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1 | @c -*-texinfo-*- |
2 | @c This is part of the GNU Emacs Lisp Reference Manual. | |
3 | @c Copyright (C) 1990, 1991, 1992, 1993, 1994 Free Software Foundation, Inc. | |
4 | @c See the file elisp.texi for copying conditions. | |
5 | @setfilename ../info/frames | |
6 | @node Frames, Positions, Windows, Top | |
7 | @chapter Frames | |
8 | @cindex frame | |
9 | ||
1a426e9b | 10 | A @dfn{frame} is a rectangle on the screen that contains one or more |
d25390d0 | 11 | Emacs windows. A frame initially contains a single main window (plus |
61cfa852 | 12 | perhaps a minibuffer window), which you can subdivide vertically or |
d25390d0 RS |
13 | horizontally into smaller windows. |
14 | ||
15 | @cindex terminal frame | |
16 | @cindex X window 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 | ||
bfe721d1 KH |
21 | When Emacs communicates directly with an X server, it does not have a |
22 | terminal frame; instead, it starts with a single @dfn{X window frame}. | |
23 | It can display multiple X window frames at the same time, each in its | |
24 | own X window. | |
d25390d0 RS |
25 | |
26 | @defun framep object | |
27 | This predicate returns @code{t} if @var{object} is a frame, and | |
28 | @code{nil} otherwise. | |
29 | @end defun | |
30 | ||
31 | @menu | |
22697dac KH |
32 | * Creating Frames:: Creating additional frames. |
33 | * Multiple Displays:: Creating frames on other X displays. | |
d25390d0 | 34 | * Frame Parameters:: Controlling frame size, position, font, etc. |
22697dac | 35 | * Frame Titles:: Automatic updating of frame titles. |
d25390d0 RS |
36 | * Deleting Frames:: Frames last until explicitly deleted. |
37 | * Finding All Frames:: How to examine all existing frames. | |
38 | * Frames and Windows:: A frame contains windows; | |
39 | display of text always works through windows. | |
40 | * Minibuffers and Frames:: How a frame finds the minibuffer to use. | |
41 | * Input Focus:: Specifying the selected frame. | |
42 | * Visibility of Frames:: Frames may be visible or invisible, or icons. | |
43 | * Raising and Lowering:: Raising a frame makes it hide other X windows; | |
44 | lowering it makes the others hide them. | |
45 | * Frame Configurations:: Saving the state of all frames. | |
46 | * Mouse Tracking:: Getting events that say when the mouse moves. | |
47 | * Mouse Position:: Asking where the mouse is, or moving it. | |
48 | * Pop-Up Menus:: Displaying a menu for the user to select from. | |
49 | * Dialog Boxes:: Displaying a box to ask yes or no. | |
bd998259 | 50 | * Pointer Shapes:: Specifying the shape of the mouse pointer. |
d25390d0 | 51 | * X Selections:: Transferring text to and from other X clients. |
bfe721d1 | 52 | * Color Names:: Getting the definitions of color names. |
d25390d0 RS |
53 | * Resources:: Getting resource values from the server. |
54 | * Server Data:: Getting info about the X server. | |
55 | @end menu | |
56 | ||
57 | @xref{Display}, for related information. | |
58 | ||
59 | @node Creating Frames | |
60 | @section Creating Frames | |
61 | ||
62 | To create a new frame, call the function @code{make-frame}. | |
63 | ||
1a426e9b | 64 | @defun make-frame &optional alist |
22697dac KH |
65 | This function creates a new frame. If you are using X, it makes |
66 | an X window frame; otherwise, it makes a terminal frame. | |
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67 | |
68 | The argument is an alist specifying frame parameters. Any parameters | |
69 | not mentioned in @var{alist} default according to the value of the | |
bfe721d1 KH |
70 | variable @code{default-frame-alist}; parameters not specified even there |
71 | default from the standard X defaults file and X resources. | |
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72 | |
73 | The set of possible parameters depends in principle on what kind of | |
61cfa852 | 74 | window system Emacs uses to display its frames. @xref{X Frame |
22697dac | 75 | Parameters}, for documentation of individual parameters you can specify. |
d25390d0 RS |
76 | @end defun |
77 | ||
d25390d0 RS |
78 | @defvar before-make-frame-hook |
79 | A normal hook run by @code{make-frame} before it actually creates the | |
80 | frame. | |
81 | @end defvar | |
82 | ||
83 | @defvar after-make-frame-hook | |
84 | A normal hook run by @code{make-frame} after it creates the frame. | |
85 | @end defvar | |
86 | ||
22697dac KH |
87 | @node Multiple Displays |
88 | @section Multiple Displays | |
89 | @cindex multiple displays | |
90 | @cindex multiple X terminals | |
91 | @cindex displays, multiple | |
92 | ||
93 | A single Emacs can talk to more than one X Windows display. | |
94 | Initially, Emacs uses just one display---the one chosen with the | |
95 | @code{DISPLAY} environment variable or with the @samp{--display} option | |
96 | (@pxref{Initial Options,,, emacs, The GNU Emacs Manual}). To connect to | |
97 | another display, use the command @code{make-frame-on-display} or specify | |
98 | the @code{display} frame parameter when you create the frame. | |
99 | ||
100 | Emacs treats each X server as a separate terminal, giving each one its | |
101 | own selected frame and its own minibuffer windows. A few Lisp variables | |
102 | have values local to the current terminal (that is, the terminal | |
103 | corresponding to the currently selected frame): these are | |
104 | @code{default-minibuffer-frame}, @code{defining-kbd-macro}, | |
a3431be8 RS |
105 | @code{last-kbd-macro}, and @code{system-key-alist}. These variables are |
106 | always terminal-local and can never be buffer-local. | |
22697dac KH |
107 | |
108 | A single X server can handle more than one screen. A display name | |
109 | @samp{@var{host}.@var{server}.@var{screen}} has three parts; the last | |
110 | part specifies the screen number for a given server. When you use two | |
111 | screens belonging to one server, Emacs knows by the similarity in their | |
112 | names that they share a single keyboard, and it treats them as a single | |
113 | terminal. | |
114 | ||
115 | @deffn Command make-frame-on-display display &optional parameters | |
116 | This creates a new frame on display @var{display}, taking the other | |
117 | frame parameters from @var{parameters}. Aside from the @var{display} | |
118 | argument, it is like @code{make-frame} (@pxref{Creating Frames}). | |
119 | @end deffn | |
120 | ||
121 | @defun x-display-list | |
122 | This returns a list that indicates which X displays Emacs has a | |
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123 | connection to. The elements of the list are strings, and each one is |
124 | a display name. | |
22697dac KH |
125 | @end defun |
126 | ||
127 | @defun x-open-connection display &optional xrm-string | |
128 | This function opens a connection to the X display @var{display}. It | |
129 | does not create a frame on that display, but it permits you to check | |
130 | that communication can be established with that display. | |
131 | ||
bfe721d1 KH |
132 | The optional argument @var{resource-string}, if not @code{nil}, is a |
133 | string of resource names and values, in the same format used in the | |
134 | @file{.Xresources} file. The values you specify override the resource | |
135 | values recorded in the X server itself; they apply to all Emacs frames | |
136 | created on this display. Here's an example of what this string might | |
137 | look like: | |
138 | ||
139 | @example | |
140 | "*BorderWidth: 3\n*InternalBorder: 2\n" | |
141 | @end example | |
142 | ||
143 | @xref{Resources}. | |
22697dac KH |
144 | @end defun |
145 | ||
146 | @defun x-close-connection display | |
147 | This function closes the connection to display @var{display}. Before | |
148 | you can do this, you must first delete all the frames that were open on | |
149 | that display (@pxref{Deleting Frames}). | |
150 | @end defun | |
151 | ||
d25390d0 RS |
152 | @node Frame Parameters |
153 | @section Frame Parameters | |
154 | ||
155 | A frame has many parameters that control its appearance and behavior. | |
156 | Just what parameters a frame has depends on what display mechanism it | |
157 | uses. | |
158 | ||
159 | Frame parameters exist for the sake of window systems. A terminal frame | |
bfe721d1 KH |
160 | has a few parameters, mostly for compatibility's sake; only the height, |
161 | width and @code{buffer-predicate} parameters really do something. | |
d25390d0 RS |
162 | |
163 | @menu | |
164 | * Parameter Access:: How to change a frame's parameters. | |
165 | * Initial Parameters:: Specifying frame parameters when you make a frame. | |
22697dac | 166 | * X Frame Parameters:: List of frame parameters. |
fb9b5ab7 | 167 | * Size and Position:: Changing the size and position of a frame. |
d25390d0 RS |
168 | @end menu |
169 | ||
170 | @node Parameter Access | |
171 | @subsection Access to Frame Parameters | |
172 | ||
173 | These functions let you read and change the parameter values of a | |
174 | frame. | |
175 | ||
176 | @defun frame-parameters frame | |
177 | The function @code{frame-parameters} returns an alist listing all the | |
178 | parameters of @var{frame} and their values. | |
179 | @end defun | |
180 | ||
181 | @defun modify-frame-parameters frame alist | |
182 | This function alters the parameters of frame @var{frame} based on the | |
183 | elements of @var{alist}. Each element of @var{alist} has the form | |
184 | @code{(@var{parm} . @var{value})}, where @var{parm} is a symbol naming a | |
185 | parameter. If you don't mention a parameter in @var{alist}, its value | |
186 | doesn't change. | |
187 | @end defun | |
188 | ||
189 | @node Initial Parameters | |
190 | @subsection Initial Frame Parameters | |
191 | ||
192 | You can specify the parameters for the initial startup frame | |
193 | by setting @code{initial-frame-alist} in your @file{.emacs} file. | |
194 | ||
195 | @defvar initial-frame-alist | |
196 | This variable's value is an alist of parameter values used when creating | |
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197 | the initial X window frame. Each element has the form: |
198 | ||
199 | @example | |
200 | (@var{parameter} . @var{value}) | |
201 | @end example | |
202 | ||
203 | Emacs creates the initial frame before it reads your @file{~/.emacs} | |
204 | file. After reading that file, Emacs checks @code{initial-frame-alist}, | |
205 | and applies the parameter settings in the altered value to the already | |
206 | created initial frame. | |
207 | ||
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208 | If these settings affect the frame geometry and appearance, you'll see |
209 | the frame appear with the wrong ones and then change to the specified | |
210 | ones. If that bothers you, you can specify the same geometry and | |
211 | appearance with X resources; those do take affect before the frame is | |
212 | created. @xref{Resources X,, X Resources, emacs, The GNU Emacs Manual}. | |
1e2300d3 RS |
213 | |
214 | X resource settings typically apply to all frames. If you want to | |
215 | specify some X resources solely for the sake of the initial frame, and | |
216 | you don't want them to apply to subsequent frames, here's how to achieve | |
217 | this. Specify parameters in @code{default-frame-alist} to override the | |
218 | X resources for subsequent frames; then, to prevent these from affecting | |
219 | the initial frame, specify the same parameters in | |
220 | @code{initial-frame-alist} with values that match the X resources. | |
d25390d0 RS |
221 | @end defvar |
222 | ||
bfe721d1 KH |
223 | If these parameters specify a separate minibuffer-only frame with |
224 | @code{(minibuffer . nil)}, and you have not created one, Emacs creates | |
225 | one for you. | |
d25390d0 RS |
226 | |
227 | @defvar minibuffer-frame-alist | |
228 | This variable's value is an alist of parameter values used when creating | |
229 | an initial minibuffer-only frame---if such a frame is needed, according | |
230 | to the parameters for the main initial frame. | |
231 | @end defvar | |
232 | ||
1e2300d3 RS |
233 | @defvar default-frame-alist |
234 | This is an alist specifying default values of frame parameters for | |
235 | subsequent Emacs frames (not the initial ones). | |
236 | @end defvar | |
237 | ||
bfe721d1 KH |
238 | See also @code{special-display-frame-alist}, in @ref{Choosing Window}. |
239 | ||
1e2300d3 RS |
240 | If you use options that specify window appearance when you invoke Emacs, |
241 | they take effect by adding elements to @code{default-frame-alist}. One | |
bfe721d1 KH |
242 | exception is @samp{-geometry}, which adds the specified position to |
243 | @code{initial-frame-alist} instead. @xref{Command Arguments,,, emacs, | |
244 | The GNU Emacs Manual}. | |
1e2300d3 | 245 | |
d25390d0 RS |
246 | @node X Frame Parameters |
247 | @subsection X Window Frame Parameters | |
248 | ||
249 | Just what parameters a frame has depends on what display mechanism it | |
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250 | uses. Here is a table of the parameters of an X window frame; of these, |
251 | @code{name}, @code{height}, @code{width}, and @code{buffer-predicate} | |
252 | provide meaningful information in non-X frames. | |
d25390d0 RS |
253 | |
254 | @table @code | |
255 | @item name | |
256 | The name of the frame. Most window managers display the frame's name in | |
257 | the frame's border, at the top of the frame. If you don't specify a | |
258 | name, and you have more than one frame, Emacs sets the frame name based | |
259 | on the buffer displayed in the frame's selected window. | |
260 | ||
261 | If you specify the frame name explicitly when you create the frame, the | |
262 | name is also used (instead of the name of the Emacs executable) when | |
263 | looking up X resources for the frame. | |
264 | ||
22697dac KH |
265 | @item display |
266 | The display on which to open this frame. It should be a string of the | |
267 | form @code{"@var{host}:@var{dpy}.@var{screen}"}, just like the | |
268 | @code{DISPLAY} environment variable. | |
269 | ||
d25390d0 | 270 | @item left |
22697dac KH |
271 | The screen position of the left edge, in pixels, with respect to the |
272 | left edge of the screen. The value may be a positive number @var{pos}, | |
273 | or a list of the form @code{(+ @var{pos})} which permits specifying a | |
274 | negative @var{pos} value. | |
275 | ||
276 | A negative number @minus{}@var{pos}, or a list of the form @code{(- | |
277 | @var{pos})}, actually specifies the position of the right edge of the | |
bfe721d1 KH |
278 | window with respect to the right edge of the screen. A positive value |
279 | of @var{pos} counts toward the left. If the parameter is a negative | |
280 | integer @minus{}@var{pos} then @var{pos} is positive! | |
d25390d0 | 281 | |
53c47801 RS |
282 | Some window managers ignore program-specified positions. If you want to |
283 | be sure the position you specify is not ignored, specify a | |
284 | non-@code{nil} value for the @code{user-position} parameter as well. | |
285 | ||
d25390d0 | 286 | @item top |
22697dac KH |
287 | The screen position of the top edge, in pixels, with respect to the |
288 | top edge of the screen. The value may be a positive number @var{pos}, | |
289 | or a list of the form @code{(+ @var{pos})} which permits specifying a | |
290 | negative @var{pos} value. | |
291 | ||
292 | A negative number @minus{}@var{pos}, or a list of the form @code{(- | |
293 | @var{pos})}, actually specifies the position of the bottom edge of the | |
bfe721d1 KH |
294 | window with respect to the bottom edge of the screen. A positive value |
295 | of @var{pos} counts toward the top. If the parameter is a negative | |
296 | integer @minus{}@var{pos} then @var{pos} is positive! | |
bd998259 | 297 | |
53c47801 RS |
298 | Some window managers ignore program-specified positions. If you want to |
299 | be sure the position you specify is not ignored, specify a | |
300 | non-@code{nil} value for the @code{user-position} parameter as well. | |
301 | ||
906848bd RS |
302 | @item icon-left |
303 | The screen position of the left edge @emph{of the frame's icon}, in | |
304 | pixels, counting from the left edge of the screen. This takes effect if | |
305 | and when the frame is iconified. | |
306 | ||
307 | @item icon-top | |
308 | The screen position of the top edge @emph{of the frame's icon}, in | |
309 | pixels, counting from the top edge of the screen. This takes effect if | |
310 | and when the frame is iconified. | |
311 | ||
bd998259 | 312 | @item user-position |
cee8c3b3 RS |
313 | When you create a frame and specify its screen position with the |
314 | @code{left} and @code{top} parameters, use this parameter to say whether | |
315 | the specified position was user-specified (explicitly requested in some | |
316 | way by a human user) or merely program-specified (chosen by a program). | |
317 | A non-@code{nil} value says the position was user-specified. | |
318 | ||
319 | Window managers generally heed user-specified positions, and some heed | |
320 | program-specified positions too. But many ignore program-specified | |
321 | positions, placing the window in a default fashion or letting the user | |
322 | place it with the mouse. Some window managers, including @code{twm}, | |
323 | let the user specify whether to obey program-specified positions or | |
324 | ignore them. | |
325 | ||
326 | When you call @code{make-frame}, you should specify a non-@code{nil} | |
327 | value for this parameter if the values of the @code{left} and @code{top} | |
328 | parameters represent the user's stated preference; otherwise, use | |
329 | @code{nil}. | |
d25390d0 RS |
330 | |
331 | @item height | |
fb9b5ab7 RS |
332 | The height of the frame contents, in characters. (To get the height in |
333 | pixels, call @code{frame-pixel-height}; see @ref{Size and Position}.) | |
d25390d0 RS |
334 | |
335 | @item width | |
fb9b5ab7 RS |
336 | The width of the frame contents, in characters. (To get the height in |
337 | pixels, call @code{frame-pixel-width}; see @ref{Size and Position}.) | |
d25390d0 RS |
338 | |
339 | @item window-id | |
340 | The number of the X window for the frame. | |
341 | ||
342 | @item minibuffer | |
343 | Whether this frame has its own minibuffer. The value @code{t} means | |
344 | yes, @code{nil} means no, @code{only} means this frame is just a | |
bfe721d1 KH |
345 | minibuffer. If the value is a minibuffer window (in some other frame), |
346 | the new frame uses that minibuffer. | |
d25390d0 | 347 | |
22697dac KH |
348 | @item buffer-predicate |
349 | The buffer-predicate function for this frame. The function | |
350 | @code{other-buffer} uses this predicate (from the selected frame) to | |
351 | decide which buffers it should consider, if the predicate is not | |
352 | @code{nil}. It calls the predicate with one arg, a buffer, once for | |
353 | each buffer; if the predicate returns a non-@code{nil} value, it | |
354 | considers that buffer. | |
355 | ||
d25390d0 RS |
356 | @item font |
357 | The name of the font for displaying text in the frame. This is a | |
358 | string. | |
359 | ||
360 | @item auto-raise | |
361 | Whether selecting the frame raises it (non-@code{nil} means yes). | |
362 | ||
363 | @item auto-lower | |
364 | Whether deselecting the frame lowers it (non-@code{nil} means yes). | |
365 | ||
366 | @item vertical-scroll-bars | |
367 | Whether the frame has scroll bars for vertical scrolling | |
368 | (non-@code{nil} means yes). | |
369 | ||
370 | @item horizontal-scroll-bars | |
371 | Whether the frame has scroll bars for horizontal scrolling | |
372 | (non-@code{nil} means yes). (Horizontal scroll bars are not currently | |
373 | implemented.) | |
374 | ||
22697dac KH |
375 | @item scroll-bar-width |
376 | The width of the vertical scroll bar, in pixels. | |
377 | ||
d25390d0 | 378 | @item icon-type |
fd3e5741 RS |
379 | The type of icon to use for this frame when it is iconified. If the |
380 | value is a string, that specifies a file containing a bitmap to use. | |
381 | Any other non-@code{nil} value specifies the default bitmap icon (a | |
382 | picture of a gnu); @code{nil} specifies a text icon. | |
d25390d0 | 383 | |
bfe721d1 KH |
384 | @item icon-name |
385 | The name to use in the icon for this frame, when and if the icon | |
386 | appears. If this is @code{nil}, the frame's title is used. | |
387 | ||
d25390d0 | 388 | @item foreground-color |
61cfa852 | 389 | The color to use for the image of a character. This is a string; the X |
d25390d0 RS |
390 | server defines the meaningful color names. |
391 | ||
392 | @item background-color | |
61cfa852 | 393 | The color to use for the background of characters. |
d25390d0 RS |
394 | |
395 | @item mouse-color | |
bd998259 | 396 | The color for the mouse pointer. |
d25390d0 RS |
397 | |
398 | @item cursor-color | |
399 | The color for the cursor that shows point. | |
400 | ||
401 | @item border-color | |
402 | The color for the border of the frame. | |
403 | ||
404 | @item cursor-type | |
22697dac KH |
405 | The way to display the cursor. The legitimate values are @code{bar}, |
406 | @code{box}, and @code{(bar . @var{width})}. The symbol @code{box} | |
407 | specifies an ordinary black box overlaying the character after point; | |
408 | that is the default. The symbol @code{bar} specifies a vertical bar | |
409 | between characters as the cursor. @code{(bar . @var{width})} specifies | |
410 | a bar @var{width} pixels wide. | |
d25390d0 RS |
411 | |
412 | @item border-width | |
413 | The width in pixels of the window border. | |
414 | ||
415 | @item internal-border-width | |
416 | The distance in pixels between text and border. | |
417 | ||
418 | @item unsplittable | |
419 | If non-@code{nil}, this frame's window is never split automatically. | |
420 | ||
421 | @item visibility | |
422 | The state of visibility of the frame. There are three possibilities: | |
423 | @code{nil} for invisible, @code{t} for visible, and @code{icon} for | |
424 | iconified. @xref{Visibility of Frames}. | |
425 | ||
426 | @item menu-bar-lines | |
427 | The number of lines to allocate at the top of the frame for a menu bar. | |
0f6b12c9 RS |
428 | The default is 1. @xref{Menu Bar}. (In Emacs versions that use the X |
429 | toolkit, there is only one menu bar line; all that matters about the | |
430 | number you specify is whether it is greater than zero.) | |
d25390d0 RS |
431 | |
432 | @item parent-id | |
433 | @c ??? Not yet working. | |
434 | The X window number of the window that should be the parent of this one. | |
435 | Specifying this lets you create an Emacs window inside some other | |
436 | application's window. (It is not certain this will be implemented; try | |
437 | it and see if it works.) | |
438 | @end table | |
439 | ||
fb9b5ab7 | 440 | @node Size and Position |
d25390d0 RS |
441 | @subsection Frame Size And Position |
442 | ||
443 | You can read or change the size and position of a frame using the | |
61cfa852 | 444 | frame parameters @code{left}, @code{top}, @code{height}, and |
bd998259 RS |
445 | @code{width}. Whatever geometry parameters you don't specify are chosen |
446 | by the window manager in its usual fashion. | |
d25390d0 RS |
447 | |
448 | Here are some special features for working with sizes and positions: | |
449 | ||
450 | @defun set-frame-position frame left top | |
bfe721d1 KH |
451 | This function sets the position of the top left corner of @var{frame} to |
452 | @var{left} and @var{top}. These arguments are measured in pixels, and | |
453 | count from the top left corner of the screen. Negative parameter values | |
454 | count up or rightward from the top left corner of the screen. | |
d25390d0 RS |
455 | @end defun |
456 | ||
457 | @defun frame-height &optional frame | |
458 | @defunx frame-width &optional frame | |
459 | These functions return the height and width of @var{frame}, measured in | |
460 | characters. If you don't supply @var{frame}, they use the selected | |
461 | frame. | |
462 | @end defun | |
463 | ||
464 | @defun frame-pixel-height &optional frame | |
465 | @defunx frame-pixel-width &optional frame | |
466 | These functions return the height and width of @var{frame}, measured in | |
467 | pixels. If you don't supply @var{frame}, they use the selected frame. | |
468 | @end defun | |
469 | ||
470 | @defun frame-char-height &optional frame | |
471 | @defunx frame-char-width &optional frame | |
61cfa852 RS |
472 | These functions return the height and width of a character in |
473 | @var{frame}, measured in pixels. The values depend on the choice of | |
474 | font. If you don't supply @var{frame}, these functions use the selected | |
475 | frame. | |
d25390d0 RS |
476 | @end defun |
477 | ||
478 | @defun set-frame-size frame cols rows | |
fb9b5ab7 RS |
479 | This function sets the size of @var{frame}, measured in characters; |
480 | @var{cols} and @var{rows} specify the new width and height. | |
d25390d0 | 481 | |
fb9b5ab7 RS |
482 | To set the size based on values measured in pixels, use |
483 | @code{frame-char-height} and @code{frame-char-width} to convert | |
484 | them to units of characters. | |
d25390d0 RS |
485 | @end defun |
486 | ||
487 | The old-fashioned functions @code{set-screen-height} and | |
488 | @code{set-screen-width}, which were used to specify the height and width | |
489 | of the screen in Emacs versions that did not support multiple frames, | |
490 | are still usable. They apply to the selected frame. @xref{Screen | |
491 | Size}. | |
492 | ||
493 | @defun x-parse-geometry geom | |
494 | @cindex geometry specification | |
495 | The function @code{x-parse-geometry} converts a standard X windows | |
61cfa852 | 496 | geometry string to an alist that you can use as part of the argument to |
d25390d0 RS |
497 | @code{make-frame}. |
498 | ||
499 | The alist describes which parameters were specified in @var{geom}, and | |
500 | gives the values specified for them. Each element looks like | |
501 | @code{(@var{parameter} . @var{value})}. The possible @var{parameter} | |
502 | values are @code{left}, @code{top}, @code{width}, and @code{height}. | |
503 | ||
22697dac KH |
504 | For the size parameters, the value must be an integer. The position |
505 | parameter names @code{left} and @code{top} are not totally accurate, | |
506 | because some values indicate the position of the right or bottom edges | |
507 | instead. These are the @var{value} possibilities for the position | |
508 | parameters: | |
509 | ||
510 | @table @asis | |
511 | @item an integer | |
512 | A positive integer relates the left edge or top edge of the window to | |
513 | the left or top edge of the screen. A negative integer relates the | |
514 | right or bottom edge of the window to the right or bottom edge of the | |
515 | screen. | |
516 | ||
bfe721d1 | 517 | @item @code{(+ @var{position})} |
22697dac KH |
518 | This specifies the position of the left or top edge of the window |
519 | relative to the left or top edge of the screen. The integer | |
520 | @var{position} may be positive or negative; a negative value specifies a | |
521 | position outside the screen. | |
522 | ||
bfe721d1 | 523 | @item @code{(- @var{position})} |
22697dac KH |
524 | This specifies the position of the right or bottom edge of the window |
525 | relative to the right or bottom edge of the screen. The integer | |
526 | @var{position} may be positive or negative; a negative value specifies a | |
527 | position outside the screen. | |
528 | @end table | |
529 | ||
530 | Here is an example: | |
531 | ||
bfe721d1 | 532 | @example |
d25390d0 | 533 | (x-parse-geometry "35x70+0-0") |
bfe721d1 KH |
534 | @result{} ((width . 35) (height . 70) |
535 | (left . 0) (top - 0)) | |
536 | @end example | |
d25390d0 RS |
537 | @end defun |
538 | ||
539 | @ignore | |
540 | New functions @code{set-frame-height} and @code{set-frame-width} set the | |
541 | size of a specified frame. The frame is the first argument; the size is | |
542 | the second. | |
543 | @end ignore | |
544 | ||
22697dac KH |
545 | @node Frame Titles |
546 | @section Frame Titles | |
547 | ||
548 | Every frame has a title; most window managers display the frame title at | |
549 | the top of the frame. You can specify an explicit title with the | |
550 | @code{name} frame property. But normally you don't specify this | |
551 | explicitly, and Emacs computes the title automatically. | |
552 | ||
553 | Emacs computes the frame title based on a template stored in the | |
554 | variable @code{frame-title-format}. | |
555 | ||
556 | @defvar frame-title-format | |
557 | This variable specifies how to compute a title for a frame | |
558 | when you have not explicitly specified one. | |
559 | ||
560 | The variable's value is actually a mode line construct, just like | |
561 | @code{mode-line-format}. @xref{Mode Line Data}. | |
562 | @end defvar | |
563 | ||
564 | @defvar icon-title-format | |
565 | This variable specifies how to compute the title for an iconified frame, | |
566 | when you have not explicitly specified the frame title. This title | |
567 | appears in the icon itself. | |
568 | @end defvar | |
569 | ||
570 | @defvar multiple-frames | |
571 | This variable is set automatically by Emacs. Its value is @code{t} when | |
572 | there are two or more frames (not counting minibuffer-only frames or | |
573 | invisible frames). The default value of @code{frame-title-format} uses | |
574 | @code{multiple-frames} so as to put the buffer name in the frame title | |
575 | only when there is more than one frame. | |
22697dac KH |
576 | @end defvar |
577 | ||
d25390d0 RS |
578 | @node Deleting Frames |
579 | @section Deleting Frames | |
580 | @cindex deletion of frames | |
581 | ||
582 | Frames remain potentially visible until you explicitly @dfn{delete} | |
583 | them. A deleted frame cannot appear on the screen, but continues to | |
584 | exist as a Lisp object until there are no references to it. There is no | |
585 | way to cancel the deletion of a frame aside from restoring a saved frame | |
586 | configuration (@pxref{Frame Configurations}); this is similar to the | |
587 | way windows behave. | |
588 | ||
589 | @deffn Command delete-frame &optional frame | |
590 | This function deletes the frame @var{frame}. By default, @var{frame} is | |
591 | the selected frame. | |
592 | @end deffn | |
593 | ||
594 | @defun frame-live-p frame | |
595 | The function @code{frame-live-p} returns non-@code{nil} if the frame | |
596 | @var{frame} has not been deleted. | |
597 | @end defun | |
598 | ||
22697dac | 599 | Some window managers provide a command to delete a window. These work |
eaac2be1 | 600 | by sending a special message to the program that operates the window. |
22697dac KH |
601 | When Emacs gets one of these commands, it generates a |
602 | @code{delete-frame} event, whose normal definition is a command that | |
603 | calls the function @code{delete-frame}. @xref{Misc Events}. | |
604 | ||
d25390d0 RS |
605 | @node Finding All Frames |
606 | @section Finding All Frames | |
607 | ||
608 | @defun frame-list | |
609 | The function @code{frame-list} returns a list of all the frames that | |
610 | have not been deleted. It is analogous to @code{buffer-list} for | |
611 | buffers. The list that you get is newly created, so modifying the list | |
612 | doesn't have any effect on the internals of Emacs. | |
613 | @end defun | |
614 | ||
615 | @defun visible-frame-list | |
616 | This function returns a list of just the currently visible frames. | |
22697dac KH |
617 | @xref{Visibility of Frames}. (Terminal frames always count as |
618 | ``visible'', even though only the selected one is actually displayed.) | |
d25390d0 RS |
619 | @end defun |
620 | ||
621 | @defun next-frame &optional frame minibuf | |
622 | The function @code{next-frame} lets you cycle conveniently through all | |
623 | the frames from an arbitrary starting point. It returns the ``next'' | |
624 | frame after @var{frame} in the cycle. If @var{frame} is omitted or | |
625 | @code{nil}, it defaults to the selected frame. | |
626 | ||
627 | The second argument, @var{minibuf}, says which frames to consider: | |
628 | ||
629 | @table @asis | |
630 | @item @code{nil} | |
631 | Exclude minibuffer-only frames. | |
632 | @item @code{visible} | |
633 | Consider all visible frames. | |
bfe721d1 KH |
634 | @item 0 |
635 | Consider all visible or iconified frames. | |
d25390d0 RS |
636 | @item a window |
637 | Consider only the frames using that particular window as their | |
638 | minibuffer. | |
639 | @item anything else | |
640 | Consider all frames. | |
641 | @end table | |
642 | @end defun | |
643 | ||
644 | @defun previous-frame &optional frame minibuf | |
645 | Like @code{next-frame}, but cycles through all frames in the opposite | |
646 | direction. | |
647 | @end defun | |
648 | ||
bfe721d1 KH |
649 | See also @code{next-window} and @code{previous-window}, in @ref{Cyclic |
650 | Window Ordering}. | |
651 | ||
d25390d0 RS |
652 | @node Frames and Windows |
653 | @section Frames and Windows | |
654 | ||
fb9b5ab7 RS |
655 | Each window is part of one and only one frame; you can get the frame |
656 | with @code{window-frame}. | |
d25390d0 RS |
657 | |
658 | @defun window-frame window | |
659 | This function returns the frame that @var{window} is on. | |
fb9b5ab7 RS |
660 | @end defun |
661 | ||
662 | All the non-minibuffer windows in a frame are arranged in a cyclic | |
663 | order. The order runs from the frame's top window, which is at the | |
664 | upper left corner, down and to the right, until it reaches the window at | |
665 | the lower right corner (always the minibuffer window, if the frame has | |
666 | one), and then it moves back to the top. | |
667 | ||
668 | @defun frame-top-window frame | |
669 | This returns the topmost, leftmost window of frame @var{frame}. | |
d25390d0 RS |
670 | @end defun |
671 | ||
672 | At any time, exactly one window on any frame is @dfn{selected within the | |
673 | frame}. The significance of this designation is that selecting the | |
674 | frame also selects this window. You can get the frame's current | |
675 | selected window with @code{frame-selected-window}. | |
676 | ||
677 | @defun frame-selected-window frame | |
61cfa852 | 678 | This function returns the window on @var{frame} that is selected within |
d25390d0 RS |
679 | @var{frame}. |
680 | @end defun | |
681 | ||
682 | Conversely, selecting a window for Emacs with @code{select-window} also | |
683 | makes that window selected within its frame. @xref{Selecting Windows}. | |
684 | ||
bfe721d1 KH |
685 | Another function that (usually) returns one of the windows in a frame is |
686 | @code{minibuffer-window}. @xref{Minibuffer Misc}. | |
687 | ||
d25390d0 RS |
688 | @node Minibuffers and Frames |
689 | @section Minibuffers and Frames | |
690 | ||
691 | Normally, each frame has its own minibuffer window at the bottom, which | |
692 | is used whenever that frame is selected. If the frame has a minibuffer, | |
693 | you can get it with @code{minibuffer-window} (@pxref{Minibuffer Misc}). | |
694 | ||
695 | However, you can also create a frame with no minibuffer. Such a frame | |
696 | must use the minibuffer window of some other frame. When you create the | |
bfe721d1 KH |
697 | frame, you can specify explicitly the minibuffer window to use (in some |
698 | other frame). If you don't, then the minibuffer is found in the frame | |
699 | which is the value of the variable @code{default-minibuffer-frame}. Its | |
700 | value should be a frame that does have a minibuffer. | |
d25390d0 RS |
701 | |
702 | If you use a minibuffer-only frame, you might want that frame to raise | |
703 | when you enter the minibuffer. If so, set the variable | |
704 | @code{minibuffer-auto-raise} to @code{t}. @xref{Raising and Lowering}. | |
705 | ||
22697dac KH |
706 | @defvar default-minibuffer-frame |
707 | This variable specifies the frame to use for the minibuffer window, by | |
bfe721d1 | 708 | default. It is always local to the current terminal and cannot be |
22697dac KH |
709 | buffer-local. @xref{Multiple Displays}. |
710 | @end defvar | |
711 | ||
d25390d0 RS |
712 | @node Input Focus |
713 | @section Input Focus | |
714 | @cindex input focus | |
715 | @cindex selected frame | |
716 | ||
717 | At any time, one frame in Emacs is the @dfn{selected frame}. The selected | |
718 | window always resides on the selected frame. | |
719 | ||
720 | @defun selected-frame | |
721 | This function returns the selected frame. | |
722 | @end defun | |
723 | ||
724 | The X server normally directs keyboard input to the X window that the | |
725 | mouse is in. Some window managers use mouse clicks or keyboard events | |
726 | to @dfn{shift the focus} to various X windows, overriding the normal | |
727 | behavior of the server. | |
728 | ||
729 | Lisp programs can switch frames ``temporarily'' by calling | |
730 | the function @code{select-frame}. This does not override the window | |
731 | manager; rather, it escapes from the window manager's control until | |
732 | that control is somehow reasserted. | |
733 | ||
22697dac KH |
734 | When using a text-only terminal, there is no window manager; therefore, |
735 | @code{switch-frame} is the only way to switch frames, and the effect | |
736 | lasts until overridden by a subsequent call to @code{switch-frame}. | |
737 | Only the selected terminal frame is actually displayed on the terminal. | |
738 | Each terminal screen except for the initial one has a number, and the | |
739 | number of the selected frame appears in the mode line after the word | |
bfe721d1 | 740 | @samp{Emacs} (@pxref{Mode Line Variables}). |
22697dac | 741 | |
d25390d0 RS |
742 | @c ??? This is not yet implemented properly. |
743 | @defun select-frame frame | |
744 | This function selects frame @var{frame}, temporarily disregarding the | |
22697dac KH |
745 | focus of the X server if any. The selection of @var{frame} lasts until |
746 | the next time the user does something to select a different frame, or | |
747 | until the next time this function is called. | |
d25390d0 RS |
748 | @end defun |
749 | ||
750 | Emacs cooperates with the X server and the window managers by arranging | |
751 | to select frames according to what the server and window manager ask | |
752 | for. It does so by generating a special kind of input event, called a | |
753 | @dfn{focus} event. The command loop handles a focus event by calling | |
1a426e9b | 754 | @code{handle-switch-frame}. @xref{Focus Events}. |
d25390d0 RS |
755 | |
756 | @deffn Command handle-switch-frame frame | |
757 | This function handles a focus event by selecting frame @var{frame}. | |
758 | ||
759 | Focus events normally do their job by invoking this command. | |
760 | Don't call it for any other reason. | |
761 | @end deffn | |
762 | ||
763 | @defun redirect-frame-focus frame focus-frame | |
764 | This function redirects focus from @var{frame} to @var{focus-frame}. | |
61cfa852 | 765 | This means that @var{focus-frame} will receive subsequent keystrokes |
d25390d0 RS |
766 | intended for @var{frame}. After such an event, the value of |
767 | @code{last-event-frame} will be @var{focus-frame}. Also, switch-frame | |
768 | events specifying @var{frame} will instead select @var{focus-frame}. | |
769 | ||
770 | If @var{focus-frame} is @code{nil}, that cancels any existing | |
771 | redirection for @var{frame}, which therefore once again receives its own | |
772 | events. | |
773 | ||
774 | One use of focus redirection is for frames that don't have minibuffers. | |
775 | These frames use minibuffers on other frames. Activating a minibuffer | |
776 | on another frame redirects focus to that frame. This puts the focus on | |
777 | the minibuffer's frame, where it belongs, even though the mouse remains | |
61cfa852 | 778 | in the frame that activated the minibuffer. |
d25390d0 RS |
779 | |
780 | Selecting a frame can also change focus redirections. Selecting frame | |
781 | @code{bar}, when @code{foo} had been selected, changes any redirections | |
782 | pointing to @code{foo} so that they point to @code{bar} instead. This | |
783 | allows focus redirection to work properly when the user switches from | |
784 | one frame to another using @code{select-window}. | |
785 | ||
786 | This means that a frame whose focus is redirected to itself is treated | |
787 | differently from a frame whose focus is not redirected. | |
788 | @code{select-frame} affects the former but not the latter. | |
789 | ||
790 | The redirection lasts until @code{redirect-frame-focus} is called to | |
791 | change it. | |
792 | @end defun | |
793 | ||
794 | @node Visibility of Frames | |
795 | @section Visibility of Frames | |
796 | @cindex visible frame | |
797 | @cindex invisible frame | |
798 | @cindex iconified frame | |
799 | @cindex frame visibility | |
800 | ||
bfe721d1 | 801 | An X window frame may be @dfn{visible}, @dfn{invisible}, or |
22697dac KH |
802 | @dfn{iconified}. If it is visible, you can see its contents. If it is |
803 | iconified, the frame's contents do not appear on the screen, but an icon | |
804 | does. If the frame is invisible, it doesn't show on the screen, not | |
805 | even as an icon. | |
806 | ||
807 | Visibility is meaningless for terminal frames, since only the selected | |
808 | one is actually displayed in any case. | |
d25390d0 RS |
809 | |
810 | @deffn Command make-frame-visible &optional frame | |
811 | This function makes frame @var{frame} visible. If you omit @var{frame}, | |
812 | it makes the selected frame visible. | |
813 | @end deffn | |
814 | ||
815 | @deffn Command make-frame-invisible &optional frame | |
816 | This function makes frame @var{frame} invisible. If you omit | |
817 | @var{frame}, it makes the selected frame invisible. | |
818 | @end deffn | |
819 | ||
820 | @deffn Command iconify-frame &optional frame | |
821 | This function iconifies frame @var{frame}. If you omit @var{frame}, it | |
822 | iconifies the selected frame. | |
823 | @end deffn | |
824 | ||
825 | @defun frame-visible-p frame | |
826 | This returns the visibility status of frame @var{frame}. The value is | |
827 | @code{t} if @var{frame} is visible, @code{nil} if it is invisible, and | |
828 | @code{icon} if it is iconified. | |
829 | @end defun | |
830 | ||
831 | The visibility status of a frame is also available as a frame | |
832 | parameter. You can read or change it as such. @xref{X Frame | |
833 | Parameters}. | |
834 | ||
22697dac KH |
835 | The user can iconify and deiconify frames with the window manager. |
836 | This happens below the level at which Emacs can exert any control, but | |
837 | Emacs does provide events that you can use to keep track of such | |
838 | changes. @xref{Misc Events}. | |
839 | ||
d25390d0 RS |
840 | @node Raising and Lowering |
841 | @section Raising and Lowering Frames | |
842 | ||
843 | The X Window System uses a desktop metaphor. Part of this metaphor is | |
844 | the idea that windows are stacked in a notional third dimension | |
845 | perpendicular to the screen surface, and thus ordered from ``highest'' | |
846 | to ``lowest''. Where two windows overlap, the one higher up covers the | |
847 | one underneath. Even a window at the bottom of the stack can be seen if | |
848 | no other window overlaps it. | |
849 | ||
850 | @cindex raising a frame | |
851 | @cindex lowering a frame | |
852 | A window's place in this ordering is not fixed; in fact, users tend to | |
853 | change the order frequently. @dfn{Raising} a window means moving it | |
854 | ``up'', to the top of the stack. @dfn{Lowering} a window means moving | |
855 | it to the bottom of the stack. This motion is in the notional third | |
856 | dimension only, and does not change the position of the window on the | |
857 | screen. | |
858 | ||
859 | You can raise and lower Emacs's X windows with these functions: | |
860 | ||
22697dac | 861 | @deffn Command raise-frame frame |
d25390d0 | 862 | This function raises frame @var{frame}. |
22697dac | 863 | @end deffn |
d25390d0 | 864 | |
22697dac | 865 | @deffn Command lower-frame frame |
d25390d0 | 866 | This function lowers frame @var{frame}. |
22697dac | 867 | @end deffn |
d25390d0 RS |
868 | |
869 | @defopt minibuffer-auto-raise | |
870 | If this is non-@code{nil}, activation of the minibuffer raises the frame | |
871 | that the minibuffer window is in. | |
872 | @end defopt | |
873 | ||
874 | You can also enable auto-raise (raising automatically when a frame is | |
875 | selected) or auto-lower (lowering automatically when it is deselected) | |
876 | for any frame using frame parameters. @xref{X Frame Parameters}. | |
877 | ||
878 | @node Frame Configurations | |
879 | @section Frame Configurations | |
880 | @cindex frame configuration | |
881 | ||
882 | A @dfn{frame configuration} records the current arrangement of frames, | |
883 | all their properties, and the window configuration of each one. | |
884 | ||
885 | @defun current-frame-configuration | |
61cfa852 | 886 | This function returns a frame configuration list that describes |
d25390d0 RS |
887 | the current arrangement of frames and their contents. |
888 | @end defun | |
889 | ||
890 | @defun set-frame-configuration configuration | |
891 | This function restores the state of frames described in | |
892 | @var{configuration}. | |
893 | @end defun | |
894 | ||
895 | @node Mouse Tracking | |
896 | @section Mouse Tracking | |
897 | @cindex mouse tracking | |
898 | @cindex tracking the mouse | |
899 | ||
61cfa852 | 900 | Sometimes it is useful to @dfn{track} the mouse, which means to display |
d25390d0 RS |
901 | something to indicate where the mouse is and move the indicator as the |
902 | mouse moves. For efficient mouse tracking, you need a way to wait until | |
903 | the mouse actually moves. | |
904 | ||
905 | The convenient way to track the mouse is to ask for events to represent | |
906 | mouse motion. Then you can wait for motion by waiting for an event. In | |
907 | addition, you can easily handle any other sorts of events that may | |
908 | occur. That is useful, because normally you don't want to track the | |
909 | mouse forever---only until some other event, such as the release of a | |
910 | button. | |
911 | ||
912 | @defspec track-mouse body@dots{} | |
913 | Execute @var{body}, meanwhile generating input events for mouse motion. | |
914 | The code in @var{body} can read these events with @code{read-event} or | |
915 | @code{read-key-sequence}. @xref{Motion Events}, for the format of mouse | |
916 | motion events. | |
917 | ||
918 | The value of @code{track-mouse} is that of the last form in @var{body}. | |
919 | @end defspec | |
920 | ||
921 | The usual purpose of tracking mouse motion is to indicate on the screen | |
922 | the consequences of pushing or releasing a button at the current | |
923 | position. | |
924 | ||
bfe721d1 KH |
925 | In many cases, you can avoid the need to track the mouse by using |
926 | the @code{mouse-face} text property (@pxref{Special Properties}). | |
927 | That works at a much lower level and runs more smoothly than | |
928 | Lisp-level mouse tracking. | |
929 | ||
d25390d0 RS |
930 | @ignore |
931 | @c These are not implemented yet. | |
932 | ||
933 | These functions change the screen appearance instantaneously. The | |
934 | effect is transient, only until the next ordinary Emacs redisplay. That | |
935 | is ok for mouse tracking, since it doesn't make sense for mouse tracking | |
936 | to change the text, and the body of @code{track-mouse} normally reads | |
937 | the events itself and does not do redisplay. | |
938 | ||
939 | @defun x-contour-region window beg end | |
940 | This function draws lines to make a box around the text from @var{beg} | |
941 | to @var{end}, in window @var{window}. | |
942 | @end defun | |
943 | ||
944 | @defun x-uncontour-region window beg end | |
945 | This function erases the lines that would make a box around the text | |
946 | from @var{beg} to @var{end}, in window @var{window}. Use it to remove | |
947 | a contour that you previously made by calling @code{x-contour-region}. | |
948 | @end defun | |
949 | ||
950 | @defun x-draw-rectangle frame left top right bottom | |
951 | This function draws a hollow rectangle on frame @var{frame} with the | |
952 | specified edge coordinates, all measured in pixels from the inside top | |
953 | left corner. It uses the cursor color, the one used for indicating the | |
954 | location of point. | |
955 | @end defun | |
956 | ||
957 | @defun x-erase-rectangle frame left top right bottom | |
958 | This function erases a hollow rectangle on frame @var{frame} with the | |
959 | specified edge coordinates, all measured in pixels from the inside top | |
960 | left corner. Erasure means redrawing the text and background that | |
961 | normally belong in the specified rectangle. | |
962 | @end defun | |
963 | @end ignore | |
964 | ||
965 | @node Mouse Position | |
966 | @section Mouse Position | |
967 | @cindex mouse position | |
968 | @cindex position of mouse | |
969 | ||
970 | The functions @code{mouse-position} and @code{set-mouse-position} | |
971 | give access to the current position of the mouse. | |
972 | ||
973 | @defun mouse-position | |
974 | This function returns a description of the position of the mouse. The | |
975 | value looks like @code{(@var{frame} @var{x} . @var{y})}, where @var{x} | |
fb9b5ab7 RS |
976 | and @var{y} are integers giving the position in characters relative to |
977 | the top left corner of the inside of @var{frame}. | |
d25390d0 RS |
978 | @end defun |
979 | ||
980 | @defun set-mouse-position frame x y | |
981 | This function @dfn{warps the mouse} to position @var{x}, @var{y} in | |
982 | frame @var{frame}. The arguments @var{x} and @var{y} are integers, | |
fb9b5ab7 | 983 | giving the position in characters relative to the top left corner of the |
d25390d0 | 984 | inside of @var{frame}. |
fb9b5ab7 | 985 | @end defun |
d25390d0 | 986 | |
fb9b5ab7 RS |
987 | @defun mouse-pixel-position |
988 | This function is like @code{mouse-position} except that it returns | |
989 | coordinates in units of pixels rather than units of characters. | |
990 | @end defun | |
991 | ||
992 | @defun set-mouse-pixel-position frame x y | |
993 | This function warps the mouse like @code{set-mouse-position} except that | |
994 | @var{x} and @var{y} are in units of pixels rather than units of | |
995 | characters. These coordinates are not required to be within the frame. | |
d25390d0 RS |
996 | @end defun |
997 | ||
998 | @need 3000 | |
999 | ||
1000 | @node Pop-Up Menus | |
1001 | @section Pop-Up Menus | |
1002 | ||
22697dac KH |
1003 | When using X windows, a Lisp program can pop up a menu which the |
1004 | user can choose from with the mouse. | |
1005 | ||
d25390d0 RS |
1006 | @defun x-popup-menu position menu |
1007 | This function displays a pop-up menu and returns an indication of | |
1008 | what selection the user makes. | |
1009 | ||
1010 | The argument @var{position} specifies where on the screen to put the | |
1011 | menu. It can be either a mouse button event (which says to put the menu | |
1012 | where the user actuated the button) or a list of this form: | |
1013 | ||
1014 | @example | |
1015 | ((@var{xoffset} @var{yoffset}) @var{window}) | |
1016 | @end example | |
1017 | ||
1018 | @noindent | |
fb9b5ab7 RS |
1019 | where @var{xoffset} and @var{yoffset} are coordinates, measured in |
1020 | pixels, counting from the top left corner of @var{window}'s frame. | |
d25390d0 RS |
1021 | |
1022 | If @var{position} is @code{t}, it means to use the current mouse | |
1023 | position. If @var{position} is @code{nil}, it means to precompute the | |
1024 | key binding equivalents for the keymaps specified in @var{menu}, | |
1025 | without actually displaying or popping up the menu. | |
1026 | ||
1027 | The argument @var{menu} says what to display in the menu. It can be a | |
1028 | keymap or a list of keymaps (@pxref{Menu Keymaps}). Alternatively, it | |
1029 | can have the following form: | |
1030 | ||
1031 | @example | |
1032 | (@var{title} @var{pane1} @var{pane2}...) | |
1033 | @end example | |
1034 | ||
1035 | @noindent | |
1036 | where each pane is a list of form | |
1037 | ||
1038 | @example | |
bfe721d1 | 1039 | (@var{title} (@var{line} . @var{item})...) |
d25390d0 RS |
1040 | @end example |
1041 | ||
1042 | Each @var{line} should be a string, and each @var{item} should be the | |
1043 | value to return if that @var{line} is chosen. | |
1044 | @end defun | |
1045 | ||
2368fc6f | 1046 | @strong{Usage note:} Don't use @code{x-popup-menu} to display a menu if |
d25390d0 RS |
1047 | a prefix key with a menu keymap would do the job. If you use a menu |
1048 | keymap to implement a menu, @kbd{C-h c} and @kbd{C-h a} can see the | |
1049 | individual items in that menu and provide help for them. If instead you | |
1050 | implement the menu by defining a command that calls @code{x-popup-menu}, | |
1051 | the help facilities cannot know what happens inside that command, so | |
2368fc6f RS |
1052 | they cannot give any help for the menu's items. |
1053 | ||
1054 | The menu bar mechanism, which lets you switch between submenus by | |
1055 | moving the mouse, cannot look within the definition of a command to see | |
1056 | that it calls @code{x-popup-menu}. Therefore, if you try to implement a | |
1057 | submenu using @code{x-popup-menu}, it cannot work with the menu bar in | |
1058 | an integrated fashion. This is why all menu bar submenus are | |
1059 | implemented with menu keymaps within the parent menu, and never with | |
1060 | @code{x-popup-menu}. @xref{Menu Bar}, | |
1061 | ||
1062 | If you want a menu bar submenu to have contents that vary, you should | |
1063 | still use a menu keymap to implement it. To make the contents vary, add | |
1064 | a hook function to @code{menu-bar-update-hook} to update the contents of | |
1065 | the menu keymap as necessary. | |
d25390d0 RS |
1066 | |
1067 | @node Dialog Boxes | |
1068 | @section Dialog Boxes | |
1069 | @cindex dialog boxes | |
1070 | ||
1071 | A dialog box is a variant of a pop-up menu. It looks a little | |
1072 | different (if Emacs uses an X toolkit), it always appears in the center | |
1073 | of a frame, and it has just one level and one pane. The main use of | |
1074 | dialog boxes is for asking questions that the user can answer with | |
1075 | ``yes'', ``no'', and a few other alternatives. The functions | |
1076 | @code{y-or-n-p} and @code{yes-or-no-p} use dialog boxes instead of the | |
1077 | keyboard, when called from commands invoked by mouse clicks. | |
1078 | ||
1079 | @defun x-popup-dialog position contents | |
1080 | This function displays a pop-up dialog box and returns an indication of | |
1081 | what selection the user makes. The argument @var{contents} specifies | |
1082 | the alternatives to offer; it has this format: | |
1083 | ||
1084 | @example | |
fb9b5ab7 | 1085 | (@var{title} (@var{string} . @var{value})@dots{}) |
d25390d0 RS |
1086 | @end example |
1087 | ||
1088 | @noindent | |
1089 | which looks like the list that specifies a single pane for | |
1090 | @code{x-popup-menu}. | |
1091 | ||
fb9b5ab7 RS |
1092 | The return value is @var{value} from the chosen alternative. |
1093 | ||
1094 | An element of the list may be just a string instead of a cons cell | |
1095 | @code{(@var{string} . @var{value})}. That makes a box that cannot | |
1096 | be selected. | |
1097 | ||
1098 | If @code{nil} appears in the list, it separates the left-hand items from | |
1099 | the right-hand items; items that precede the @code{nil} appear on the | |
1100 | left, and items that follow the @code{nil} appear on the right. If you | |
1101 | don't include a @code{nil} in the list, then approximately half the | |
1102 | items appear on each side. | |
1103 | ||
d25390d0 RS |
1104 | Dialog boxes always appear in the center of a frame; the argument |
1105 | @var{position} specifies which frame. The possible values are as in | |
1106 | @code{x-popup-menu}, but the precise coordinates don't matter; only the | |
1107 | frame matters. | |
fb9b5ab7 RS |
1108 | |
1109 | If your Emacs executable does not use an X toolkit, then it cannot | |
1110 | display a real dialog box; so instead it displays the same items in a | |
1111 | pop-up menu in the center of the frame. | |
d25390d0 RS |
1112 | @end defun |
1113 | ||
bd998259 RS |
1114 | @node Pointer Shapes |
1115 | @section Pointer Shapes | |
1116 | @cindex pointer shape | |
1117 | @cindex mouse pointer shape | |
1118 | ||
22697dac KH |
1119 | These variables specify which shape to use for the mouse pointer in |
1120 | various situations: | |
bd998259 RS |
1121 | |
1122 | @table @code | |
1123 | @item x-pointer-shape | |
1124 | @vindex x-pointer-shape | |
1125 | This variable specifies the pointer shape to use ordinarily in the Emacs | |
1126 | frame. | |
1127 | ||
1128 | @item x-sensitive-text-pointer-shape | |
1129 | @vindex x-sensitive-text-pointer-shape | |
1130 | This variable specifies the pointer shape to use when the mouse | |
1131 | is over mouse-sensitive text. | |
1132 | @end table | |
1133 | ||
1134 | These variables affect newly created frames. They do not normally | |
1135 | affect existing frames; however, if you set the mouse color of a frame, | |
1136 | that also updates its pointer shapes based on the current values of | |
1137 | these variables. @xref{X Frame Parameters}. | |
1138 | ||
1139 | The values you can use, to specify either of these pointer shapes, are | |
1140 | defined in the file @file{lisp/x-win.el}. Use @kbd{M-x apropos | |
1141 | @key{RET} x-pointer @key{RET}} to see a list of them. | |
1142 | ||
d25390d0 RS |
1143 | @node X Selections |
1144 | @section X Selections | |
1145 | @cindex selection (for X windows) | |
1146 | ||
1147 | The X server records a set of @dfn{selections} which permit transfer of | |
1148 | data between application programs. The various selections are | |
1149 | distinguished by @dfn{selection types}, represented in Emacs by | |
1150 | symbols. X clients including Emacs can read or set the selection for | |
1151 | any given type. | |
1152 | ||
1153 | @defun x-set-selection type data | |
1154 | This function sets a ``selection'' in the X server. It takes two | |
1155 | arguments: a selection type @var{type}, and the value to assign to it, | |
1156 | @var{data}. If @var{data} is @code{nil}, it means to clear out the | |
1157 | selection. Otherwise, @var{data} may be a string, a symbol, an integer | |
1158 | (or a cons of two integers or list of two integers), an overlay, or a | |
1159 | cons of two markers pointing to the same buffer. An overlay or a pair | |
1160 | of markers stands for text in the overlay or between the markers. | |
1161 | ||
1162 | The data may also be a vector of valid non-vector selection values. | |
1163 | ||
1164 | Each possible @var{type} has its own selection value, which changes | |
1165 | independently. The usual values of @var{type} are @code{PRIMARY} and | |
1166 | @code{SECONDARY}; these are symbols with upper-case names, in accord | |
1167 | with X Window System conventions. The default is @code{PRIMARY}. | |
1168 | @end defun | |
1169 | ||
61cfa852 | 1170 | @defun x-get-selection &optional type data-type |
d25390d0 RS |
1171 | This function accesses selections set up by Emacs or by other X |
1172 | clients. It takes two optional arguments, @var{type} and | |
1173 | @var{data-type}. The default for @var{type}, the selection type, is | |
1174 | @code{PRIMARY}. | |
1175 | ||
1176 | The @var{data-type} argument specifies the form of data conversion to | |
1177 | use, to convert the raw data obtained from another X client into Lisp | |
1178 | data. Meaningful values include @code{TEXT}, @code{STRING}, | |
1179 | @code{TARGETS}, @code{LENGTH}, @code{DELETE}, @code{FILE_NAME}, | |
1180 | @code{CHARACTER_POSITION}, @code{LINE_NUMBER}, @code{COLUMN_NUMBER}, | |
1181 | @code{OWNER_OS}, @code{HOST_NAME}, @code{USER}, @code{CLASS}, | |
1182 | @code{NAME}, @code{ATOM}, and @code{INTEGER}. (These are symbols with | |
1183 | upper-case names in accord with X conventions.) The default for | |
1184 | @var{data-type} is @code{STRING}. | |
1185 | @end defun | |
1186 | ||
1187 | @cindex cut buffer | |
1188 | The X server also has a set of numbered @dfn{cut buffers} which can | |
1189 | store text or other data being moved between applications. Cut buffers | |
1190 | are considered obsolete, but Emacs supports them for the sake of X | |
1191 | clients that still use them. | |
1192 | ||
1193 | @defun x-get-cut-buffer n | |
1194 | This function returns the contents of cut buffer number @var{n}. | |
1195 | @end defun | |
1196 | ||
1197 | @defun x-set-cut-buffer string | |
1198 | This function stores @var{string} into the first cut buffer (cut buffer | |
1199 | 0), moving the other values down through the series of cut buffers, much | |
1200 | like the way successive kills in Emacs move down the kill ring. | |
1201 | @end defun | |
1202 | ||
bfe721d1 KH |
1203 | @node Color Names |
1204 | @section Color Names | |
d25390d0 | 1205 | |
a3431be8 | 1206 | @defun x-color-defined-p color &optional frame |
fed7c77a | 1207 | This function reports whether a color name is meaningful. It returns |
a3431be8 RS |
1208 | @code{t} if so; otherwise, @code{nil}. The argument @var{frame} says |
1209 | which frame's display to ask about; if @var{frame} is omitted or | |
1210 | @code{nil}, the selected frame is used. | |
d25390d0 | 1211 | |
fed7c77a RS |
1212 | Note that this does not tell you whether the display you are using |
1213 | really supports that color. You can ask for any defined color on any | |
1214 | kind of display, and you will get some result---that is how the X server | |
1215 | works. Here's an approximate way to test whether your display supports | |
1216 | the color @var{color}: | |
1217 | ||
1218 | @example | |
a3431be8 RS |
1219 | (defun x-color-supported-p (color &optional frame) |
1220 | (and (x-color-defined-p color frame) | |
1221 | (or (x-display-color-p frame) | |
fed7c77a | 1222 | (member color '("black" "white")) |
a3431be8 | 1223 | (and (> (x-display-planes frame) 1) |
fed7c77a RS |
1224 | (equal color "gray"))))) |
1225 | @end example | |
1226 | @end defun | |
1227 | ||
a3431be8 | 1228 | @defun x-color-values color &optional frame |
fed7c77a RS |
1229 | This function returns a value that describes what @var{color} should |
1230 | ideally look like. If @var{color} is defined, the value is a list of | |
1231 | three integers, which give the amount of red, the amount of green, and | |
1232 | the amount of blue. Each integer ranges in principle from 0 to 65535, | |
1233 | but in practice no value seems to be above 65280. If @var{color} is not | |
1234 | defined, the value is @code{nil}. | |
1235 | ||
1236 | @example | |
1237 | (x-color-values "black") | |
1238 | @result{} (0 0 0) | |
1239 | (x-color-values "white") | |
1240 | @result{} (65280 65280 65280) | |
1241 | (x-color-values "red") | |
1242 | @result{} (65280 0 0) | |
1243 | (x-color-values "pink") | |
1244 | @result{} (65280 49152 51968) | |
1245 | (x-color-values "hungry") | |
1246 | @result{} nil | |
1247 | @end example | |
a3431be8 RS |
1248 | |
1249 | The color values are returned for @var{frame}'s display. If @var{frame} | |
1250 | is omitted or @code{nil}, the information is return for the selected | |
1251 | frame's display. | |
d25390d0 RS |
1252 | @end defun |
1253 | ||
d25390d0 RS |
1254 | @node Resources |
1255 | @section X Resources | |
1256 | ||
bfe721d1 | 1257 | @defun x-get-resource attribute class &optional component subclass |
d25390d0 RS |
1258 | The function @code{x-get-resource} retrieves a resource value from the X |
1259 | Windows defaults database. | |
1260 | ||
1261 | Resources are indexed by a combination of a @dfn{key} and a @dfn{class}. | |
1262 | This function searches using a key of the form | |
61cfa852 | 1263 | @samp{@var{instance}.@var{attribute}} (where @var{instance} is the name |
bfe721d1 KH |
1264 | under which Emacs was invoked), and using @samp{Emacs.@var{class}} as |
1265 | the class. | |
d25390d0 RS |
1266 | |
1267 | The optional arguments @var{component} and @var{subclass} add to the key | |
1268 | and the class, respectively. You must specify both of them or neither. | |
1269 | If you specify them, the key is | |
1270 | @samp{@var{instance}.@var{component}.@var{attribute}}, and the class is | |
bfe721d1 | 1271 | @samp{Emacs.@var{class}.@var{subclass}}. |
d25390d0 RS |
1272 | @end defun |
1273 | ||
bfe721d1 | 1274 | @xref{Resources X,, X Resources, emacs, The GNU Emacs Manual}. |
d25390d0 RS |
1275 | |
1276 | @node Server Data | |
1277 | @section Data about the X Server | |
1278 | ||
1a426e9b RS |
1279 | This section describes functions you can use to get information about |
1280 | the capabilities and origin of an X display that Emacs is using. Each | |
1281 | of these functions lets you specify the display you are interested in: | |
1282 | the @var{display} argument can be either a display name, or a frame | |
1283 | (meaning use the display that frame is on). If you omit the | |
1284 | @var{display} argument, or specify @code{nil}, that means to use the | |
1285 | selected frame's display. | |
22697dac KH |
1286 | |
1287 | @defun x-display-screens &optional display | |
1288 | This function returns the number of screens associated with the display. | |
d25390d0 RS |
1289 | @end defun |
1290 | ||
22697dac KH |
1291 | @defun x-server-version &optional display |
1292 | This function returns the list of version numbers of the X server | |
1293 | running the display. | |
d25390d0 RS |
1294 | @end defun |
1295 | ||
22697dac KH |
1296 | @defun x-server-vendor &optional display |
1297 | This function returns the vendor that provided the X server software. | |
d25390d0 RS |
1298 | @end defun |
1299 | ||
22697dac KH |
1300 | @defun x-display-pixel-height &optional display |
1301 | This function returns the height of the screen in pixels. | |
d25390d0 RS |
1302 | @end defun |
1303 | ||
22697dac KH |
1304 | @defun x-display-mm-height &optional display |
1305 | This function returns the height of the screen in millimeters. | |
d25390d0 RS |
1306 | @end defun |
1307 | ||
22697dac KH |
1308 | @defun x-display-pixel-width &optional display |
1309 | This function returns the width of the screen in pixels. | |
d25390d0 RS |
1310 | @end defun |
1311 | ||
22697dac KH |
1312 | @defun x-display-mm-width &optional display |
1313 | This function returns the width of the screen in millimeters. | |
d25390d0 RS |
1314 | @end defun |
1315 | ||
22697dac KH |
1316 | @defun x-display-backing-store &optional display |
1317 | This function returns the backing store capability of the screen. | |
d25390d0 RS |
1318 | Values can be the symbols @code{always}, @code{when-mapped}, or |
1319 | @code{not-useful}. | |
1320 | @end defun | |
1321 | ||
22697dac KH |
1322 | @defun x-display-save-under &optional display |
1323 | This function returns non-@code{nil} if the display supports the | |
d25390d0 RS |
1324 | SaveUnder feature. |
1325 | @end defun | |
1326 | ||
22697dac KH |
1327 | @defun x-display-planes &optional display |
1328 | This function returns the number of planes the display supports. | |
d25390d0 RS |
1329 | @end defun |
1330 | ||
22697dac KH |
1331 | @defun x-display-visual-class &optional display |
1332 | This function returns the visual class for the screen. The value is one | |
1333 | of the symbols @code{static-gray}, @code{gray-scale}, | |
d25390d0 RS |
1334 | @code{static-color}, @code{pseudo-color}, @code{true-color}, and |
1335 | @code{direct-color}. | |
1336 | @end defun | |
1337 | ||
22697dac KH |
1338 | @defun x-display-grayscale-p &optional display |
1339 | This function returns @code{t} if the screen can display shades of gray. | |
1340 | @end defun | |
1341 | ||
1342 | @defun x-display-color-p &optional display | |
1343 | This function returns @code{t} if the screen is a color screen. | |
d25390d0 RS |
1344 | @end defun |
1345 | ||
22697dac KH |
1346 | @defun x-display-color-cells &optional display |
1347 | This function returns the number of color cells the screen supports. | |
d25390d0 RS |
1348 | @end defun |
1349 | ||
1350 | @ignore | |
1351 | @defvar x-no-window-manager | |
1352 | This variable's value is is @code{t} if no X window manager is in use. | |
1353 | @end defvar | |
1354 | @end ignore | |
1355 | ||
1356 | @ignore | |
1357 | @item | |
1358 | The functions @code{x-pixel-width} and @code{x-pixel-height} return the | |
1359 | width and height of an X Window frame, measured in pixels. | |
d25390d0 | 1360 | @end ignore |