man/man3/Tk_CanvasTextInfo.3 - toolchains/skids - Git at Google

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 '\" .OP cmdName dbName dbClass
 '\"	Start of description of a specific option.  cmdName gives the
 '\"	option's name as specified in the class command, dbName gives
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 '\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
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 See the \\fBoptions\\fR manual entry for details on the standard options.
 ..
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 Command-Line Name:	\\fB\\$1\\fR
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 .TH Tk_CanvasTextInfo 3 4.0 Tk "Tk Library Procedures"
 .BS
 .SH NAME
 Tk_CanvasTextInfo \- additional information for managing text items in canvases
 .SH SYNOPSIS
 .nf
 \fB#include <tk.h>\fR
 .sp
 Tk_CanvasTextInfo *
 \fBTk_CanvasGetTextInfo\fR(\fIcanvas\fR)
 .SH ARGUMENTS
 .AS Tk_Canvas canvas
 .AP Tk_Canvas canvas in
 A token that identifies a particular canvas widget.
 .BE

 .SH DESCRIPTION
 .PP
 Textual canvas items are somewhat more complicated to manage than
 other items, due to things like the selection and the input focus.
 \fBTk_CanvasGetTextInfo\fR may be invoked by a type manager
 to obtain additional information needed for items that display text.
 The return value from \fBTk_CanvasGetTextInfo\fR is a pointer to
 a structure that is shared between Tk and all the items that display
 text.
 The structure has the following form:
 .CS
 typedef struct Tk_CanvasTextInfo {
 	Tk_3DBorder \fIselBorder\fR;
 	int \fIselBorderWidth\fR;
 	XColor *\fIselFgColorPtr\fR;
 	Tk_Item *\fIselItemPtr\fR;
 	int \fIselectFirst\fR;
 	int \fIselectLast\fR;
 	Tk_Item *\fIanchorItemPtr\fR;
 	int \fIselectAnchor\fR;
 	Tk_3DBorder \fIinsertBorder\fR;
 	int \fIinsertWidth\fR;
 	int \fIinsertBorderWidth\fR;
 	Tk_Item *\fIfocusItemPtr\fR;
 	int \fIgotFocus\fR;
 	int \fIcursorOn\fR;
 } Tk_CanvasTextInfo;
 .CE
 The \fBselBorder\fR field identifies a Tk_3DBorder that should be
 used for drawing the background under selected text.
 \fIselBorderWidth\fR gives the width of the raised border around
 selected text, in pixels.
 \fIselFgColorPtr\fR points to an XColor that describes the foreground
 color to be used when drawing selected text.
 \fIselItemPtr\fR points to the item that is currently selected, or
 NULL if there is no item selected or if the canvas doesn't have the
 selection.
 \fIselectFirst\fR and \fIselectLast\fR give the indices of the first
 and last selected characters in \fIselItemPtr\fR, as returned by the
 \fIindexProc\fR for that item.
 \fIanchorItemPtr\fR points to the item that currently has the selection
 anchor;  this is not necessarily the same as \fIselItemPtr\fR.
 \fIselectAnchor\fR is an index that identifies the anchor position
 within \fIanchorItemPtr\fR.
 \fIinsertBorder\fR contains a Tk_3DBorder to use when drawing the
 insertion cursor;  \fIinsertWidth\fR gives the total width of the
 insertion cursor in pixels, and \fIinsertBorderWidth\fR gives the
 width of the raised  border around the insertion cursor.
 \fIfocusItemPtr\fR identifies the item that currently has the input
 focus, or NULL if there is no such item.
 \fIgotFocus\fR is 1 if the canvas widget has the input focus and
 0 otherwise.
 \fIcursorOn\fR is 1 if the insertion cursor should be drawn in
 \fIfocusItemPtr\fR and 0 if it should not be drawn;  this field
 is toggled on and off by Tk to make the cursor blink.
 .PP
 The structure returned by \fBTk_CanvasGetTextInfo\fR
 is shared between Tk and the type managers;  typically the type manager
 calls \fBTk_CanvasGetTextInfo\fR once when an item is created and
 then saves the pointer in the item's record.
 Tk will update information in the Tk_CanvasTextInfo;  for example,
 a \fBconfigure\fR widget command might change the \fIselBorder\fR
 field, or a \fBselect\fR widget command might change the \fIselectFirst\fR
 field, or Tk might change \fIcursorOn\fR in order to make the insertion
 cursor flash on and off during successive redisplays.
 .PP
 Type managers should treat all of the fields of the Tk_CanvasTextInfo
 structure as read-only, except for \fIselItemPtr\fR, \fIselectFirst\fR,
 \fIselectLast\fR, and \fIselectAnchor\fR.
 Type managers may change \fIselectFirst\fR, \fIselectLast\fR, and
 \fIselectAnchor\fR to adjust for insertions and deletions in the
 item (but only if the item is the current owner of the selection or
 anchor, as determined by \fIselItemPtr\fR or \fIanchorItemPtr\fR).
 If all of the selected text in the item is deleted, the item should
 set \fIselItemPtr\fR to NULL to indicate that there is no longer a
 selection.

 .SH KEYWORDS
 canvas, focus, insertion cursor, selection, selection anchor, text
	'\"
	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	'\"
	'\" See the file "license.terms" for information on usage and redistribution
	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	'\"
	'\" RCS: @(#) $Id: CanvTxtInfo.3,v 1.2 1998/09/14 18:22:46 stanton Exp $
	'\"
	'\" The definitions below are for supplemental macros used in Tcl/Tk
	'\" manual entries.
	'\"
	'\" .AP type name in/out ?indent?
	'\" Start paragraph describing an argument to a library procedure.
	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	'\" or "in/out" to describe whether procedure reads or modifies arg,
	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	'\" needed; use .AS below instead)
	'\"
	'\" .AS ?type? ?name?
	'\" Give maximum sizes of arguments for setting tab stops. Type and
	'\" name are examples of largest possible arguments that will be passed
	'\" to .AP later. If args are omitted, default tab stops are used.
	'\"
	'\" .BS
	'\" Start box enclosure. From here until next .BE, everything will be
	'\" enclosed in one large box.
	'\"
	'\" .BE
	'\" End of box enclosure.
	'\"
	'\" .CS
	'\" Begin code excerpt.
	'\"
	'\" .CE
	'\" End code excerpt.
	'\"
	'\" .VS ?version? ?br?
	'\" Begin vertical sidebar, for use in marking newly-changed parts
	'\" of man pages. The first argument is ignored and used for recording
	'\" the version when the .VS was added, so that the sidebars can be
	'\" found and removed when they reach a certain age. If another argument
	'\" is present, then a line break is forced before starting the sidebar.
	'\"
	'\" .VE
	'\" End of vertical sidebar.
	'\"
	'\" .DS
	'\" Begin an indented unfilled display.
	'\"
	'\" .DE
	'\" End of indented unfilled display.
	'\"
	'\" .SO
	'\" Start of list of standard options for a Tk widget. The
	'\" options follow on successive lines, in four columns separated
	'\" by tabs.
	'\"
	'\" .SE
	'\" End of list of standard options for a Tk widget.
	'\"
	'\" .OP cmdName dbName dbClass
	'\" Start of description of a specific option. cmdName gives the
	'\" option's name as specified in the class command, dbName gives
	'\" the option's name in the option database, and dbClass gives
	'\" the option's class in the option database.
	'\"
	'\" .UL arg1 arg2
	'\" Print arg1 underlined, then print arg2 normally.
	'\"
	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
	'\"
	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
	.if t .wh -1.3i ^B
	.nr ^l \n(.l
	.ad b
	'\" # Start an argument description
	.de AP
	.ie !"\\$4"" .TP \\$4
	.el \{\
	. ie !"\\$2"" .TP \\n()Cu
	. el .TP 15
	.\}
	.ta \\n()Au \\n()Bu
	.ie !"\\$3"" \{\
	\&\\$1 \\fI\\$2\\fP (\\$3)
	.\".b
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	..
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	.if !"\\$1"" .nr )A \\w'\\$1'u+3n
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	.\"
	.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
	.nr )C \\n()Bu+\\w'(in/out)'u+2n
	..
	.AS Tcl_Interp Tcl_CreateInterp in/out
	'\" # BS - start boxed text
	'\" # ^y = starting y location
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	..
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	.el \{\
	.\" Draw four-sided box normally, but don't draw top of
	.\" box if the box started on an earlier page.
	.ie !\\n(^b-1 \{\
	\h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
	.\}
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	\h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
	.\}
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	.sp -1
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	.\}
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	'\" # box/sidebar if in box/sidebar mode, then invoked standard
	'\" # page bottom macro.
	.de ^B
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	'ti 0
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	.mk ^t
	.if \\n(^b \{\
	.\" Draw three-sided box if this is the box's first page,
	.\" draw two sides but no top otherwise.
	.ie !\\n(^b-1 \h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
	.\}
	.if \\n(^v \{\
	.nr ^x \\n(^tu+1v-\\n(^Yu
	\kx\h'-\\nxu'\h'\|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'\|0u'\c
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	..
	'\" # SO - start of list of standard options
	.de SO
	.SH "STANDARD OPTIONS"
	.LP
	.nf
	.ta 5.5c 11c
	.ft B
	..
	'\" # SE - end of list of standard options
	.de SE
	.fi
	.ft R
	.LP
	See the \\fBoptions\\fR manual entry for details on the standard options.
	..
	'\" # OP - start of full description for a single option
	.de OP
	.LP
	.nf
	.ta 4c
	Command-Line Name: \\fB\\$1\\fR
	Database Name: \\fB\\$2\\fR
	Database Class: \\fB\\$3\\fR
	.fi
	.IP
	..
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	..
	.de UL
	\\$1\l'\|0\(ul'\\$2
	..
	.TH Tk_CanvasTextInfo 3 4.0 Tk "Tk Library Procedures"
	.BS
	.SH NAME
	Tk_CanvasTextInfo \- additional information for managing text items in canvases
	.SH SYNOPSIS
	.nf
	\fB#include <tk.h>\fR
	.sp
	Tk_CanvasTextInfo *
	\fBTk_CanvasGetTextInfo\fR(\fIcanvas\fR)
	.SH ARGUMENTS
	.AS Tk_Canvas canvas
	.AP Tk_Canvas canvas in
	A token that identifies a particular canvas widget.
	.BE

	.SH DESCRIPTION
	.PP
	Textual canvas items are somewhat more complicated to manage than
	other items, due to things like the selection and the input focus.
	\fBTk_CanvasGetTextInfo\fR may be invoked by a type manager
	to obtain additional information needed for items that display text.
	The return value from \fBTk_CanvasGetTextInfo\fR is a pointer to
	a structure that is shared between Tk and all the items that display
	text.
	The structure has the following form:
	.CS
	typedef struct Tk_CanvasTextInfo {
	Tk_3DBorder \fIselBorder\fR;
	int \fIselBorderWidth\fR;
	XColor *\fIselFgColorPtr\fR;
	Tk_Item *\fIselItemPtr\fR;
	int \fIselectFirst\fR;
	int \fIselectLast\fR;
	Tk_Item *\fIanchorItemPtr\fR;
	int \fIselectAnchor\fR;
	Tk_3DBorder \fIinsertBorder\fR;
	int \fIinsertWidth\fR;
	int \fIinsertBorderWidth\fR;
	Tk_Item *\fIfocusItemPtr\fR;
	int \fIgotFocus\fR;
	int \fIcursorOn\fR;
	} Tk_CanvasTextInfo;
	.CE
	The \fBselBorder\fR field identifies a Tk_3DBorder that should be
	used for drawing the background under selected text.
	\fIselBorderWidth\fR gives the width of the raised border around
	selected text, in pixels.
	\fIselFgColorPtr\fR points to an XColor that describes the foreground
	color to be used when drawing selected text.
	\fIselItemPtr\fR points to the item that is currently selected, or
	NULL if there is no item selected or if the canvas doesn't have the
	selection.
	\fIselectFirst\fR and \fIselectLast\fR give the indices of the first
	and last selected characters in \fIselItemPtr\fR, as returned by the
	\fIindexProc\fR for that item.
	\fIanchorItemPtr\fR points to the item that currently has the selection
	anchor; this is not necessarily the same as \fIselItemPtr\fR.
	\fIselectAnchor\fR is an index that identifies the anchor position
	within \fIanchorItemPtr\fR.
	\fIinsertBorder\fR contains a Tk_3DBorder to use when drawing the
	insertion cursor; \fIinsertWidth\fR gives the total width of the
	insertion cursor in pixels, and \fIinsertBorderWidth\fR gives the
	width of the raised border around the insertion cursor.
	\fIfocusItemPtr\fR identifies the item that currently has the input
	focus, or NULL if there is no such item.
	\fIgotFocus\fR is 1 if the canvas widget has the input focus and
	0 otherwise.
	\fIcursorOn\fR is 1 if the insertion cursor should be drawn in
	\fIfocusItemPtr\fR and 0 if it should not be drawn; this field
	is toggled on and off by Tk to make the cursor blink.
	.PP
	The structure returned by \fBTk_CanvasGetTextInfo\fR
	is shared between Tk and the type managers; typically the type manager
	calls \fBTk_CanvasGetTextInfo\fR once when an item is created and
	then saves the pointer in the item's record.
	Tk will update information in the Tk_CanvasTextInfo; for example,
	a \fBconfigure\fR widget command might change the \fIselBorder\fR
	field, or a \fBselect\fR widget command might change the \fIselectFirst\fR
	field, or Tk might change \fIcursorOn\fR in order to make the insertion
	cursor flash on and off during successive redisplays.
	.PP
	Type managers should treat all of the fields of the Tk_CanvasTextInfo
	structure as read-only, except for \fIselItemPtr\fR, \fIselectFirst\fR,
	\fIselectLast\fR, and \fIselectAnchor\fR.
	Type managers may change \fIselectFirst\fR, \fIselectLast\fR, and
	\fIselectAnchor\fR to adjust for insertions and deletions in the
	item (but only if the item is the current owner of the selection or
	anchor, as determined by \fIselItemPtr\fR or \fIanchorItemPtr\fR).
	If all of the selected text in the item is deleted, the item should
	set \fIselItemPtr\fR to NULL to indicate that there is no longer a
	selection.

	.SH KEYWORDS
	canvas, focus, insertion cursor, selection, selection anchor, text