1fontchooser(n) Tk Built-In Commands fontchooser(n)
2______________________________________________________________________________
6
8 fontchooser - control font selection dialog
9
11 tk fontchooser configure ?-option value -option value ...?
12 tk fontchooser show
14 tk fontchooser hide
16______________________________________________________________________________
17
19 The tk fontchooser command controls the Tk font selection dialog. It
20 uses the native platform font selection dialog where available, or a
21 dialog implemented in Tcl otherwise.
22 Unlike most of the other Tk dialog commands, tk fontchooser does not
24 return an immediate result, as on some platforms (Mac OS X) the stan‐
25 dard font dialog is modeless while on others (Windows) it is modal. To
26 accommodate this difference, all user interaction with the dialog will
27 be communicated to the caller via callbacks or virtual events.
28 The tk fontchooser command can have one of the following forms:
30 tk fontchooser configure ?-option value -option value ...?
32 Set or query one or more of the configurations options below
33 (analogous to Tk widget configuration).
34 tk fontchooser show
36 Show the font selection dialog. Depending on the platform, may
37 return immediately or only once the dialog has been withdrawn.
38 tk fontchooser hide
40 Hide the font selection dialog if it is visible and cause any
41 pending tk fontchooser show command to return.
42
44 -parent
45 Specifies/returns the logical parent window of the font selec‐
46 tion dialog (similar to the -parent option to other dialogs).
47 The font selection dialog is hidden if it is visible when the
48 parent window is destroyed.
49 -title Specifies/returns the title of the dialog. Has no effect on
51 platforms where the font selection dialog does not support ti‐
52 tles.
53 -font Specifies/returns the font that is currently selected in the di‐
55 alog if it is visible, or that will be initially selected when
56 the dialog is shown (if supported by the platform). Can be set
57 to the empty string to indicate that no font should be selected.
58 Fonts can be specified in any form given by the "FONT DESCRIP‐
59 TION" section in the font manual page.
60 -command
62 Specifies/returns the command prefix to be called when a font
63 selection has been made by the user. The command prefix is eval‐
64 uated at the global level after having the specification of the
65 selected font appended. On platforms where the font selection
66 dialog offers the user control of further font attributes (such
67 as color), additional key/value pairs may be appended before
68 evaluation. Can be set to the empty string to indicate that no
69 callback should be invoked. Fonts are specified by a list of
70 form [3] of the "FONT DESCRIPTION" section in the font manual
71 page (i.e. a list of the form {family size style ?style ...?}).
72 -visible
74 Read-only option that returns a boolean indicating whether the
75 font selection dialog is currently visible. Attempting to set
76 this option results in an error.
77
80 <<TkFontchooserVisibility>>
81 Sent to the dialog parent whenever the visibility of the font
82 selection dialog changes, both as a result of user action (e.g.
83 disposing of the dialog via OK/Cancel button or close box) and
84 of the tk fontchooser show/hide commands being called. Binding
85 scripts can determine the current visibility of the dialog by
86 querying the -visible configuration option.
87 <<TkFontchooserFontChanged>>
89 Sent to the dialog parent whenever the font selection dialog is
90 visible and the selected font changes, both as a result of user
91 action and of the -font configuration option being set. Binding
92 scripts can determine the currently selected font by querying
93 the -font configuration option.
94
96 Callers should not expect a result from tk fontchooser show and may not
97 assume that the dialog has been withdrawn or closed when the command
98 returns. All user interaction with the dialog is communicated to the
99 caller via the -command callback and the <<TkFontchooser*>> virtual
100 events. It is implementation dependent which exact user actions result
101 in the callback being called resp. the virtual events being sent. Where
102 an Apply or OK button is present in the dialog, that button will trig‐
103 ger the -command callback and <<TkFontchooserFontChanged>> virtual
104 event. On some implementations other user actions may also have that
105 effect; on Mac OS X for instance, the standard font selection dialog
106 immediately reflects all user choices to the caller.
107 In the presence of multiple widgets intended to be influenced by the
109 font selection dialog, care needs to be taken to correctly handle focus
110 changes: the font selected in the dialog should always match the cur‐
111 rent font of the widget with the focus, and the -command callback
112 should only act on the widget with the focus. The recommended practice
113 is to set font dialog -font and -command configuration options in
114 per-widget <FocusIn> handlers (and if necessary to unset them - i.e.
115 set to the empty string - in corresponding <FocusOut> handlers). This
116 is particularly important for implementers of library code using the
117 font selection dialog, to avoid conflicting with application code that
118 may also want to use the dialog.
119 Because the font selection dialog is application-global, in the pres‐
121 ence of multiple interpreters calling tk fontchooser, only the -command
122 callback set by the interpreter that most recently called tk
123 fontchooser configure or tk fontchooser show will be invoked in re‐
124 sponse to user action and only the -parent set by that interpreter will
125 receive <<TkFontchooser*>> virtual events.
126 The font dialog implementation may only store (and return) font actual
128 data as the value of the -font configuration option. This can be an is‐
129 sue when -font is set to a named font, if that font is subsequently
130 changed, the font dialog -font option needs to be set again to ensure
131 its selected font matches the new value of the named font.
132
134 proc fontchooserDemo {} {
135 wm title . "Font Chooser Demo"
136 tk fontchooser configure -parent .
137 button .b -command fontchooserToggle -takefocus 0
138 fontchooserVisibility .b
139 bind . <<TkFontchooserVisibility>> \
140 [list fontchooserVisibility .b]
141 foreach w {.t1 .t2} {
142 text $w -width 20 -height 4 -borderwidth 1 -relief solid
143 bind $w <FocusIn> [list fontchooserFocus $w]
144 $w insert end "Text Widget $w"
145 }
146 .t1 configure -font {Courier 14}
147 .t2 configure -font {Times 16}
148 pack .b .t1 .t2; focus .t1
149 }
150 proc fontchooserToggle {} {
151 tk fontchooser [expr {
152 [tk fontchooser configure -visible] ?
153 "hide" : "show"}]
154 }
155 proc fontchooserVisibility {w} {
156 $w configure -text [expr {
157 [tk fontchooser configure -visible] ?
158 "Hide Font Dialog" : "Show Font Dialog"}]
159 }
160 proc fontchooserFocus {w} {
161 tk fontchooser configure -font [$w cget -font] \
162 -command [list fontchooserFontSelection $w]
163 }
164 proc fontchooserFontSelection {w font args} {
165 $w configure -font [font actual $font]
166 }
167 fontchooserDemo
168
170 font(n), tk(n)
171
173 dialog, font, font selection, font chooser, font panel
174Tk fontchooser(n)