d25390d0 RS |
1090 | |
1091 | @cindex raising a frame | |
1092 | @cindex lowering a frame | |
969fe9b5 RS |
1093 | A window's place in this ordering is not fixed; in fact, users tend |
1094 | to change the order frequently. @dfn{Raising} a window means moving | |
1095 | it ``up'', to the top of the stack. @dfn{Lowering} a window means | |
f9f59935 | 1096 | moving it to the bottom of the stack. This motion is in the notional |
969fe9b5 | 1097 | third dimension only, and does not change the position of the window |
f9f59935 | 1098 | on the screen. |
d25390d0 | 1099 | |
969fe9b5 | 1100 | You can raise and lower Emacs frame Windows with these functions: |
d25390d0 | 1101 | |
a9f0a989 RS |
1102 | @deffn Command raise-frame &optional frame |
1103 | This function raises frame @var{frame} (default, the selected frame). | |
22697dac | 1104 | @end deffn |
d25390d0 | 1105 | |
a9f0a989 RS |
1106 | @deffn Command lower-frame &optional frame |
1107 | This function lowers frame @var{frame} (default, the selected frame). | |
22697dac | 1108 | @end deffn |
d25390d0 RS |
1109 | |
1110 | @defopt minibuffer-auto-raise | |
1111 | If this is non-@code{nil}, activation of the minibuffer raises the frame | |
1112 | that the minibuffer window is in. | |
1113 | @end defopt | |
1114 | ||
1115 | You can also enable auto-raise (raising automatically when a frame is | |
1116 | selected) or auto-lower (lowering automatically when it is deselected) | |
969fe9b5 | 1117 | for any frame using frame parameters. @xref{Window Frame Parameters}. |
d25390d0 RS |
1118 | |
1119 | @node Frame Configurations | |
1120 | @section Frame Configurations | |
1121 | @cindex frame configuration | |
1122 | ||
1123 | A @dfn{frame configuration} records the current arrangement of frames, | |
1124 | all their properties, and the window configuration of each one. | |
969fe9b5 | 1125 | (@xref{Window Configurations}.) |
d25390d0 RS |
1126 | |
1127 | @defun current-frame-configuration | |
61cfa852 | 1128 | This function returns a frame configuration list that describes |
d25390d0 RS |
1129 | the current arrangement of frames and their contents. |
1130 | @end defun | |
1131 | ||
94886883 | 1132 | @defun set-frame-configuration configuration &optional nodelete |
d25390d0 RS |
1133 | This function restores the state of frames described in |
1134 | @var{configuration}. | |
94886883 GM |
1135 | |
1136 | Ordinarily, this function deletes all existing frames not listed in | |
1137 | @var{configuration}. But if @var{nodelete} is non-@code{nil}, the | |
1138 | unwanted frames are iconified instead. | |
d25390d0 RS |
1139 | @end defun |
1140 | ||
1141 | @node Mouse Tracking | |
1142 | @section Mouse Tracking | |
1143 | @cindex mouse tracking | |
1144 | @cindex tracking the mouse | |
1145 | ||
61cfa852 | 1146 | Sometimes it is useful to @dfn{track} the mouse, which means to display |
d25390d0 RS |
1147 | something to indicate where the mouse is and move the indicator as the |
1148 | mouse moves. For efficient mouse tracking, you need a way to wait until | |
1149 | the mouse actually moves. | |
1150 | ||
1151 | The convenient way to track the mouse is to ask for events to represent | |
1152 | mouse motion. Then you can wait for motion by waiting for an event. In | |
1153 | addition, you can easily handle any other sorts of events that may | |
1154 | occur. That is useful, because normally you don't want to track the | |
1155 | mouse forever---only until some other event, such as the release of a | |
1156 | button. | |
1157 | ||
1158 | @defspec track-mouse body@dots{} | |
969fe9b5 RS |
1159 | This special form executes @var{body}, with generation of mouse motion |
1160 | events enabled. Typically @var{body} would use @code{read-event} to | |
1161 | read the motion events and modify the display accordingly. @xref{Motion | |
1162 | Events}, for the format of mouse motion events. | |
d25390d0 RS |
1163 | |
1164 | The value of @code{track-mouse} is that of the last form in @var{body}. | |
969fe9b5 RS |
1165 | You should design @var{body} to return when it sees the up-event that |
1166 | indicates the release of the button, or whatever kind of event means | |
1167 | it is time to stop tracking. | |
d25390d0 RS |
1168 | @end defspec |
1169 | ||
1170 | The usual purpose of tracking mouse motion is to indicate on the screen | |
1171 | the consequences of pushing or releasing a button at the current | |
1172 | position. | |
1173 | ||
bfe721d1 KH |
1174 | In many cases, you can avoid the need to track the mouse by using |
1175 | the @code{mouse-face} text property (@pxref{Special Properties}). | |
1176 | That works at a much lower level and runs more smoothly than | |
1177 | Lisp-level mouse tracking. | |
1178 | ||
d25390d0 RS |
1179 | @ignore |
1180 | @c These are not implemented yet. | |
1181 | ||
1182 | These functions change the screen appearance instantaneously. The | |
1183 | effect is transient, only until the next ordinary Emacs redisplay. That | |
969fe9b5 | 1184 | is OK for mouse tracking, since it doesn't make sense for mouse tracking |
d25390d0 RS |
1185 | to change the text, and the body of @code{track-mouse} normally reads |
1186 | the events itself and does not do redisplay. | |
1187 | ||
1188 | @defun x-contour-region window beg end | |
1189 | This function draws lines to make a box around the text from @var{beg} | |
1190 | to @var{end}, in window @var{window}. | |
1191 | @end defun | |
1192 | ||
1193 | @defun x-uncontour-region window beg end | |
1194 | This function erases the lines that would make a box around the text | |
1195 | from @var{beg} to @var{end}, in window @var{window}. Use it to remove | |
1196 | a contour that you previously made by calling @code{x-contour-region}. | |
1197 | @end defun | |
1198 | ||
1199 | @defun x-draw-rectangle frame left top right bottom | |
1200 | This function draws a hollow rectangle on frame @var{frame} with the | |
1201 | specified edge coordinates, all measured in pixels from the inside top | |
1202 | left corner. It uses the cursor color, the one used for indicating the | |
1203 | location of point. | |
1204 | @end defun | |
1205 | ||
1206 | @defun x-erase-rectangle frame left top right bottom | |
1207 | This function erases a hollow rectangle on frame @var{frame} with the | |
1208 | specified edge coordinates, all measured in pixels from the inside top | |
1209 | left corner. Erasure means redrawing the text and background that | |
1210 | normally belong in the specified rectangle. | |
1211 | @end defun | |
1212 | @end ignore | |
1213 | ||
1214 | @node Mouse Position | |
1215 | @section Mouse Position | |
1216 | @cindex mouse position | |
1217 | @cindex position of mouse | |
1218 | ||
1219 | The functions @code{mouse-position} and @code{set-mouse-position} | |
1220 | give access to the current position of the mouse. | |
1221 | ||
1222 | @defun mouse-position | |
1223 | This function returns a description of the position of the mouse. The | |
1224 | value looks like @code{(@var{frame} @var{x} . @var{y})}, where @var{x} | |
fb9b5ab7 RS |
1225 | and @var{y} are integers giving the position in characters relative to |
1226 | the top left corner of the inside of @var{frame}. | |
d25390d0 RS |
1227 | @end defun |
1228 | ||
28932ac1 | 1229 | @defvar mouse-position-function |
caae20c7 RS |
1230 | If non-@code{nil}, the value of this variable is a function for |
1231 | @code{mouse-position} to call. @code{mouse-position} calls this | |
1232 | function just before returning, with its normal return value as the | |
1233 | sole argument, and it returns whatever this function returns to it. | |
1234 | ||
1235 | This abnormal hook exists for the benefit of packages like | |
1236 | @file{xt-mouse.el} that need to do mouse handling at the Lisp level. | |
28932ac1 EZ |
1237 | @end defvar |
1238 | ||
d25390d0 RS |
1239 | @defun set-mouse-position frame x y |
1240 | This function @dfn{warps the mouse} to position @var{x}, @var{y} in | |
1241 | frame @var{frame}. The arguments @var{x} and @var{y} are integers, | |
fb9b5ab7 | 1242 | giving the position in characters relative to the top left corner of the |
a9f0a989 RS |
1243 | inside of @var{frame}. If @var{frame} is not visible, this function |
1244 | does nothing. The return value is not significant. | |
fb9b5ab7 | 1245 | @end defun |
d25390d0 | 1246 | |
fb9b5ab7 RS |
1247 | @defun mouse-pixel-position |
1248 | This function is like @code{mouse-position} except that it returns | |
1249 | coordinates in units of pixels rather than units of characters. | |
1250 | @end defun | |
1251 | ||
1252 | @defun set-mouse-pixel-position frame x y | |
1253 | This function warps the mouse like @code{set-mouse-position} except that | |
1254 | @var{x} and @var{y} are in units of pixels rather than units of | |
1255 | characters. These coordinates are not required to be within the frame. | |
a9f0a989 RS |
1256 | |
1257 | If @var{frame} is not visible, this function does nothing. The return | |
1258 | value is not significant. | |
d25390d0 RS |
1259 | @end defun |
1260 | ||
1261 | @need 3000 | |
1262 | ||
1263 | @node Pop-Up Menus | |
1264 | @section Pop-Up Menus | |
1265 | ||
969fe9b5 RS |
1266 | When using a window system, a Lisp program can pop up a menu so that |
1267 | the user can choose an alternative with the mouse. | |
22697dac | 1268 | |
d25390d0 RS |
1269 | @defun x-popup-menu position menu |
1270 | This function displays a pop-up menu and returns an indication of | |
1271 | what selection the user makes. | |
1272 | ||
1273 | The argument @var{position} specifies where on the screen to put the | |
1274 | menu. It can be either a mouse button event (which says to put the menu | |
1275 | where the user actuated the button) or a list of this form: | |
1276 | ||
1277 | @example | |
1278 | ((@var{xoffset} @var{yoffset}) @var{window}) | |
1279 | @end example | |
1280 | ||
1281 | @noindent | |
fb9b5ab7 RS |
1282 | where @var{xoffset} and @var{yoffset} are coordinates, measured in |
1283 | pixels, counting from the top left corner of @var{window}'s frame. | |
d25390d0 RS |
1284 | |
1285 | If @var{position} is @code{t}, it means to use the current mouse | |
1286 | position. If @var{position} is @code{nil}, it means to precompute the | |
1287 | key binding equivalents for the keymaps specified in @var{menu}, | |
1288 | without actually displaying or popping up the menu. | |
1289 | ||
1290 | The argument @var{menu} says what to display in the menu. It can be a | |
1291 | keymap or a list of keymaps (@pxref{Menu Keymaps}). Alternatively, it | |
1292 | can have the following form: | |
1293 | ||
1294 | @example | |
1295 | (@var{title} @var{pane1} @var{pane2}...) | |
1296 | @end example | |
1297 | ||
1298 | @noindent | |
1299 | where each pane is a list of form | |
1300 | ||
1301 | @example | |
bfe721d1 | 1302 | (@var{title} (@var{line} . @var{item})...) |
d25390d0 RS |
1303 | @end example |
1304 | ||
1305 | Each @var{line} should be a string, and each @var{item} should be the | |
1306 | value to return if that @var{line} is chosen. | |
1307 | @end defun | |
1308 | ||
f9f59935 RS |
1309 | @strong{Usage note:} Don't use @code{x-popup-menu} to display a menu |
1310 | if you could do the job with a prefix key defined with a menu keymap. | |
1311 | If you use a menu keymap to implement a menu, @kbd{C-h c} and @kbd{C-h | |
1312 | a} can see the individual items in that menu and provide help for them. | |
1313 | If instead you implement the menu by defining a command that calls | |
1314 | @code{x-popup-menu}, the help facilities cannot know what happens inside | |
1315 | that command, so they cannot give any help for the menu's items. | |
2368fc6f RS |
1316 | |
1317 | The menu bar mechanism, which lets you switch between submenus by | |
1318 | moving the mouse, cannot look within the definition of a command to see | |
1319 | that it calls @code{x-popup-menu}. Therefore, if you try to implement a | |
1320 | submenu using @code{x-popup-menu}, it cannot work with the menu bar in | |
1321 | an integrated fashion. This is why all menu bar submenus are | |
1322 | implemented with menu keymaps within the parent menu, and never with | |
1323 | @code{x-popup-menu}. @xref{Menu Bar}, | |
1324 | ||
1325 | If you want a menu bar submenu to have contents that vary, you should | |
1326 | still use a menu keymap to implement it. To make the contents vary, add | |
1327 | a hook function to @code{menu-bar-update-hook} to update the contents of | |
1328 | the menu keymap as necessary. | |
d25390d0 RS |
1329 | |
1330 | @node Dialog Boxes | |
1331 | @section Dialog Boxes | |
1332 | @cindex dialog boxes | |
1333 | ||
969fe9b5 RS |
1334 | A dialog box is a variant of a pop-up menu---it looks a little |
1335 | different, it always appears in the center of a frame, and it has just | |
1336 | one level and one pane. The main use of dialog boxes is for asking | |
1337 | questions that the user can answer with ``yes'', ``no'', and a few other | |
1338 | alternatives. The functions @code{y-or-n-p} and @code{yes-or-no-p} use | |
1339 | dialog boxes instead of the keyboard, when called from commands invoked | |
1340 | by mouse clicks. | |
d25390d0 RS |
1341 | |
1342 | @defun x-popup-dialog position contents | |
1343 | This function displays a pop-up dialog box and returns an indication of | |
1344 | what selection the user makes. The argument @var{contents} specifies | |
1345 | the alternatives to offer; it has this format: | |
1346 | ||
1347 | @example | |
fb9b5ab7 | 1348 | (@var{title} (@var{string} . @var{value})@dots{}) |
d25390d0 RS |
1349 | @end example |
1350 | ||
1351 | @noindent | |
1352 | which looks like the list that specifies a single pane for | |
1353 | @code{x-popup-menu}. | |
1354 | ||
fb9b5ab7 RS |
1355 | The return value is @var{value} from the chosen alternative. |
1356 | ||
1357 | An element of the list may be just a string instead of a cons cell | |
1358 | @code{(@var{string} . @var{value})}. That makes a box that cannot | |
1359 | be selected. | |
1360 | ||
1361 | If @code{nil} appears in the list, it separates the left-hand items from | |
1362 | the right-hand items; items that precede the @code{nil} appear on the | |
1363 | left, and items that follow the @code{nil} appear on the right. If you | |
1364 | don't include a @code{nil} in the list, then approximately half the | |
1365 | items appear on each side. | |
1366 | ||
d25390d0 RS |
1367 | Dialog boxes always appear in the center of a frame; the argument |
1368 | @var{position} specifies which frame. The possible values are as in | |
1369 | @code{x-popup-menu}, but the precise coordinates don't matter; only the | |
1370 | frame matters. | |
fb9b5ab7 | 1371 | |
969fe9b5 RS |
1372 | In some configurations, Emacs cannot display a real dialog box; so |
1373 | instead it displays the same items in a pop-up menu in the center of the | |
1374 | frame. | |
d25390d0 RS |
1375 | @end defun |
1376 | ||
bd998259 RS |
1377 | @node Pointer Shapes |
1378 | @section Pointer Shapes | |
1379 | @cindex pointer shape | |
1380 | @cindex mouse pointer shape | |
1381 | ||
22697dac | 1382 | These variables specify which shape to use for the mouse pointer in |
969fe9b5 | 1383 | various situations, when using the X Window System: |
bd998259 RS |
1384 | |
1385 | @table @code | |
1386 | @item x-pointer-shape | |
1387 | @vindex x-pointer-shape | |
1388 | This variable specifies the pointer shape to use ordinarily in the Emacs | |
1389 | frame. | |
1390 | ||
1391 | @item x-sensitive-text-pointer-shape | |
1392 | @vindex x-sensitive-text-pointer-shape | |
1393 | This variable specifies the pointer shape to use when the mouse | |
1394 | is over mouse-sensitive text. | |
1395 | @end table | |
1396 | ||
1397 | These variables affect newly created frames. They do not normally | |
1398 | affect existing frames; however, if you set the mouse color of a frame, | |
1399 | that also updates its pointer shapes based on the current values of | |
969fe9b5 | 1400 | these variables. @xref{Window Frame Parameters}. |
bd998259 RS |
1401 | |
1402 | The values you can use, to specify either of these pointer shapes, are | |
477763cd | 1403 | defined in the file @file{lisp/term/x-win.el}. Use @kbd{M-x apropos |
bd998259 RS |
1404 | @key{RET} x-pointer @key{RET}} to see a list of them. |
1405 | ||
969fe9b5 RS |
1406 | @node Window System Selections |
1407 | @section Window System Selections | |
e294b7f1 | 1408 | @cindex selection (for window systems) |
d25390d0 RS |
1409 | |
1410 | The X server records a set of @dfn{selections} which permit transfer of | |
1411 | data between application programs. The various selections are | |
1412 | distinguished by @dfn{selection types}, represented in Emacs by | |
1413 | symbols. X clients including Emacs can read or set the selection for | |
1414 | any given type. | |
1415 | ||
1416 | @defun x-set-selection type data | |
1417 | This function sets a ``selection'' in the X server. It takes two | |
1418 | arguments: a selection type @var{type}, and the value to assign to it, | |
1419 | @var{data}. If @var{data} is @code{nil}, it means to clear out the | |
1420 | selection. Otherwise, @var{data} may be a string, a symbol, an integer | |
1421 | (or a cons of two integers or list of two integers), an overlay, or a | |
1422 | cons of two markers pointing to the same buffer. An overlay or a pair | |
1423 | of markers stands for text in the overlay or between the markers. | |
1424 | ||
f9f59935 RS |
1425 | The argument @var{data} may also be a vector of valid non-vector |
1426 | selection values. | |
d25390d0 RS |
1427 | |
1428 | Each possible @var{type} has its own selection value, which changes | |
1429 | independently. The usual values of @var{type} are @code{PRIMARY} and | |
1430 | @code{SECONDARY}; these are symbols with upper-case names, in accord | |
1431 | with X Window System conventions. The default is @code{PRIMARY}. | |
1432 | @end defun | |
1433 | ||
61cfa852 | 1434 | @defun x-get-selection &optional type data-type |
d25390d0 RS |
1435 | This function accesses selections set up by Emacs or by other X |
1436 | clients. It takes two optional arguments, @var{type} and | |
1437 | @var{data-type}. The default for @var{type}, the selection type, is | |
1438 | @code{PRIMARY}. | |
1439 | ||
1440 | The @var{data-type} argument specifies the form of data conversion to | |
1441 | use, to convert the raw data obtained from another X client into Lisp | |
1442 | data. Meaningful values include @code{TEXT}, @code{STRING}, | |
1443 | @code{TARGETS}, @code{LENGTH}, @code{DELETE}, @code{FILE_NAME}, | |
1444 | @code{CHARACTER_POSITION}, @code{LINE_NUMBER}, @code{COLUMN_NUMBER}, | |
1445 | @code{OWNER_OS}, @code{HOST_NAME}, @code{USER}, @code{CLASS}, | |
1446 | @code{NAME}, @code{ATOM}, and @code{INTEGER}. (These are symbols with | |
1447 | upper-case names in accord with X conventions.) The default for | |
1448 | @var{data-type} is @code{STRING}. | |
1449 | @end defun | |
1450 | ||
1451 | @cindex cut buffer | |
1452 | The X server also has a set of numbered @dfn{cut buffers} which can | |
1453 | store text or other data being moved between applications. Cut buffers | |
1454 | are considered obsolete, but Emacs supports them for the sake of X | |
1455 | clients that still use them. | |
1456 | ||
1457 | @defun x-get-cut-buffer n | |
1458 | This function returns the contents of cut buffer number @var{n}. | |
1459 | @end defun | |
1460 | ||
94886883 | 1461 | @defun x-set-cut-buffer string &optional push |
d25390d0 | 1462 | This function stores @var{string} into the first cut buffer (cut buffer |
94886883 GM |
1463 | 0). If @var{push} is @code{nil}, only the first cut buffer is changed. |
1464 | If @var{push} is non-@code{nil}, that says to move the values down | |
1465 | through the series of cut buffers, much like the way successive kills in | |
1466 | Emacs move down the kill ring. In other words, the previous value of | |
1467 | the first cut buffer moves into the second cut buffer, and the second to | |
1468 | the third, and so on through all eight cut buffers. | |
d25390d0 RS |
1469 | @end defun |
1470 | ||
ad37b071 | 1471 | @defvar selection-coding-system |
ad37b071 | 1472 | This variable specifies the coding system to use when reading and |
8241495d | 1473 | writing selections, the clipboard, or a cut buffer. @xref{Coding |
23b7c675 EZ |
1474 | Systems}. The default is @code{compound-text-with-extensions}, which |
1475 | converts to the text representation that X11 normally uses. | |
ad37b071 RS |
1476 | @end defvar |
1477 | ||
8241495d RS |
1478 | @cindex clipboard support (for MS-Windows) |
1479 | When Emacs runs on MS-Windows, it does not implement X selections in | |
1ecbf4e4 | 1480 | general, but it does support the clipboard. @code{x-get-selection} |
8241495d RS |
1481 | and @code{x-set-selection} on MS-Windows support the text data type |
1482 | only; if the clipboard holds other types of data, Emacs treats the | |
1483 | clipboard as empty. | |
1484 | ||
1485 | @defopt x-select-enable-clipboard | |
1486 | If this is non-@code{nil}, the Emacs yank functions consult the | |
1487 | clipboard before the primary selection, and the kill functions store in | |
1488 | the clipboard as well as the primary selection. Otherwise they do not | |
1489 | access the clipboard at all. The default is @code{nil} on most systems, | |
1490 | but @code{t} on MS-Windows. | |
1491 | @end defopt | |
a9f0a989 | 1492 | |
bfe721d1 KH |
1493 | @node Color Names |
1494 | @section Color Names | |
d25390d0 | 1495 | |
8241495d | 1496 | These functions provide a way to determine which color names are |
5df7058c EZ |
1497 | valid, and what they look like. In some cases, the value depends on the |
1498 | @dfn{selected frame}, as described below; see @ref{Input Focus}, for the | |
1499 | meaning of the term ``selected frame''. | |
8241495d RS |
1500 | |
1501 | @defun color-defined-p color &optional frame | |
1502 | @tindex color-defined-p | |
fed7c77a | 1503 | This function reports whether a color name is meaningful. It returns |
a3431be8 RS |
1504 | @code{t} if so; otherwise, @code{nil}. The argument @var{frame} says |
1505 | which frame's display to ask about; if @var{frame} is omitted or | |
1506 | @code{nil}, the selected frame is used. | |
d25390d0 | 1507 | |
fed7c77a | 1508 | Note that this does not tell you whether the display you are using |
8241495d RS |
1509 | really supports that color. When using X, you can ask for any defined |
1510 | color on any kind of display, and you will get some result---typically, | |
72821190 RS |
1511 | the closest it can do. To determine whether a frame can really display |
1512 | a certain color, use @code{color-supported-p} (see below). | |
8241495d | 1513 | |
72821190 | 1514 | @findex x-color-defined-p |
8241495d RS |
1515 | This function used to be called @code{x-color-defined-p}, |
1516 | and that name is still supported as an alias. | |
1517 | @end defun | |
1518 | ||
1519 | @defun defined-colors &optional frame | |
1520 | @tindex defined-colors | |
1521 | This function returns a list of the color names that are defined | |
1522 | and supported on frame @var{frame} (default, the selected frame). | |
1523 | ||
72821190 | 1524 | @findex x-defined-colors |
8241495d RS |
1525 | This function used to be called @code{x-defined-colors}, |
1526 | and that name is still supported as an alias. | |
fed7c77a RS |
1527 | @end defun |
1528 | ||
72821190 RS |
1529 | @defun color-supported-p color &optional frame background-p |
1530 | @tindex color-supported-p | |
1531 | This returns @code{t} if @var{frame} can really display the color | |
1532 | @var{color} (or at least something close to it). If @var{frame} is | |
1533 | omitted or @code{nil}, the question applies to the selected frame. | |
1534 | ||
1535 | Some terminals support a different set of colors for foreground and | |
1536 | background. If @var{background-p} is non-@code{nil}, that means you are | |
1537 | asking whether @var{color} can be used as a background; otherwise you | |
1538 | are asking whether it can be used as a foreground. | |
1539 | ||
1540 | The argument @var{color} must be a valid color name. | |
1541 | @end defun | |
1542 | ||
1543 | @defun color-gray-p color &optional frame | |
1544 | @tindex color-gray-p | |
1545 | This returns @code{t} if @var{color} is a shade of gray, as defined on | |
1546 | @var{frame}'s display. If @var{frame} is omitted or @code{nil}, the | |
1547 | question applies to the selected frame. The argument @var{color} must | |
1548 | be a valid color name. | |
1549 | @end defun | |
1550 | ||
8241495d RS |
1551 | @defun color-values color &optional frame |
1552 | @tindex color-values | |
fed7c77a RS |
1553 | This function returns a value that describes what @var{color} should |
1554 | ideally look like. If @var{color} is defined, the value is a list of | |
1555 | three integers, which give the amount of red, the amount of green, and | |
1556 | the amount of blue. Each integer ranges in principle from 0 to 65535, | |
8241495d RS |
1557 | but in practice no value seems to be above 65280. This kind |
1558 | of three-element list is called an @dfn{rgb value}. | |
1559 | ||
1560 | If @var{color} is not defined, the value is @code{nil}. | |
fed7c77a RS |
1561 | |
1562 | @example | |
8241495d | 1563 | (color-values "black") |
fed7c77a | 1564 | @result{} (0 0 0) |
8241495d | 1565 | (color-values "white") |
fed7c77a | 1566 | @result{} (65280 65280 65280) |
8241495d | 1567 | (color-values "red") |
fed7c77a | 1568 | @result{} (65280 0 0) |
8241495d | 1569 | (color-values "pink") |
fed7c77a | 1570 | @result{} (65280 49152 51968) |
8241495d | 1571 | (color-values "hungry") |
fed7c77a RS |
1572 | @result{} nil |
1573 | @end example | |
a3431be8 RS |
1574 | |
1575 | The color values are returned for @var{frame}'s display. If @var{frame} | |
1911e6e5 | 1576 | is omitted or @code{nil}, the information is returned for the selected |
a3431be8 | 1577 | frame's display. |
8241495d | 1578 | |
72821190 | 1579 | @findex x-color-values |
8241495d RS |
1580 | This function used to be called @code{x-color-values}, |
1581 | and that name is still supported as an alias. | |
1582 | @end defun | |
1583 | ||
1584 | @node Text Terminal Colors | |
1585 | @section Text Terminal Colors | |
1586 | @cindex colors on text-only terminals | |
1587 | ||
1588 | Emacs can display color on text-only terminals, starting with version | |
8d78fe22 EZ |
1589 | 21. These terminals usually support only a small number of colors, and |
1590 | the computer uses small integers to select colors on the terminal. This | |
8241495d RS |
1591 | means that the computer cannot reliably tell what the selected color |
1592 | looks like; instead, you have to inform your application which small | |
1593 | integers correspond to which colors. However, Emacs does know the | |
1594 | standard set of colors and will try to use them automatically. | |
1595 | ||
8d78fe22 EZ |
1596 | The functions described in this section control how terminal colors |
1597 | are used by Emacs. | |
1598 | ||
8241495d RS |
1599 | @cindex rgb value |
1600 | Several of these functions use or return @dfn{rgb values}. An rgb | |
1601 | value is a list of three integers, which give the amount of red, the | |
1602 | amount of green, and the amount of blue. Each integer ranges in | |
1603 | principle from 0 to 65535, but in practice the largest value used is | |
1604 | 65280. | |
1605 | ||
75708135 RS |
1606 | These functions accept a display (either a frame or the name of a |
1607 | terminal) as an optional argument. We hope in the future to make Emacs | |
1608 | support more than one text-only terminal at one time; then this argument | |
1609 | will specify which terminal to operate on (the default being the | |
5df7058c EZ |
1610 | selected frame's terminal; @pxref{Input Focus}). At present, though, |
1611 | the @var{display} argument has no effect. | |
72821190 | 1612 | |
75708135 | 1613 | @defun tty-color-define name number &optional rgb display |
72821190 | 1614 | @tindex tty-color-define |
8241495d RS |
1615 | This function associates the color name @var{name} with |
1616 | color number @var{number} on the terminal. | |
1617 | ||
1618 | The optional argument @var{rgb}, if specified, is an rgb value; it says | |
1619 | what the color actually looks like. If you do not specify @var{rgb}, | |
1620 | then this color cannot be used by @code{tty-color-approximate} to | |
1621 | approximate other colors, because Emacs does not know what it looks | |
1622 | like. | |
1623 | @end defun | |
1624 | ||
75708135 | 1625 | @defun tty-color-clear &optional display |
72821190 | 1626 | @tindex tty-color-clear |
8241495d RS |
1627 | This function clears the table of defined colors for a text-only terminal. |
1628 | @end defun | |
1629 | ||
75708135 | 1630 | @defun tty-color-alist &optional display |
8241495d | 1631 | @tindex tty-color-alist |
72821190 RS |
1632 | This function returns an alist recording the known colors supported by a |
1633 | text-only terminal. | |
8241495d RS |
1634 | |
1635 | Each element has the form @code{(@var{name} @var{number} . @var{rgb})} | |
1636 | or @code{(@var{name} @var{number})}. Here, @var{name} is the color | |
1637 | name, @var{number} is the number used to specify it to the terminal. | |
1638 | If present, @var{rgb} is an rgb value that says what the color | |
1639 | actually looks like. | |
72821190 | 1640 | @end defun |
8241495d | 1641 | |
75708135 | 1642 | @defun tty-color-approximate rgb &optional display |
8241495d | 1643 | @tindex tty-color-approximate |
72821190 | 1644 | This function finds the closest color, among the known colors supported |
75708135 | 1645 | for @var{display}, to that described by the rgb value @var{rgb}. |
8241495d RS |
1646 | @end defun |
1647 | ||
75708135 | 1648 | @defun tty-color-translate color &optional display |
8241495d | 1649 | @tindex tty-color-translate |
72821190 | 1650 | This function finds the closest color to @var{color} among the known |
75708135 RS |
1651 | colors supported for @var{display}. If the name @var{color} is not |
1652 | defined, the value is @code{nil}. | |
8241495d | 1653 | |
72821190 RS |
1654 | @var{color} can be an X-style @code{"#@var{xxxyyyzzz}"} specification |
1655 | instead of an actual name. The format | |
1656 | @code{"RGB:@var{xx}/@var{yy}/@var{zz}"} is also supported. | |
d25390d0 RS |
1657 | @end defun |
1658 | ||
d25390d0 RS |
1659 | @node Resources |
1660 | @section X Resources | |
1661 | ||
bfe721d1 | 1662 | @defun x-get-resource attribute class &optional component subclass |
d25390d0 RS |
1663 | The function @code{x-get-resource} retrieves a resource value from the X |
1664 | Windows defaults database. | |
1665 | ||
1666 | Resources are indexed by a combination of a @dfn{key} and a @dfn{class}. | |
1667 | This function searches using a key of the form | |
61cfa852 | 1668 | @samp{@var{instance}.@var{attribute}} (where @var{instance} is the name |
bfe721d1 KH |
1669 | under which Emacs was invoked), and using @samp{Emacs.@var{class}} as |
1670 | the class. | |
d25390d0 RS |
1671 | |
1672 | The optional arguments @var{component} and @var{subclass} add to the key | |
1673 | and the class, respectively. You must specify both of them or neither. | |
1674 | If you specify them, the key is | |
1675 | @samp{@var{instance}.@var{component}.@var{attribute}}, and the class is | |
bfe721d1 | 1676 | @samp{Emacs.@var{class}.@var{subclass}}. |
d25390d0 RS |
1677 | @end defun |
1678 | ||
f9f59935 RS |
1679 | @defvar x-resource-class |
1680 | This variable specifies the application name that @code{x-get-resource} | |
1681 | should look up. The default value is @code{"Emacs"}. You can examine X | |
1682 | resources for application names other than ``Emacs'' by binding this | |
1683 | variable to some other string, around a call to @code{x-get-resource}. | |
1684 | @end defvar | |
1685 | ||
61f7e0f5 | 1686 | @xref{X Resources,, X Resources, emacs, The GNU Emacs Manual}. |
d25390d0 | 1687 | |
a065c889 RS |
1688 | @node Display Feature Testing |
1689 | @section Display Feature Testing | |
1690 | @cindex display feature testing | |
1691 | ||
1692 | The functions in this section describe the basic capabilities of a | |
1693 | particular display. Lisp programs can use them to adapt their behavior | |
5fe3b9bc | 1694 | to what the display can do. For example, a program that ordinarily uses |
a065c889 RS |
1695 | a popup menu could use the minibuffer if popup menus are not supported. |
1696 | ||
1697 | The optional argument @var{display} in these functions specifies which | |
1698 | display to ask the question about. It can be a display name, a frame | |
1699 | (which designates the display that frame is on), or @code{nil} (which | |
5df7058c | 1700 | refers to the selected frame's display, @pxref{Input Focus}). |
a065c889 RS |
1701 | |
1702 | @xref{Color Names}, @ref{Text Terminal Colors}, for other functions to | |
1703 | obtain information about displays. | |
1704 | ||
1705 | @defun display-popup-menus-p &optional display | |
1706 | @tindex display-popup-menus-p | |
1707 | This function returns @code{t} if popup menus are supported on | |
1708 | @var{display}, @code{nil} if not. Support for popup menus requires that | |
1709 | the mouse be available, since the user cannot choose menu items without | |
1710 | a mouse. | |
1711 | @end defun | |
1712 | ||
1713 | @defun display-graphic-p &optional display | |
1714 | @tindex display-graphic-p | |
1715 | @cindex frames, more than one on display | |
1716 | @cindex fonts, more than one on display | |
1717 | This function returns @code{t} if @var{display} is a graphic display | |
1718 | capable of displaying several frames and several different fonts at | |
1719 | once. This is true for displays that use a window system such as X, and | |
1720 | false for text-only terminals. | |
1721 | @end defun | |
1722 | ||
1dffc5db RS |
1723 | @defun display-mouse-p &optional display |
1724 | @tindex display-mouse-p | |
1725 | @cindex mouse, availability | |
1726 | This function returns @code{t} if @var{display} has a mouse available, | |
1727 | @code{nil} if not. | |
1728 | @end defun | |
1729 | ||
12210d03 RS |
1730 | @defun display-color-p &optional display |
1731 | @tindex display-color-p | |
1732 | @findex x-display-color-p | |
1733 | This function returns @code{t} if the screen is a color screen. | |
1734 | It used to be called @code{x-display-color-p}, and that name | |
1735 | is still supported as an alias. | |
1736 | @end defun | |
1737 | ||
1738 | @defun display-grayscale-p &optional display | |
1739 | @tindex display-grayscale-p | |
1740 | This function returns @code{t} if the screen can display shades of gray. | |
1dffc5db | 1741 | (All color displays can do this.) |
12210d03 RS |
1742 | @end defun |
1743 | ||
11ef2a3b MB |
1744 | @anchor{Display Face Attribute Testing} |
1745 | @defun display-supports-face-attributes-p attributes &optional display | |
1746 | @tindex display-supports-face-attributes-p | |
1747 | This function returns non-@code{nil} if all the face attributes in | |
1748 | @var{attributes} are supported (@pxref{Face Attributes}). | |
1749 | ||
1750 | The definition of `supported' is somewhat heuristic, but basically | |
1751 | means that a face containing all the attributes in @var{attributes}, | |
1752 | when merged with the default face for display, can be represented in a | |
1753 | way that's | |
1754 | ||
1755 | @enumerate | |
1756 | @item | |
1757 | different in appearance than the default face, and | |
1758 | ||
1759 | @item | |
1760 | `close in spirit' to what the attributes specify, if not exact. | |
1761 | @end enumerate | |
1762 | ||
1763 | Point (2) implies that a @code{:weight black} attribute will be | |
1764 | satisfied by any display that can display bold, as will | |
1765 | @code{:foreground "yellow"} as long as some yellowish color can be | |
72459b15 | 1766 | displayed, but @code{:slant italic} will @emph{not} be satisfied by |
11ef2a3b MB |
1767 | the tty display code's automatic substitution of a `dim' face for |
1768 | italic. | |
1769 | @end defun | |
1770 | ||
a065c889 RS |
1771 | @defun display-selections-p &optional display |
1772 | @tindex display-selections-p | |
1773 | This function returns @code{t} if @var{display} supports selections. | |
1774 | Windowed displays normally support selections, but they may also be | |
1775 | supported in some other cases. | |
1776 | @end defun | |
d25390d0 | 1777 | |
28932ac1 EZ |
1778 | @defun display-images-p &optional display |
1779 | This function returns @code{t} if @var{display} can display images. | |
caae20c7 RS |
1780 | Windowed displays ought in principle to handle images, but some |
1781 | systems lack the support for that. On a display that does not support | |
1782 | images, Emacs cannot display a tool bar. | |
28932ac1 EZ |
1783 | @end defun |
1784 | ||
12210d03 RS |
1785 | @defun display-screens &optional display |
1786 | @tindex display-screens | |
22697dac | 1787 | This function returns the number of screens associated with the display. |
d25390d0 RS |
1788 | @end defun |
1789 | ||
12210d03 RS |
1790 | @defun display-pixel-height &optional display |
1791 | @tindex display-pixel-height | |
22697dac | 1792 | This function returns the height of the screen in pixels. |
d25390d0 RS |
1793 | @end defun |
1794 | ||
12210d03 RS |
1795 | @defun display-mm-height &optional display |
1796 | @tindex display-mm-height | |
1797 | This function returns the height of the screen in millimeters, | |
1798 | or @code{nil} if Emacs cannot get that information. | |
d25390d0 RS |
1799 | @end defun |
1800 | ||
12210d03 RS |
1801 | @defun display-pixel-width &optional display |
1802 | @tindex display-pixel-width | |
22697dac | 1803 | This function returns the width of the screen in pixels. |
d25390d0 RS |
1804 | @end defun |
1805 | ||
12210d03 RS |
1806 | @defun display-mm-width &optional display |
1807 | @tindex display-mm-width | |
1808 | This function returns the width of the screen in millimeters, | |
1809 | or @code{nil} if Emacs cannot get that information. | |
d25390d0 RS |
1810 | @end defun |
1811 | ||
12210d03 RS |
1812 | @defun display-backing-store &optional display |
1813 | @tindex display-backing-store | |
1dffc5db RS |
1814 | This function returns the backing store capability of the display. |
1815 | Backing store means recording the pixels of windows (and parts of | |
1816 | windows) that are not exposed, so that when exposed they can be | |
1817 | displayed very quickly. | |
1818 | ||
d25390d0 | 1819 | Values can be the symbols @code{always}, @code{when-mapped}, or |
12210d03 RS |
1820 | @code{not-useful}. The function can also return @code{nil} |
1821 | when the question is inapplicable to a certain kind of display. | |
d25390d0 RS |
1822 | @end defun |
1823 | ||
12210d03 RS |
1824 | @defun display-save-under &optional display |
1825 | @tindex display-save-under | |
22697dac | 1826 | This function returns non-@code{nil} if the display supports the |
1dffc5db RS |
1827 | SaveUnder feature. That feature is used by pop-up windows |
1828 | to save the pixels they obscure, so that they can pop down | |
1829 | quickly. | |
d25390d0 RS |
1830 | @end defun |
1831 | ||
12210d03 RS |
1832 | @defun display-planes &optional display |
1833 | @tindex display-planes | |
22697dac | 1834 | This function returns the number of planes the display supports. |
1dffc5db | 1835 | This is typically the number of bits per pixel. |
7aa2024d | 1836 | For a tty display, it is log to base two of the number of colours supported. |
d25390d0 RS |
1837 | @end defun |
1838 | ||
12210d03 RS |
1839 | @defun display-visual-class &optional display |
1840 | @tindex display-visual-class | |
22697dac KH |
1841 | This function returns the visual class for the screen. The value is one |
1842 | of the symbols @code{static-gray}, @code{gray-scale}, | |
d25390d0 RS |
1843 | @code{static-color}, @code{pseudo-color}, @code{true-color}, and |
1844 | @code{direct-color}. | |
1845 | @end defun | |
1846 | ||
12210d03 RS |
1847 | @defun display-color-cells &optional display |
1848 | @tindex display-color-cells | |
1849 | This function returns the number of color cells the screen supports. | |
22697dac KH |
1850 | @end defun |
1851 | ||
12210d03 RS |
1852 | These functions obtain additional information specifically |
1853 | about X displays. | |
1854 | ||
1855 | @defun x-server-version &optional display | |
1856 | This function returns the list of version numbers of the X server | |
1857 | running the display. | |
1858 | @end defun | |
1859 | ||
1860 | @defun x-server-vendor &optional display | |
1861 | This function returns the vendor that provided the X server software. | |
d25390d0 RS |
1862 | @end defun |
1863 | ||
1864 | @ignore | |
1865 | @defvar x-no-window-manager | |
a9f0a989 | 1866 | This variable's value is @code{t} if no X window manager is in use. |
d25390d0 RS |
1867 | @end defvar |
1868 | @end ignore | |
1869 | ||
1870 | @ignore | |
1871 | @item | |
1872 | The functions @code{x-pixel-width} and @code{x-pixel-height} return the | |
1873 | width and height of an X Window frame, measured in pixels. | |
d25390d0 | 1874 | @end ignore |