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fontchooser(n)		     Tk	Built-In Commands		fontchooser(n)

______________________________________________________________________________

NAME
       fontchooser - control font selection dialog

SYNOPSIS
       tk fontchooser configure	?-option value -option value ...?

       tk fontchooser show

       tk fontchooser hide
______________________________________________________________________________

DESCRIPTION
       The  tk	fontchooser  command controls the Tk font selection dialog. It
       uses the	native platform	font selection dialog where  available,	 or  a
       dialog implemented in Tcl otherwise.

       Unlike  most  of	 the other Tk dialog commands, tk fontchooser does not
       return an immediate result, as on some platforms	(Mac OS	X)  the	 stan-
       dard  font dialog is modeless while on others (Windows) it is modal. To
       accommodate this	difference, all	user interaction with the dialog  will
       be communicated to the caller via callbacks or virtual events.

       The tk fontchooser command can have one of the following	forms:

       tk fontchooser configure	?-option value -option value ...?
	      Set  or  query  one  or more of the configurations options below
	      (analogous to Tk widget configuration).

       tk fontchooser show
	      Show the font selection dialog. Depending	on the	platform,  may
	      return immediately or only once the dialog has been withdrawn.

       tk fontchooser hide
	      Hide  the	 font  selection dialog	if it is visible and cause any
	      pending tk fontchooser show command to return.

CONFIGURATION OPTIONS
       -parent
	      Specifies/returns	the logical parent window of the  font	selec-
	      tion  dialog  (similar  to the -parent option to other dialogs).
	      The font selection dialog	is hidden if it	is  visible  when  the
	      parent window is destroyed.

       -title Specifies/returns	 the  title  of	 the  dialog. Has no effect on
	      platforms	where the font selection dialog	does not  support  ti-
	      tles.

       -font  Specifies/returns	the font that is currently selected in the di-
	      alog if it is visible, or	that will be initially	selected  when
	      the  dialog  is shown (if	supported by the platform). Can	be set
	      to the empty string to indicate that no font should be selected.
	      Fonts  can  be specified in any form given by the	"FONT DESCRIP-
	      TION" section in the font	manual page.

       -command
	      Specifies/returns	the command prefix to be called	 when  a  font
	      selection	has been made by the user. The command prefix is eval-
	      uated at the global level	after having the specification of  the
	      selected	font  appended.	 On platforms where the	font selection
	      dialog offers the	user control of	further	font attributes	 (such
	      as  color),  additional  key/value  pairs	may be appended	before
	      evaluation. Can be set to	the empty string to indicate  that  no
	      callback	should	be  invoked.  Fonts are	specified by a list of
	      form [3] of the "FONT DESCRIPTION" section in  the  font	manual
	      page (i.e. a list	of the form {family size style ?style ...?}).

       -visible
	      Read-only	 option	 that returns a	boolean	indicating whether the
	      font selection dialog is currently visible.  Attempting  to  set
	      this option results in an	error.

VIRTUAL	EVENTS
       <<TkFontchooserVisibility>>
	      Sent  to	the  dialog parent whenever the	visibility of the font
	      selection	dialog changes,	both as	a result of user action	 (e.g.
	      disposing	 of  the dialog	via OK/Cancel button or	close box) and
	      of the tk	fontchooser show/hide commands being  called.  Binding
	      scripts  can  determine  the current visibility of the dialog by
	      querying the -visible configuration option.

       <<TkFontchooserFontChanged>>
	      Sent to the dialog parent	whenever the font selection dialog  is
	      visible  and the selected	font changes, both as a	result of user
	      action and of the	-font configuration option being set.  Binding
	      scripts  can  determine  the currently selected font by querying
	      the -font	configuration option.

NOTES
       Callers should not expect a result from tk fontchooser show and may not
       assume  that  the  dialog has been withdrawn or closed when the command
       returns.	All user interaction with the dialog is	 communicated  to  the
       caller  via  the	 -command  callback and	the <<TkFontchooser*>> virtual
       events.	It is implementation dependent which exact user	actions	result
       in the callback being called resp. the virtual events being sent. Where
       an Apply	or OK button is	present	in the dialog, that button will	 trig-
       ger  the	 -command  callback  and  <<TkFontchooserFontChanged>> virtual
       event. On some implementations other user actions may  also  have  that
       effect;	on  Mac	 OS X for instance, the	standard font selection	dialog
       immediately reflects all	user choices to	the caller.

       In the presence of multiple widgets intended to be  influenced  by  the
       font selection dialog, care needs to be taken to	correctly handle focus
       changes:	the font selected in the dialog	should always match  the  cur-
       rent  font  of  the  widget  with  the focus, and the -command callback
       should only act on the widget with the focus. The recommended  practice
       is  to  set  font  dialog  -font	 and -command configuration options in
       per-widget <FocusIn> handlers (and if necessary to unset	 them  -  i.e.
       set  to	the empty string - in corresponding <FocusOut> handlers). This
       is particularly important for implementers of library  code  using  the
       font  selection dialog, to avoid	conflicting with application code that
       may also	want to	use the	dialog.

       Because the font	selection dialog is application-global,	in  the	 pres-
       ence of multiple	interpreters calling tk	fontchooser, only the -command
       callback	 set  by  the  interpreter  that  most	recently   called   tk
       fontchooser  configure  or  tk  fontchooser show	will be	invoked	in re-
       sponse to user action and only the -parent set by that interpreter will
       receive <<TkFontchooser*>> virtual events.

       The  font dialog	implementation may only	store (and return) font	actual
       data as the value of the	-font configuration option. This can be	an is-
       sue  when  -font	 is  set to a named font, if that font is subsequently
       changed,	the font dialog	-font option needs to be set again  to	ensure
       its selected font matches the new value of the named font.

EXAMPLE
	      proc fontchooserDemo {} {
		  wm title . "Font Chooser Demo"
		  tk fontchooser configure -parent .
		  button .b -command fontchooserToggle -takefocus 0
		  fontchooserVisibility	.b
		  bind . <<TkFontchooserVisibility>> \
			  [list	fontchooserVisibility .b]
		  foreach w {.t1 .t2} {
		      text $w -width 20	-height	4 -borderwidth 1 -relief solid
		      bind $w <FocusIn>	[list fontchooserFocus $w]
		      $w insert	end "Text Widget $w"
		  }
		  .t1 configure	-font {Courier 14}
		  .t2 configure	-font {Times 16}
		  pack .b .t1 .t2; focus .t1
	      }
	      proc fontchooserToggle {}	{
		  tk fontchooser [expr {
			  [tk fontchooser configure -visible] ?
			  "hide" : "show"}]
	      }
	      proc fontchooserVisibility {w} {
		  $w configure -text [expr {
			  [tk fontchooser configure -visible] ?
			  "Hide	Font Dialog" : "Show Font Dialog"}]
	      }
	      proc fontchooserFocus {w}	{
		  tk fontchooser configure -font [$w cget -font] \
			  -command [list fontchooserFontSelection $w]
	      }
	      proc fontchooserFontSelection {w font args} {
		  $w configure -font [font actual $font]
	      }
	      fontchooserDemo

SEE ALSO
       font(n),	tk(n)

KEYWORDS
       dialog, font, font selection, font chooser, font	panel

Tk								fontchooser(n)

NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION OPTIONS | VIRTUAL EVENTS | NOTES | EXAMPLE | SEE ALSO | KEYWORDS

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