[OpenSPARC-T2-SAM] / sam-t2 / devtools / v8plus / man / man3 / Tk_CanvasTextInfo.3

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'\" The definitions below are for supplemental macros used in Tcl/Tk
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'\" .OP cmdName dbName dbClass
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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
Commit	Line	Data
920dae64 AT	1	'\"
	2	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	3	'\"
	4	'\" See the file "license.terms" for information on usage and redistribution
	5	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	6	'\"
	7	'\" RCS: @(#) $Id: CanvTxtInfo.3,v 1.2 1998/09/14 18:22:46 stanton Exp $
	8	'\"
	9	'\" The definitions below are for supplemental macros used in Tcl/Tk
	10	'\" manual entries.
	11	'\"
	12	'\" .AP type name in/out ?indent?
	13	'\" Start paragraph describing an argument to a library procedure.
	14	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	15	'\" or "in/out" to describe whether procedure reads or modifies arg,
	16	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	17	'\" needed; use .AS below instead)
	18	'\"
	19	'\" .AS ?type? ?name?
	20	'\" Give maximum sizes of arguments for setting tab stops. Type and
	21	'\" name are examples of largest possible arguments that will be passed
	22	'\" to .AP later. If args are omitted, default tab stops are used.
	23	'\"
	24	'\" .BS
	25	'\" Start box enclosure. From here until next .BE, everything will be
	26	'\" enclosed in one large box.
	27	'\"
	28	'\" .BE
	29	'\" End of box enclosure.
	30	'\"
	31	'\" .CS
	32	'\" Begin code excerpt.
	33	'\"
	34	'\" .CE
	35	'\" End code excerpt.
	36	'\"
	37	'\" .VS ?version? ?br?
	38	'\" Begin vertical sidebar, for use in marking newly-changed parts
	39	'\" of man pages. The first argument is ignored and used for recording
	40	'\" the version when the .VS was added, so that the sidebars can be
	41	'\" found and removed when they reach a certain age. If another argument
	42	'\" is present, then a line break is forced before starting the sidebar.
	43	'\"
	44	'\" .VE
	45	'\" End of vertical sidebar.
	46	'\"
	47	'\" .DS
	48	'\" Begin an indented unfilled display.
	49	'\"
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	51	'\" End of indented unfilled display.
	52	'\"
	53	'\" .SO
	54	'\" Start of list of standard options for a Tk widget. The
	55	'\" options follow on successive lines, in four columns separated
	56	'\" by tabs.
	57	'\"
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	59	'\" End of list of standard options for a Tk widget.
	60	'\"
	61	'\" .OP cmdName dbName dbClass
	62	'\" Start of description of a specific option. cmdName gives the
	63	'\" option's name as specified in the class command, dbName gives
	64	'\" the option's name in the option database, and dbClass gives
65	'\" the option's class in the option database.
66	'\"
67	'\" .UL arg1 arg2
68	'\" Print arg1 underlined, then print arg2 normally.
69	'\"
70	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
71	'\"
72	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
73	.if t .wh -1.3i ^B
74	.nr ^l \n(.l
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78	.ie !"\\$4"" .TP \\$4
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80	. ie !"\\$2"" .TP \\n()Cu
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107	.AS Tcl_Interp Tcl_CreateInterp in/out
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176	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
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206	.de SO
207	.SH "STANDARD OPTIONS"
208	.LP
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212	..
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218	See the \\fBoptions\\fR manual entry for details on the standard options.
219	..
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243	\\$1\l'\|0\(ul'\\$2
244	..
245	.TH Tk_CanvasTextInfo 3 4.0 Tk "Tk Library Procedures"
246	.BS
247	.SH NAME
248	Tk_CanvasTextInfo \- additional information for managing text items in canvases
249	.SH SYNOPSIS
250	.nf
251	\fB#include <tk.h>\fR
252	.sp
253	Tk_CanvasTextInfo *
254	\fBTk_CanvasGetTextInfo\fR(\fIcanvas\fR)
255	.SH ARGUMENTS
256	.AS Tk_Canvas canvas
257	.AP Tk_Canvas canvas in
258	A token that identifies a particular canvas widget.
259	.BE
260
261	.SH DESCRIPTION
262	.PP
263	Textual canvas items are somewhat more complicated to manage than
264	other items, due to things like the selection and the input focus.
265	\fBTk_CanvasGetTextInfo\fR may be invoked by a type manager
266	to obtain additional information needed for items that display text.
267	The return value from \fBTk_CanvasGetTextInfo\fR is a pointer to
268	a structure that is shared between Tk and all the items that display
269	text.
270	The structure has the following form:
271	.CS
272	typedef struct Tk_CanvasTextInfo {
273	Tk_3DBorder \fIselBorder\fR;
274	int \fIselBorderWidth\fR;
275	XColor *\fIselFgColorPtr\fR;
276	Tk_Item *\fIselItemPtr\fR;
277	int \fIselectFirst\fR;
278	int \fIselectLast\fR;
279	Tk_Item *\fIanchorItemPtr\fR;
280	int \fIselectAnchor\fR;
281	Tk_3DBorder \fIinsertBorder\fR;
282	int \fIinsertWidth\fR;
283	int \fIinsertBorderWidth\fR;
284	Tk_Item *\fIfocusItemPtr\fR;
285	int \fIgotFocus\fR;
286	int \fIcursorOn\fR;
287	} Tk_CanvasTextInfo;
288	.CE
289	The \fBselBorder\fR field identifies a Tk_3DBorder that should be
290	used for drawing the background under selected text.
291	\fIselBorderWidth\fR gives the width of the raised border around
292	selected text, in pixels.
293	\fIselFgColorPtr\fR points to an XColor that describes the foreground
294	color to be used when drawing selected text.
295	\fIselItemPtr\fR points to the item that is currently selected, or
296	NULL if there is no item selected or if the canvas doesn't have the
297	selection.
298	\fIselectFirst\fR and \fIselectLast\fR give the indices of the first
299	and last selected characters in \fIselItemPtr\fR, as returned by the
300	\fIindexProc\fR for that item.
301	\fIanchorItemPtr\fR points to the item that currently has the selection
302	anchor; this is not necessarily the same as \fIselItemPtr\fR.
303	\fIselectAnchor\fR is an index that identifies the anchor position
304	within \fIanchorItemPtr\fR.
305	\fIinsertBorder\fR contains a Tk_3DBorder to use when drawing the
306	insertion cursor; \fIinsertWidth\fR gives the total width of the
307	insertion cursor in pixels, and \fIinsertBorderWidth\fR gives the
308	width of the raised border around the insertion cursor.
309	\fIfocusItemPtr\fR identifies the item that currently has the input
310	focus, or NULL if there is no such item.
311	\fIgotFocus\fR is 1 if the canvas widget has the input focus and
312	0 otherwise.
313	\fIcursorOn\fR is 1 if the insertion cursor should be drawn in
314	\fIfocusItemPtr\fR and 0 if it should not be drawn; this field
315	is toggled on and off by Tk to make the cursor blink.
316	.PP
317	The structure returned by \fBTk_CanvasGetTextInfo\fR
318	is shared between Tk and the type managers; typically the type manager
319	calls \fBTk_CanvasGetTextInfo\fR once when an item is created and
320	then saves the pointer in the item's record.
321	Tk will update information in the Tk_CanvasTextInfo; for example,
322	a \fBconfigure\fR widget command might change the \fIselBorder\fR
323	field, or a \fBselect\fR widget command might change the \fIselectFirst\fR
324	field, or Tk might change \fIcursorOn\fR in order to make the insertion
325	cursor flash on and off during successive redisplays.
326	.PP
327	Type managers should treat all of the fields of the Tk_CanvasTextInfo
328	structure as read-only, except for \fIselItemPtr\fR, \fIselectFirst\fR,
329	\fIselectLast\fR, and \fIselectAnchor\fR.
330	Type managers may change \fIselectFirst\fR, \fIselectLast\fR, and
331	\fIselectAnchor\fR to adjust for insertions and deletions in the
332	item (but only if the item is the current owner of the selection or
333	anchor, as determined by \fIselItemPtr\fR or \fIanchorItemPtr\fR).
334	If all of the selected text in the item is deleted, the item should
335	set \fIselItemPtr\fR to NULL to indicate that there is no longer a
336	selection.
337
338	.SH KEYWORDS
339	canvas, focus, insertion cursor, selection, selection anchor, text