1font(n) Tk Built-In Commands font(n)
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6
8 font - Create and inspect fonts.
9
11 font option ?arg arg ...?
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13
15 The font command provides several facilities for dealing with fonts,
16 such as defining named fonts and inspecting the actual attributes of a
17 font. The command has several different forms, determined by the first
18 argument. The following forms are currently supported:
19 font actual font ?-displayof window? ?option? ?--? ?char?
21 Returns information about the actual attributes that are
22 obtained when font is used on window's display; the actual
23 attributes obtained may differ from the attributes requested due
24 to platform-dependent limitations, such as the availability of
25 font families and pointsizes. font is a font description; see
26 FONT DESCRIPTIONS below. If the window argument is omitted, it
27 defaults to the main window. If option is specified, returns
28 the value of that attribute; if it is omitted, the return value
29 is a list of all the attributes and their values. See FONT
30 OPTIONS below for a list of the possible attributes. If the
31 char argument is supplied, it must be a single character. The
32 font attributes returned will be those of the specific font used
33 to render that character, which will be different from the base
34 font if the base font does not contain the given character. If
35 char may be a hyphen, it should be preceded by -- to distinguish
36 it from a misspelled option.
37 font configure fontname ?option? ?value option value ...?
39 Query or modify the desired attributes for the named font called
40 fontname. If no option is specified, returns a list describing
41 all the options and their values for fontname. If a single
42 option is specified with no value, then returns the current
43 value of that attribute. If one or more option-value pairs are
44 specified, then the command modifies the given named font to
45 have the given values; in this case, all widgets using that font
46 will redisplay themselves using the new attributes for the font.
47 See FONT OPTIONS below for a list of the possible attributes.
48 font create ?fontname? ?option value ...?
50 Creates a new named font and returns its name. fontname speci‐
51 fies the name for the font; if it is omitted, then Tk generates
52 a new name of the form fontx, where x is an integer. There may
53 be any number of option-value pairs, which provide the desired
54 attributes for the new named font. See FONT OPTIONS below for a
55 list of the possible attributes.
56 font delete fontname ?fontname ...?
58 Delete the specified named fonts. If there are widgets using
59 the named font, the named font will not actually be deleted
60 until all the instances are released. Those widgets will con‐
61 tinue to display using the last known values for the named font.
62 If a deleted named font is subsequently recreated with another
63 call to font create, the widgets will use the new named font and
64 redisplay themselves using the new attributes of that font.
65 font families ?-displayof window?
67 The return value is a list of the case-insensitive names of all
68 font families that exist on window's display. If the window
69 argument is omitted, it defaults to the main window.
70 font measure font ?-displayof window? text
72 Measures the amount of space the string text would use in the
73 given font when displayed in window. font is a font descrip‐
74 tion; see FONT DESCRIPTIONS below. If the window argument is
75 omitted, it defaults to the main window. The return value is
76 the total width in pixels of text, not including the extra pix‐
77 els used by highly exaggerated characters such as cursive “f”.
78 If the string contains newlines or tabs, those characters are
79 not expanded or treated specially when measuring the string.
80 font metrics font ?-displayof window? ?option?
82 Returns information about the metrics (the font-specific data),
83 for font when it is used on window's display. font is a font
84 description; see FONT DESCRIPTIONS below. If the window argu‐
85 ment is omitted, it defaults to the main window. If option is
86 specified, returns the value of that metric; if it is omitted,
87 the return value is a list of all the metrics and their values.
88 See FONT METRICS below for a list of the possible metrics.
89 font names
91 The return value is a list of all the named fonts that are cur‐
92 rently defined.
93
95 The following formats are accepted as a font description anywhere font
96 is specified as an argument above; these same forms are also permitted
97 when specifying the -font option for widgets.
98 [1] fontname
100 The name of a named font, created using the font create command.
101 When a widget uses a named font, it is guaranteed that this will
102 never cause an error, as long as the named font exists, no mat‐
103 ter what potentially invalid or meaningless set of attributes
104 the named font has. If the named font cannot be displayed with
105 exactly the specified attributes, some other close font will be
106 substituted automatically.
107 [2] systemfont
109 The platform-specific name of a font, interpreted by the graph‐
110 ics server. This also includes, under X, an XLFD (see [4]) for
111 which a single “*” character was used to elide more than one
112 field in the middle of the name. See PLATFORM-SPECIFIC issues
113 for a list of the system fonts.
114 [3] family ?size? ?style? ?style ...?
116 A properly formed list whose first element is the desired font
117 family and whose optional second element is the desired size.
118 The interpretation of the size attribute follows the same rules
119 described for -size in FONT OPTIONS below. Any additional
120 optional arguments following the size are font styles. Possible
121 values for the style arguments are as follows:
122 normal bold roman italic underline overstrike
123 [4] X-font names (XLFD)
125 A Unix-centric font name of the form -foundry-fam‐
126 ily-weight-slant-setwidth-addstyle-pixel-point-resx-resy-spac‐
127 ing-width-charset-encoding. The “*” character may be used to
128 skip individual fields that the user does not care about. There
129 must be exactly one “*” for each field skipped, except that a
130 “*” at the end of the XLFD skips any remaining fields; the
131 shortest valid XLFD is simply “*”, signifying all fields as
132 defaults. Any fields that were skipped are given default val‐
133 ues. For compatibility, an XLFD always chooses a font of the
134 specified pixel size (not point size); although this interpreta‐
135 tion is not strictly correct, all existing applications using
136 XLFDs assumed that one “point” was in fact one pixel and would
137 display incorrectly (generally larger) if the correct size font
138 were actually used.
139 [5] option value ?option value ...?
141 A properly formed list of option-value pairs that specify the
142 desired attributes of the font, in the same format used when
143 defining a named font; see FONT OPTIONS below.
144 When font description font is used, the system attempts to parse the
146 description according to each of the above five rules, in the order
147 specified. Cases [1] and [2] must match the name of an existing named
148 font or of a system font. Cases [3], [4], and [5] are accepted on all
149 platforms and the closest available font will be used. In some situa‐
150 tions it may not be possible to find any close font (e.g., the font
151 family was a garbage value); in that case, some system-dependent
152 default font is chosen. If the font description does not match any of
153 the above patterns, an error is generated.
154
156 The following options are used by the font metrics command to query
157 font-specific data determined when the font was created. These proper‐
158 ties are for the whole font itself and not for individual characters
159 drawn in that font. In the following definitions, the “baseline” of a
160 font is the horizontal line where the bottom of most letters line up;
161 certain letters, such as lower-case “g” stick below the baseline.
162 -ascent
164 The amount in pixels that the tallest letter sticks up above the
165 baseline of the font, plus any extra blank space added by the
166 designer of the font.
167 -descent
169 The largest amount in pixels that any letter sticks down below
170 the baseline of the font, plus any extra blank space added by
171 the designer of the font.
172 -linespace
174 Returns how far apart vertically in pixels two lines of text
175 using the same font should be placed so that none of the charac‐
176 ters in one line overlap any of the characters in the other
177 line. This is generally the sum of the ascent above the base‐
178 line line plus the descent below the baseline.
179 -fixed
181 Returns a boolean flag that is “1” if this is a fixed-width
182 font, where each normal character is the same width as all the
183 other characters, or is “0” if this is a proportionally-spaced
184 font, where individual characters have different widths. The
185 widths of control characters, tab characters, and other non-
186 printing characters are not included when calculating this
187 value.
188
190 The following options are supported on all platforms, and are used when
191 constructing a named font or when specifying a font using style [5] as
192 above:
193 -family name
195 The case-insensitive font family name. Tk guarantees to support
196 the font families named Courier (a monospaced “typewriter”
197 font), Times (a serifed “newspaper” font), and Helvetica (a
198 sans-serif “European” font). The most closely matching native
199 font family will automatically be substituted when one of the
200 above font families is used. The name may also be the name of a
201 native, platform-specific font family; in that case it will work
202 as desired on one platform but may not display correctly on
203 other platforms. If the family is unspecified or unrecognized,
204 a platform-specific default font will be chosen.
205 -size size
207 The desired size of the font. If the size argument is a posi‐
208 tive number, it is interpreted as a size in points. If size is
209 a negative number, its absolute value is interpreted as a size
210 in pixels. If a font cannot be displayed at the specified size,
211 a nearby size will be chosen. If size is unspecified or zero, a
212 platform-dependent default size will be chosen.
213 Sizes should normally be specified in points so the application
215 will remain the same ruler size on the screen, even when chang‐
216 ing screen resolutions or moving scripts across platforms. How‐
217 ever, specifying pixels is useful in certain circumstances such
218 as when a piece of text must line up with respect to a fixed-
219 size bitmap. The mapping between points and pixels is set when
220 the application starts, based on properties of the installed
221 monitor, but it can be overridden by calling the tk scaling com‐
222 mand.
223 -weight weight
225 The nominal thickness of the characters in the font. The value
226 normal specifies a normal weight font, while bold specifies a
227 bold font. The closest available weight to the one specified
228 will be chosen. The default weight is normal.
229 -slant slant
231 The amount the characters in the font are slanted away from the
232 vertical. Valid values for slant are roman and italic. A roman
233 font is the normal, upright appearance of a font, while an
234 italic font is one that is tilted some number of degrees from
235 upright. The closest available slant to the one specified will
236 be chosen. The default slant is roman.
237 -underline boolean
239 The value is a boolean flag that specifies whether characters in
240 this font should be underlined. The default value for underline
241 is false.
242 -overstrike boolean
244 The value is a boolean flag that specifies whether a horizontal
245 line should be drawn through the middle of characters in this
246 font. The default value for overstrike is false.
247
249 The following named fonts are supported on all systems, and default to
250 values that match appropriate system defaults.
251 TkDefaultFont
253 This font is the default for all GUI items not otherwise speci‐
254 fied.
255 TkTextFont
257 This font should be used for user text in entry widgets, list‐
258 boxes etc.
259 TkFixedFont
261 This font is the standard fixed-width font.
262 TkMenuFont
264 This font is used for menu items.
265 TkHeadingFont
267 This font should be used for column headings in lists and
268 tables.
269 TkCaptionFont
271 This font should be used for window and dialog caption bars.
272 TkSmallCaptionFont
274 This font should be used for captions on contained windows or
275 tool dialogs.
276 TkIconFont
278 This font should be used for icon captions.
279 TkTooltipFont
281 This font should be used for tooltip windows (transient informa‐
282 tion windows).
283 It is not advised to change these fonts, as they may be modified by Tk
285 itself in response to system changes. Instead, make a copy of the font
286 and modify that.
287
289 The following system fonts are supported:
290 X Windows
292 All valid X font names, including those listed by xlsfonts(1),
293 are available.
294 MS Windows
296 The following fonts are supported, and are mapped to the user's
297 style defaults.
298 system ansi device systemfixed ansifixed oemfixed
299 Mac OS X
301 The following fonts are supported, and are mapped to the user's
302 style defaults.
303 system application menu
304 Additionally, the following named fonts provide access to the
306 Aqua theme fonts: systemSystemFont systemEmphasizedSystemFont
307 systemSmallSystemFontsystemSmallEmphasizedSystemFont systemAp‐
308 plicationFontsystemLabelFont systemViewsFont systemMenuTi‐
309 tleFont systemMenuItemFont systemMenuItemMarkFont systemMenu‐
310 ItemCmdKeyFontsystemWindowTitleFont systemPushButtonFontsystemU‐
311 tilityWindowTitleFont systemAlertHeaderFontsystemToolbarFont
312 systemMiniSystemFontsystemDetailSystemFont systemDetailEmpha‐
313 sizedSystemFont
314
316 Fill a text widget with lots of font demonstrators, one for every font
317 family installed on your system:
318 pack [text .t -wrap none] -fill both -expand 1
319 set count 0
320 set tabwidth 0
321 foreach family [lsort -dictionary [font families]] {
322 .t tag configure f[incr count] -font [list $family 10]
323 .t insert end ${family}:\t {} \
324 "This is a simple sampler\n" f$count
325 set w [font measure [.t cget -font] ${family}:]
326 if {$w+5 > $tabwidth} {
327 set tabwidth [expr {$w+5}]
328 .t configure -tabs $tabwidth
329 }
330 }
331
334 options(n)
335
338 font
339Tk 8.0 font(n)