text(n) manual page
Table of Contents
text, tk_textCopy, tk_textCut, tk_textPaste
- Create and manipulate text widgets
text pathName ?options?
tk_textCopy pathName
tk_textCut pathName
tk_textPaste pathName
STANDARD OPTIONS-background-highlightthickness-relief-borderwidth-insertbackground-selectbackground-cursor-insertborderwidth-selectborderwidth-exportselection-insertofftime-selectforeground-font-insertontime-setgrid-foreground-insertwidth-takefocus-highlightbackground-padx-xscrollcommand-highlightcolor-pady-yscrollcommand
Widget-specific
OptionsCommand-Line Name: -autoseparators
Database Name: autoSeparators
Database Class: AutoSeparators
Specifies a boolean that says whether separators are automatically inserted
in the undo stack. Only meaningful when the -undo option is true. Command-Line
Name: -height
Database Name: height
Database Class: Height
Specifies the desired height for the window, in units of characters in
the font given by the -font option. Must be at least one. Command-Line Name:
-maxundo
Database Name: maxUndo
Database Class: MaxUndo
Specifies the maximum number of compound undo actions on the undo stack.
A zero or a negative value imply an unlimited undo stack. Command-Line Name:
-spacing1
Database Name: spacing1
Database Class: Spacing1
Requests additional space above each text line in the widget, using any
of the standard forms for screen distances. If a line wraps, this option
only applies to the first line on the display. This option may be overridden
with -spacing1 options in tags. Command-Line Name: -spacing2
Database Name: spacing2
Database Class: Spacing2
For lines that wrap (so that they cover more than one line on the display)
this option specifies additional space to provide between the display lines
that represent a single line of text. The value may have any of the standard
forms for screen distances. This option may be overridden with -spacing2
options in tags. Command-Line Name: -spacing3
Database Name: spacing3
Database Class: Spacing3
Requests additional space below each text line in the widget, using any
of the standard forms for screen distances. If a line wraps, this option
only applies to the last line on the display. This option may be overridden
with -spacing3 options in tags. Command-Line Name: -state
Database Name: state
Database Class: State
Specifies one of two states for the text: normal or disabled. If the text
is disabled then characters may not be inserted or deleted and no insertion
cursor will be displayed, even if the input focus is in the widget. Command-Line
Name: -tabs
Database Name: tabs
Database Class: Tabs
Specifies a set of tab stops for the window. The option’s value consists
of a list of screen distances giving the positions of the tab stops, each
of which is a distance relative to the left edge of the widget (excluding
borders, padding, etc). Each position may optionally be followed in the
next list element by one of the keywords left, right, center, or numeric,
which specifies how to justify text relative to the tab stop. Left is the
default; it causes the text following the tab character to be positioned
with its left edge at the tab position. Right means that the right edge
of the text following the tab character is positioned at the tab position,
and center means that the text is centered at the tab position. Numeric
means that the decimal point in the text is positioned at the tab position;
if there is no decimal point then the least significant digit of the number
is positioned just to the left of the tab position; if there is no number
in the text then the text is right-justified at the tab position. For example,
-tabs {2c left 4c 6c center} creates three tab stops at two-centimeter intervals;
the first two use left justification and the third uses center justification.
If the list of tab stops does not have enough elements to cover all of
the tabs in a text line, then Tk extrapolates new tab stops using the spacing
and alignment from the last tab stop in the list. Tab distances must be
strictly positive, and must always increase from one tab stop to the next
(if not, an error is thrown). The value of the tabs option may be overridden
by -tabs options in tags. If no -tabs option is specified, or if it is specified
as an empty list, then Tk uses default tabs spaced every eight (average
size) characters. Command-Line Name: -undo
Database Name: undo
Database Class: Undo
Specifies a boolean that says whether the undo mechanism is active or not.
Command-Line Name: -width
Database Name: width
Database Class: Width
Specifies the desired width for the window in units of characters in the
font given by the -font option. If the font doesn’t have a uniform width then
the width of the character ‘‘0’’ is used in translating from character units
to screen units. Command-Line Name: -wrap
Database Name: wrap
Database Class: Wrap
Specifies how to handle lines in the text that are too long to be displayed
in a single line of the text’s window. The value must be none or char or
word. A wrap mode of none means that each line of text appears as exactly
one line on the screen; extra characters that don’t fit on the screen are
not displayed. In the other modes each line of text will be broken up into
several screen lines if necessary to keep all the characters visible. In
char mode a screen line break may occur after any character; in word mode
a line break will only be made at word boundaries. DescriptionThe text
command creates a new window (given by the pathName argument) and makes
it into a text widget. Additional options, described above, may be specified
on the command line or in the option database to configure aspects of the
text such as its default background color and relief. The text command
returns the path name of the new window.
A text widget displays one or more
lines of text and allows that text to be edited. Text widgets support four
different kinds of annotations on the text, called tags, marks, embedded
windows or embedded images. Tags allow different portions of the text to
be displayed with different fonts and colors. In addition, Tcl commands
can be associated with tags so that scripts are invoked when particular
actions such as keystrokes and mouse button presses occur in particular
ranges of the text. See TAGS below for more details.
The second form of annotation
consists of floating markers in the text called "marks". Marks are used
to keep track of various interesting positions in the text as it is edited.
See MARKS below for more details.
The third form of annotation allows arbitrary
windows to be embedded in a text widget. See EMBEDDED WINDOWS below for
more details.
The fourth form of annotation allows Tk images to be embedded
in a text widget. See EMBEDDED IMAGES below for more details.
The text widget
also has a built-in undo/redo mechanism. See THE UNDO MECHANISM below for
more details.
IndicesMany of the widget commands for texts take one or more
indices as arguments. An index is a string used to indicate a particular
place within a text, such as a place to insert characters or one endpoint
of a range of characters to delete. Indices have the syntax
base modifier modifier modifier ...
Where base gives a starting point and the modifiers adjust the index from
the starting point (e.g. move forward or backward one character). Every index
must contain a base, but the modifiers are optional.
The base for an index
must have one of the following forms:
line.char Indicates char’th character
on line line. Lines are numbered from 1 for consistency with other UNIX
programs that use this numbering scheme. Within a line, characters are numbered
from 0. If char is end then it refers to the newline character that ends
the line. @x,y Indicates the character that covers the pixel whose x and
y coordinates within the text’s window are x and y. end Indicates the end
of the text (the character just after the last newline). mark Indicates
the character just after the mark whose name is mark. tag.first Indicates
the first character in the text that has been tagged with tag. This form
generates an error if no characters are currently tagged with tag. tag.last
Indicates the character just after the last one in the text that has been
tagged with tag. This form generates an error if no characters are currently
tagged with tag. pathName Indicates the position of the embedded window
whose name is pathName. This form generates an error if there is no embedded
window by the given name. imageName Indicates the position of the embedded
image whose name is imageName. This form generates an error if there is
no embedded image by the given name. If the base could match more than one
of the above forms, such as a mark and imageName both having the same value,
then the form earlier in the above list takes precedence. If modifiers follow
the base index, each one of them must have one of the forms listed below.
Keywords such as chars and wordend may be abbreviated as long as the abbreviation
is unambiguous.
+ count chars Adjust the index forward by count characters,
moving to later lines in the text if necessary. If there are fewer than
count characters in the text after the current index, then set the index
to the last character in the text. Spaces on either side of count are optional.
- count chars Adjust the index backward by count characters, moving to earlier
lines in the text if necessary. If there are fewer than count characters
in the text before the current index, then set the index to the first character
in the text. Spaces on either side of count are optional. + count lines Adjust
the index forward by count lines, retaining the same character position
within the line. If there are fewer than count lines after the line containing
the current index, then set the index to refer to the same character position
on the last line of the text. Then, if the line is not long enough to contain
a character at the indicated character position, adjust the character position
to refer to the last character of the line (the newline). Spaces on either
side of count are optional. - count lines Adjust the index backward by count
lines, retaining the same character position within the line. If there
are fewer than count lines before the line containing the current index,
then set the index to refer to the same character position on the first
line of the text. Then, if the line is not long enough to contain a character
at the indicated character position, adjust the character position to refer
to the last character of the line (the newline). Spaces on either side of
count are optional. linestart Adjust the index to refer to the first character
on the line. lineend Adjust the index to refer to the last character on
the line (the newline). wordstart Adjust the index to refer to the first
character of the word containing the current index. A word consists of
any number of adjacent characters that are letters, digits, or underscores,
or a single character that is not one of these. wordend Adjust the index
to refer to the character just after the last one of the word containing
the current index. If the current index refers to the last character of
the text then it is not modified. If more than one modifier is present then
they are applied in left-to-right order. For example, the index ‘‘end - 1 chars’’
refers to the next-to-last character in the text and ‘‘insert wordstart - 1
c’’ refers to the character just before the first one in the word containing
the insertion cursor. Modifiers are applied one by one in this left to
right order, and after each step the resulting index is constrained to
be a valid index in the text widget. So, for example, the index ‘‘1.0 -1c
+1c’’ refers to the index ‘‘2.0’’.
TagsThe first form of annotation in text widgets
is a tag. A tag is a textual string that is associated with some of the
characters in a text. Tags may contain arbitrary characters, but it is probably
best to avoid using the characters ‘‘ ’’ (space), +, or -: these characters
have special meaning in indices, so tags containing them can’t be used as
indices. There may be any number of tags associated with characters in a
text. Each tag may refer to a single character, a range of characters, or
several ranges of characters. An individual character may have any number
of tags associated with it.
A priority order is defined among tags, and
this order is used in implementing some of the tag-related functions described
below. When a tag is defined (by associating it with characters or setting
its display options or binding commands to it), it is given a priority
higher than any existing tag. The priority order of tags may be redefined
using the ‘‘pathName tag raise’’ and ‘‘pathName tag lower’’ widget commands.
Tags
serve three purposes in text widgets. First, they control the way information
is displayed on the screen. By default, characters are displayed as determined
by the background, font, and foreground options for the text widget. However,
display options may be associated with individual tags using the ‘‘pathName
tag configure’’ widget command. If a character has been tagged, then the display
options associated with the tag override the default display style. The
following options are currently supported for tags:
-background color Color
specifies the background color to use for characters associated with the
tag. It may have any of the forms accepted by Tk_GetColor. -bgstipple bitmap
Bitmap specifies a bitmap that is used as a stipple pattern for the background.
It may have any of the forms accepted by Tk_GetBitmap. If bitmap hasn’t been
specified, or if it is specified as an empty string, then a solid fill
will be used for the background. -borderwidth pixels Pixels specifies the
width of a 3-D border to draw around the background. It may have any of the
forms accepted by Tk_GetPixels. This option is used in conjunction with
the -relief option to give a 3-D appearance to the background for characters;
it is ignored unless the -background option has been set for the tag. -elide
boolean Elide specifies whether the data should be elided. Elided data is
not displayed and takes no space on screen, but further on behaves just
as normal data. -fgstipple bitmap Bitmap specifies a bitmap that is used
as a stipple pattern when drawing text and other foreground information
such as underlines. It may have any of the forms accepted by Tk_GetBitmap.
If bitmap hasn’t been specified, or if it is specified as an empty string,
then a solid fill will be used. -font fontName FontName is the name of a
font to use for drawing characters. It may have any of the forms accepted
by Tk_GetFont. -foreground color Color specifies the color to use when drawing
text and other foreground information such as underlines. It may have any
of the forms accepted by Tk_GetColor. -justify justify If the first character
of a display line has a tag for which this option has been specified, then
justify determines how to justify the line. It must be one of left, right,
or center. If a line wraps, then the justification for each line on the
display is determined by the first character of that display line. -lmargin1
pixels If the first character of a text line has a tag for which this option
has been specified, then pixels specifies how much the line should be indented
from the left edge of the window. Pixels may have any of the standard forms
for screen distances. If a line of text wraps, this option only applies
to the first line on the display; the -lmargin2 option controls the indentation
for subsequent lines. -lmargin2 pixels If the first character of a display
line has a tag for which this option has been specified, and if the display
line is not the first for its text line (i.e., the text line has wrapped),
then pixels specifies how much the line should be indented from the left
edge of the window. Pixels may have any of the standard forms for screen
distances. This option is only used when wrapping is enabled, and it only
applies to the second and later display lines for a text line. -offset pixels
Pixels specifies an amount by which the text’s baseline should be offset
vertically from the baseline of the overall line, in pixels. For example,
a positive offset can be used for superscripts and a negative offset can
be used for subscripts. Pixels may have any of the standard forms for screen
distances. -overstrike boolean Specifies whether or not to draw a horizontal
rule through the middle of characters. Boolean may have any of the forms
accepted by Tcl_GetBoolean. -relief relief Relief specifies the 3-D relief
to use for drawing backgrounds, in any of the forms accepted by Tk_GetRelief.
This option is used in conjunction with the -borderwidth option to give
a 3-D appearance to the background for characters; it is ignored unless
the -background option has been set for the tag. -rmargin pixels If the first
character of a display line has a tag for which this option has been specified,
then pixels specifies how wide a margin to leave between the end of the
line and the right edge of the window. Pixels may have any of the standard
forms for screen distances. This option is only used when wrapping is enabled.
If a text line wraps, the right margin for each line on the display is
determined by the first character of that display line. -spacing1 pixels
Pixels specifies how much additional space should be left above each text
line, using any of the standard forms for screen distances. If a line wraps,
this option only applies to the first line on the display. -spacing2 pixels
For lines that wrap, this option specifies how much additional space to
leave between the display lines for a single text line. Pixels may have
any of the standard forms for screen distances. -spacing3 pixels Pixels specifies
how much additional space should be left below each text line, using any
of the standard forms for screen distances. If a line wraps, this option
only applies to the last line on the display. -tabs tabList TabList specifies
a set of tab stops in the same form as for the -tabs option for the text
widget. This option only applies to a display line if it applies to the
first character on that display line. If this option is specified as an
empty string, it cancels the option, leaving it unspecified for the tag
(the default). If the option is specified as a non-empty string that is an
empty list, such as -tags { }, then it requests default 8-character tabs
as described for the tags widget option. -underline boolean Boolean specifies
whether or not to draw an underline underneath characters. It may have any
of the forms accepted by Tcl_GetBoolean. -wrap mode Mode specifies how to
handle lines that are wider than the text’s window. It has the same legal
values as the -wrap option for the text widget: none, char, or word. If
this tag option is specified, it overrides the -wrap option for the text
widget. If a character has several tags associated with it, and if their
display options conflict, then the options of the highest priority tag
are used. If a particular display option hasn’t been specified for a particular
tag, or if it is specified as an empty string, then that option will never
be used; the next-highest-priority tag’s option will used instead. If no tag
specifies a particular display option, then the default style for the widget
will be used.
The second purpose for tags is event bindings. You can associate
bindings with a tag in much the same way you can associate bindings with
a widget class: whenever particular X events occur on characters with
the given tag, a given Tcl command will be executed. Tag bindings can be
used to give behaviors to ranges of characters; among other things, this
allows hypertext-like features to be implemented. For details, see the description
of the tag bind widget command below.
The third use for tags is in managing
the selection. See THE SELECTION below.
MarksThe second form of annotation
in text widgets is a mark. Marks are used for remembering particular places
in a text. They are something like tags, in that they have names and they
refer to places in the file, but a mark isn’t associated with particular
characters. Instead, a mark is associated with the gap between two characters.
Only a single position may be associated with a mark at any given time.
If the characters around a mark are deleted the mark will still remain;
it will just have new neighbor characters. In contrast, if the characters
containing a tag are deleted then the tag will no longer have an association
with characters in the file. Marks may be manipulated with the ‘‘pathName
mark’’ widget command, and their current locations may be determined by using
the mark name as an index in widget commands.
Each mark also has a "gravity",
which is either left or right. The gravity for a mark specifies what happens
to the mark when text is inserted at the point of the mark. If a mark has
left gravity, then the mark is treated as if it were attached to the character
on its left, so the mark will remain to the left of any text inserted at
the mark position. If the mark has right gravity, new text inserted at the
mark position will appear to the left of the mark (so that the mark remains
rightmost). The gravity for a mark defaults to right.
The name space for
marks is different from that for tags: the same name may be used for both
a mark and a tag, but they will refer to different things.
Two marks have
special significance. First, the mark insert is associated with the insertion
cursor, as described under THE INSERTION CURSOR below. Second, the mark
current is associated with the character closest to the mouse and is adjusted
automatically to track the mouse position and any changes to the text in
the widget (one exception: current is not updated in response to mouse
motions if a mouse button is down; the update will be deferred until all
mouse buttons have been released). Neither of these special marks may be
deleted.
Embedded WindowsThe third form of annotation in text widgets is
an embedded window. Each embedded window annotation causes a window to be
displayed at a particular point in the text. There may be any number of
embedded windows in a text widget, and any widget may be used as an embedded
window (subject to the usual rules for geometry management, which require
the text window to be the parent of the embedded window or a descendant
of its parent). The embedded window’s position on the screen will be updated
as the text is modified or scrolled, and it will be mapped and unmapped
as it moves into and out of the visible area of the text widget. Each embedded
window occupies one character’s worth of index space in the text widget,
and it may be referred to either by the name of its embedded window or
by its position in the widget’s index space. If the range of text containing
the embedded window is deleted then the window is destroyed.
When an embedded
window is added to a text widget with the window create widget command,
several configuration options may be associated with it. These options may
be modified later with the window configure widget command. The following
options are currently supported:
-align where If the window is not as tall
as the line in which it is displayed, this option determines where the
window is displayed in the line. Where must have one of the values top (align
the top of the window with the top of the line), center (center the window
within the range of the line), bottom (align the bottom of the window with
the bottom of the line’s area), or baseline (align the bottom of the window
with the baseline of the line). -create script Specifies a Tcl script that
may be evaluated to create the window for the annotation. If no -window option
has been specified for the annotation this script will be evaluated when
the annotation is about to be displayed on the screen. Script must create
a window for the annotation and return the name of that window as its result.
If the annotation’s window should ever be deleted, script will be evaluated
again the next time the annotation is displayed. -padx pixels Pixels specifies
the amount of extra space to leave on each side of the embedded window.
It may have any of the usual forms defined for a screen distance. -pady pixels
Pixels specifies the amount of extra space to leave on the top and on the
bottom of the embedded window. It may have any of the usual forms defined
for a screen distance. -stretch boolean If the requested height of the embedded
window is less than the height of the line in which it is displayed, this
option can be used to specify whether the window should be stretched vertically
to fill its line. If the -pady option has been specified as well, then the
requested padding will be retained even if the window is stretched. -window
pathName Specifies the name of a window to display in the annotation. Embedded
ImagesThe final form of annotation in text widgets is an embedded image.
Each embedded image annotation causes an image to be displayed at a particular
point in the text. There may be any number of embedded images in a text
widget, and a particular image may be embedded in multiple places in the
same text widget. The embedded image’s position on the screen will be updated
as the text is modified or scrolled. Each embedded image occupies one character’s
worth of index space in the text widget, and it may be referred to either
by its position in the widget’s index space, or the name it is assigned
when the image is inserted into the text widget with image create. If the
range of text containing the embedded image is deleted then that copy of
the image is removed from the screen.
When an embedded image is added to
a text widget with the image create widget command, a name unique to this
instance of the image is returned. This name may then be used to refer
to this image instance. The name is taken to be the value of the -name option
(described below). If the -name option is not provided, the -image name is
used instead. If the imageName is already in use in the text widget, then
#nn is added to the end of the imageName, where nn is an arbitrary integer.
This insures the imageName is unique. Once this name is assigned to this
instance of the image, it does not change, even though the -image or -name
values can be changed with image configure.
When an embedded image is added
to a text widget with the image create widget command, several configuration
options may be associated with it. These options may be modified later with
the image configure widget command. The following options are currently
supported:
-align where If the image is not as tall as the line in which
it is displayed, this option determines where the image is displayed in
the line. Where must have one of the values top (align the top of the image
with the top of the line), center (center the image within the range of
the line), bottom (align the bottom of the image with the bottom of the
line’s area), or baseline (align the bottom of the image with the baseline
of the line). -image image Specifies the name of the Tk image to display
in the annotation. If image is not a valid Tk image, then an error is returned.
-name ImageName Specifies the name by which this image instance may be referenced
in the text widget. If ImageName is not supplied, then the name of the Tk
image is used instead. If the imageName is already in use, #nn is appended
to the end of the name as described above. -padx pixels Pixels specifies
the amount of extra space to leave on each side of the embedded image. It
may have any of the usual forms defined for a screen distance. -pady pixels
Pixels specifies the amount of extra space to leave on the top and on the
bottom of the embedded image. It may have any of the usual forms defined
for a screen distance. the SelectionSelection support is implemented via
tags. If the exportSelection option for the text widget is true then the
sel tag will be associated with the selection:
[1]Whenever characters are
tagged with sel the text widget will claim ownership of the selection. [2]Attempts
to retrieve the selection will be serviced by the text widget, returning
all the characters with the sel tag. [3]If the selection is claimed away
by another application or by another window within this application, then
the sel tag will be removed from all characters in the text. [4]Whenever
the sel tag range changes a virtual event <<Selection>> is generated. The sel
tag is automatically defined when a text widget is created, and it may
not be deleted with the ‘‘pathName tag delete’’ widget command. Furthermore,
the selectBackground, selectBorderWidth, and selectForeground options for
the text widget are tied to the -background, -borderwidth, and -foreground
options for the sel tag: changes in either will automatically be reflected
in the other.
the Insertion CursorThe mark named insert has special significance
in text widgets. It is defined automatically when a text widget is created
and it may not be unset with the ‘‘pathName mark unset’’ widget command. The
insert mark represents the position of the insertion cursor, and the insertion
cursor will automatically be drawn at this point whenever the text widget
has the input focus.
the Modified FlagThe text widget can keep track of
changes to the content of the widget by means of the modified flag. Inserting
or deleting text will set this flag. The flag can be queried, set and cleared
programmatically as well. Whenever the flag changes state a <<Modified>> virtual
event is generated. See the edit modified widget command for more details.
the Undo MechanismThe text widget has an unlimited undo and redo mechanism
(when the -undo widget option is true) which records every insert and delete
action on a stack.
Boundaries (called "separators") are inserted between
edit actions. The purpose of these separators is to group inserts, deletes
and replaces into one compound edit action. When undoing a change everything
between two separators will be undone. The undone changes are then moved
to the redo stack, so that an undone edit can be redone again. The redo
stack is cleared whenever new edit actions are recorded on the undo stack.
The undo and redo stacks can be cleared to keep their depth under control.
Separators are inserted automatically when the -autoseparators widget option
is true. You can insert separators programmatically as well. If a separator
is already present at the top of the undo stack no other will be inserted.
That means that two separators on the undo stack are always separated
by at least one insert or delete action.
The undo mechanism is also linked
to the modified flag. This means that undoing or redoing changes can take
a modified text widget back to the unmodified state or vice versa. The
modified flag will be set automatically to the appropriate state. This
automatic coupling does not work when the modified flag has been set by
the user, until the flag has been reset again.
See below for the edit widget
command that controls the undo mechanism.
Widget CommandThe text command
creates a new Tcl command whose name is the same as the path name of the
text’s window. This command may be used to invoke various operations on
the widget. It has the following general form:
pathName option ?arg arg ...?
PathName is the name of the command, which is the same as the text widget’s
path name. Option and the args determine the exact behavior of the command.
The following commands are possible for text widgets:
pathName bbox index
Returns a list of four elements describing the screen area of the character
given by index. The first two elements of the list give the x and y coordinates
of the upper-left corner of the area occupied by the character, and the
last two elements give the width and height of the area. If the character
is only partially visible on the screen, then the return value reflects
just the visible part. If the character is not visible on the screen then
the return value is an empty list. pathName cget option Returns the current
value of the configuration option given by option. Option may have any of
the values accepted by the text command. pathName compare index1 op index2
Compares the indices given by index1 and index2 according to the relational
operator given by op, and returns 1 if the relationship is satisfied and
0 if it isn’t. Op must be one of the operators <, <=, ==, >=, >, or !=. If op
is == then 1 is returned if the two indices refer to the same character,
if op is < then 1 is returned if index1 refers to an earlier character in
the text than index2, and so on. pathName configure ?option? ?value option
value ...? Query or modify the configuration options of the widget. If no option
is specified, returns a list describing all of the available options for
pathName (see Tk_ConfigureInfo for information on the format of this list).
If option is specified with no value, then the command returns a list
describing the one named option (this list will be identical to the corresponding
sublist of the value returned if no option is specified). If one or more
option-value pairs are specified, then the command modifies the given widget
option(s) to have the given value(s); in this case the command returns
an empty string. Option may have any of the values accepted by the text
command. pathName debug ?boolean? If boolean is specified, then it must
have one of the true or false values accepted by Tcl_GetBoolean. If the
value is a true one then internal consistency checks will be turned on
in the B-tree code associated with text widgets. If boolean has a false value
then the debugging checks will be turned off. In either case the command
returns an empty string. If boolean is not specified then the command returns
on or off to indicate whether or not debugging is turned on. There is a
single debugging switch shared by all text widgets: turning debugging
on or off in any widget turns it on or off for all widgets. For widgets
with large amounts of text, the consistency checks may cause a noticeable
slow-down. When debugging is turned on, the drawing routines of the text
widget set the global variables tk_textRedraw and tk_textRelayout to the
lists of indices that are redrawn. The values of these variables are tested
by Tk’s test suite.
pathName delete index1 ?index2 ...? Delete a range of characters
from the text. If both index1 and index2 are specified, then delete all
the characters starting with the one given by index1 and stopping just
before index2 (i.e. the character at index2 is not deleted). If index2 doesn’t
specify a position later in the text than index1 then no characters are
deleted. If index2 isn’t specified then the single character at index1 is
deleted. It is not allowable to delete characters in a way that would leave
the text without a newline as the last character. The command returns an
empty string. If more indices are given, multiple ranges of text will be
deleted. All indices are first checked for validity before any deletions
are made. They are sorted and the text is removed from the last range to
the first range to deleted text does not cause an undesired index shifting
side-effects. If multiple ranges with the same start index are given, then
the longest range is used. If overlapping ranges are given, then they will
be merged into spans that do not cause deletion of text outside the given
ranges due to text shifted during deletion. pathName dlineinfo index Returns
a list with five elements describing the area occupied by the display line
containing index. The first two elements of the list give the x and y coordinates
of the upper-left corner of the area occupied by the line, the third and
fourth elements give the width and height of the area, and the fifth element
gives the position of the baseline for the line, measured down from the
top of the area. All of this information is measured in pixels. If the current
wrap mode is none and the line extends beyond the boundaries of the window,
the area returned reflects the entire area of the line, including the portions
that are out of the window. If the line is shorter than the full width of
the window then the area returned reflects just the portion of the line
that is occupied by characters and embedded windows. If the display line
containing index is not visible on the screen then the return value is
an empty list. pathName dump ?switches? index1 ?index2? Return the contents
of the text widget from index1 up to, but not including index2, including
the text and information about marks, tags, and embedded windows. If index2
is not specified, then it defaults to one character past index1. The information
is returned in the following format: key1 value1 index1 key2 value2 index2
...
The possible key values are text, mark, tagon, tagoff, image, and window.
The corresponding value is the text, mark name, tag name, image name,
or window name. The index information is the index of the start of the text,
mark, tag transition, image or window. One or more of the following switches
(or abbreviations thereof) may be specified to control the dump:
-all Return
information about all elements: text, marks, tags, images and windows. This
is the default. -command command Instead of returning the information as
the result of the dump operation, invoke the command on each element of
the text widget within the range. The command has three arguments appended
to it before it is evaluated: the key, value, and index. -image Include information
about images in the dump results. -mark Include information about marks in
the dump results. -tag Include information about tag transitions in the dump
results. Tag information is returned as tagon and tagoff elements that indicate
the begin and end of each range of each tag, respectively. -text Include
information about text in the dump results. The value is the text up to
the next element or the end of range indicated by index2. A text element
does not span newlines. A multi-line block of text that contains no marks
or tag transitions will still be dumped as a set of text segments that
each end with a newline. The newline is part of the value. -window Include
information about embedded windows in the dump results. The value of a window
is its Tk pathname, unless the window has not been created yet. (It must
have a create script.) In this case an empty string is returned, and you
must query the window by its index position to get more information. pathName
edit option ?arg arg ...? This command controls the undo mechanism and the
modified flag. The exact behavior of the command depends on the option
argument that follows the edit argument. The following forms of the command
are currently supported: pathName edit modified ?boolean? If boolean is
not specified, returns the modified flag of the widget. The insert, delete,
edit undo and edit redo commands or the user can set or clear the modified
flag. If boolean is specified, sets the modified flag of the widget to
boolean. pathName edit redo When the -undo option is true, reapplies the
last undone edits provided no other edits were done since then. Generates
an error when the redo stack is empty. Does nothing when the -undo option
is false. pathName edit reset Clears the undo and redo stacks. pathName edit
separator Inserts a separator (boundary) on the undo stack. Does nothing
when the -undo option is false. pathName edit undo Undoes the last edit action
when the -undo option is true. An edit action is defined as all the insert
and delete commands that are recorded on the undo stack in between two
separators. Generates an error when the undo stack is empty. Does nothing
when the -undo option is false. pathName get index1 ?index2 ...? Return a range
of characters from the text. The return value will be all the characters
in the text starting with the one whose index is index1 and ending just
before the one whose index is index2 (the character at index2 will not
be returned). If index2 is omitted then the single character at index1 is
returned. If there are no characters in the specified range (e.g. index1 is
past the end of the file or index2 is less than or equal to index1) then
an empty string is returned. If the specified range contains embedded windows,
no information about them is included in the returned string. If multiple
index pairs are given, multiple ranges of text will be returned in a list.
Invalid ranges will not be represented with empty strings in the list.
The ranges are returned in the order passed to get. pathName image option
?arg arg ...? This command is used to manipulate embedded images. The behavior
of the command depends on the option argument that follows the tag argument.
The following forms of the command are currently supported: pathName image
cget index option Returns the value of a configuration option for an embedded
image. Index identifies the embedded image, and option specifies a particular
configuration option, which must be one of the ones listed in the section
EMBEDDED IMAGES. pathName image configure index ?option value ...? Query or
modify the configuration options for an embedded image. If no option is
specified, returns a list describing all of the available options for the
embedded image at index (see Tk_ConfigureInfo for information on the format
of this list). If option is specified with no value, then the command returns
a list describing the one named option (this list will be identical to
the corresponding sublist of the value returned if no option is specified).
If one or more option-value pairs are specified, then the command modifies
the given option(s) to have the given value(s); in this case the command
returns an empty string. See EMBEDDED IMAGES for information on the options
that are supported. pathName image create index ?option value ...? This command
creates a new image annotation, which will appear in the text at the position
given by index. Any number of option-value pairs may be specified to configure
the annotation. Returns a unique identifier that may be used as an index
to refer to this image. See EMBEDDED IMAGES for information on the options
that are supported, and a description of the identifier returned. pathName
image names Returns a list whose elements are the names of all image instances
currently embedded in window. pathName index index Returns the position
corresponding to index in the form line.char where line is the line number
and char is the character number. Index may have any of the forms described
under INDICES above. pathName insert index chars ?tagList chars tagList
...? Inserts all of the chars arguments just before the character at index.
If index refers to the end of the text (the character after the last newline)
then the new text is inserted just before the last newline instead. If there
is a single chars argument and no tagList, then the new text will receive
any tags that are present on both the character before and the character
after the insertion point; if a tag is present on only one of these characters
then it will not be applied to the new text. If tagList is specified then
it consists of a list of tag names; the new characters will receive all
of the tags in this list and no others, regardless of the tags present
around the insertion point. If multiple chars-tagList argument pairs are
present, they produce the same effect as if a separate insert widget command
had been issued for each pair, in order. The last tagList argument may be
omitted. pathName mark option ?arg arg ...? This command is used to manipulate
marks. The exact behavior of the command depends on the option argument
that follows the mark argument. The following forms of the command are
currently supported: pathName mark gravity markName ?direction? If direction
is not specified, returns left or right to indicate which of its adjacent
characters markName is attached to. If direction is specified, it must be
left or right; the gravity of markName is set to the given value. pathName
mark names Returns a list whose elements are the names of all the marks
that are currently set. pathName mark next index Returns the name of the
next mark at or after index. If index is specified in numerical form, then
the search for the next mark begins at that index. If index is the name
of a mark, then the search for the next mark begins immediately after that
mark. This can still return a mark at the same position if there are multiple
marks at the same index. These semantics mean that the mark next operation
can be used to step through all the marks in a text widget in the same
order as the mark information returned by the dump operation. If a mark
has been set to the special end index, then it appears to be after end
with respect to the mark next operation. An empty string is returned if
there are no marks after index. pathName mark previous index Returns the
name of the mark at or before index. If index is specified in numerical
form, then the search for the previous mark begins with the character just
before that index. If index is the name of a mark, then the search for the
next mark begins immediately before that mark. This can still return a mark
at the same position if there are multiple marks at the same index. These
semantics mean that the mark previous operation can be used to step through
all the marks in a text widget in the reverse order as the mark information
returned by the dump operation. An empty string is returned if there are
no marks before index. pathName mark set markName index Sets the mark named
markName to a position just before the character at index. If markName already
exists, it is moved from its old position; if it doesn’t exist, a new mark
is created. This command returns an empty string. pathName mark unset markName
?markName markName ...? Remove the mark corresponding to each of the markName
arguments. The removed marks will not be usable in indices and will not
be returned by future calls to ‘‘pathName mark names’’. This command returns
an empty string. pathName scan option args This command is used to implement
scanning on texts. It has two forms, depending on option: pathName scan
mark x y Records x and y and the current view in the text window, for use
in conjunction with later scan dragto commands. Typically this command is
associated with a mouse button press in the widget. It returns an empty
string. pathName scan dragto x y This command computes the difference between
its x and y arguments and the x and y arguments to the last scan mark command
for the widget. It then adjusts the view by 10 times the difference in coordinates.
This command is typically associated with mouse motion events in the widget,
to produce the effect of dragging the text at high speed through the window.
The return value is an empty string. pathName search ?switches? pattern
index ?stopIndex? Searches the text in pathName starting at index for a
range of characters that matches pattern. If a match is found, the index
of the first character in the match is returned as result; otherwise an
empty string is returned. One or more of the following switches (or abbreviations
thereof) may be specified to control the search: -forwards The search will
proceed forward through the text, finding the first matching range starting
at or after the position given by index. This is the default. -backwards The
search will proceed backward through the text, finding the matching range
closest to index whose first character is before index. -exact Use exact
matching: the characters in the matching range must be identical to those
in pattern. This is the default. -regexp Treat pattern as a regular expression
and match it against the text using the rules for regular expressions (see
the regexp command for details). -nocase Ignore case differences between
the pattern and the text. -count varName The argument following -count gives
the name of a variable; if a match is found, the number of index positions
between beginning and end of the matching range will be stored in the variable.
If there are no embedded images or windows in the matching range (and
there are no elided characters if -elide is not given), this is equivalent
to the number of characters matched. In either case, the range matchIdx
to matchIdx + $count chars will return the entire matched text. -elide Find
elided (hidden) text as well. By default only displayed text is searched.
-- This switch has no effect except to terminate the list of switches: the
next argument will be treated as pattern even if it starts with -. The matching
range must be entirely within a single line of text. For regular expression
matching the newlines are removed from the ends of the lines before matching:
use the $ feature in regular expressions to match the end of a line. For
exact matching the newlines are retained. If stopIndex is specified, the
search stops at that index: for forward searches, no match at or after
stopIndex will be considered; for backward searches, no match earlier
in the text than stopIndex will be considered. If stopIndex is omitted,
the entire text will be searched: when the beginning or end of the text
is reached, the search continues at the other end until the starting location
is reached again; if stopIndex is specified, no wrap-around will occur.
pathName see index Adjusts the view in the window so that the character
given by index is completely visible. If index is already visible then the
command does nothing. If index is a short distance out of view, the command
adjusts the view just enough to make index visible at the edge of the window.
If index is far out of view, then the command centers index in the window.
pathName tag option ?arg arg ...? This command is used to manipulate tags.
The exact behavior of the command depends on the option argument that
follows the tag argument. The following forms of the command are currently
supported: pathName tag add tagName index1 ?index2 index1 index2 ...? Associate
the tag tagName with all of the characters starting with index1 and ending
just before index2 (the character at index2 isn’t tagged). A single command
may contain any number of index1-index2 pairs. If the last index2 is omitted
then the single character at index1 is tagged. If there are no characters
in the specified range (e.g. index1 is past the end of the file or index2
is less than or equal to index1) then the command has no effect. pathName
tag bind tagName ?sequence? ?script? This command associates script with
the tag given by tagName. Whenever the event sequence given by sequence
occurs for a character that has been tagged with tagName, the script will
be invoked. This widget command is similar to the bind command except that
it operates on characters in a text rather than entire widgets. See the
bind manual entry for complete details on the syntax of sequence and the
substitutions performed on script before invoking it. If all arguments are
specified then a new binding is created, replacing any existing binding
for the same sequence and tagName (if the first character of script is
‘‘+’’ then script augments an existing binding rather than replacing it). In
this case the return value is an empty string. If script is omitted then
the command returns the script associated with tagName and sequence (an
error occurs if there is no such binding). If both script and sequence are
omitted then the command returns a list of all the sequences for which
bindings have been defined for tagName. The only events for which bindings
may be specified are those related to the mouse and keyboard (such as Enter,
Leave, ButtonPress, Motion, and KeyPress) or virtual events. Event bindings
for a text widget use the current mark described under MARKS above. An
Enter event triggers for a tag when the tag first becomes present on the
current character, and a Leave event triggers for a tag when it ceases
to be present on the current character. Enter and Leave events can happen
either because the current mark moved or because the character at that
position changed. Note that these events are different than Enter and Leave
events for windows. Mouse and keyboard events are directed to the current
character. If a virtual event is used in a binding, that binding can trigger
only if the virtual event is defined by an underlying mouse-related or keyboard-related
event.
It is possible for the current character to have multiple tags, and
for each of them to have a binding for a particular event sequence. When
this occurs, one binding is invoked for each tag, in order from lowest-priority
to highest priority. If there are multiple matching bindings for a single
tag, then the most specific binding is chosen (see the manual entry for
the bind command for details). continue and break commands within binding
scripts are processed in the same way as for bindings created with the
bind command.
If bindings are created for the widget as a whole using the
bind command, then those bindings will supplement the tag bindings. The
tag bindings will be invoked first, followed by bindings for the window
as a whole.
pathName tag cget tagName option This command returns the current
value of the option named option associated with the tag given by tagName.
Option may have any of the values accepted by the tag configure widget
command. pathName tag configure tagName ?option? ?value? ?option value ...?
This command is similar to the configure widget command except that it
modifies options associated with the tag given by tagName instead of modifying
options for the overall text widget. If no option is specified, the command
returns a list describing all of the available options for tagName (see
Tk_ConfigureInfo for information on the format of this list). If option
is specified with no value, then the command returns a list describing
the one named option (this list will be identical to the corresponding
sublist of the value returned if no option is specified). If one or more
option-value pairs are specified, then the command modifies the given option(s)
to have the given value(s) in tagName; in this case the command returns
an empty string. See TAGS above for details on the options available for
tags. pathName tag delete tagName ?tagName ...? Deletes all tag information
for each of the tagName arguments. The command removes the tags from all
characters in the file and also deletes any other information associated
with the tags, such as bindings and display information. The command returns
an empty string. pathName tag lower tagName ?belowThis? Changes the priority
of tag tagName so that it is just lower in priority than the tag whose
name is belowThis. If belowThis is omitted, then tagName’s priority is changed
to make it lowest priority of all tags. pathName tag names ?index? Returns
a list whose elements are the names of all the tags that are active at
the character position given by index. If index is omitted, then the return
value will describe all of the tags that exist for the text (this includes
all tags that have been named in a ‘‘pathName tag’’ widget command but haven’t
been deleted by a ‘‘pathName tag delete’’ widget command, even if no characters
are currently marked with the tag). The list will be sorted in order from
lowest priority to highest priority. pathName tag nextrange tagName index1
?index2? This command searches the text for a range of characters tagged
with tagName where the first character of the range is no earlier than
the character at index1 and no later than the character just before index2
(a range starting at index2 will not be considered). If several matching
ranges exist, the first one is chosen. The command’s return value is a list
containing two elements, which are the index of the first character of
the range and the index of the character just after the last one in the
range. If no matching range is found then the return value is an empty string.
If index2 is not given then it defaults to the end of the text. pathName
tag prevrange tagName index1 ?index2? This command searches the text for
a range of characters tagged with tagName where the first character of
the range is before the character at index1 and no earlier than the character
at index2 (a range starting at index2 will be considered). If several matching
ranges exist, the one closest to index1 is chosen. The command’s return value
is a list containing two elements, which are the index of the first character
of the range and the index of the character just after the last one in
the range. If no matching range is found then the return value is an empty
string. If index2 is not given then it defaults to the beginning of the
text. pathName tag raise tagName ?aboveThis? Changes the priority of tag
tagName so that it is just higher in priority than the tag whose name is
aboveThis. If aboveThis is omitted, then tagName’s priority is changed to
make it highest priority of all tags. pathName tag ranges tagName Returns
a list describing all of the ranges of text that have been tagged with
tagName. The first two elements of the list describe the first tagged range
in the text, the next two elements describe the second range, and so on.
The first element of each pair contains the index of the first character
of the range, and the second element of the pair contains the index of
the character just after the last one in the range. If there are no characters
tagged with tag then an empty string is returned. pathName tag remove tagName
index1 ?index2 index1 index2 ...? Remove the tag tagName from all of the characters
starting at index1 and ending just before index2 (the character at index2
isn’t affected). A single command may contain any number of index1-index2
pairs. If the last index2 is omitted then the single character at index1
is tagged. If there are no characters in the specified range (e.g. index1
is past the end of the file or index2 is less than or equal to index1)
then the command has no effect. This command returns an empty string. pathName
window option ?arg arg ...? This command is used to manipulate embedded windows.
The behavior of the command depends on the option argument that follows
the tag argument. The following forms of the command are currently supported:
pathName window cget index option Returns the value of a configuration
option for an embedded window. Index identifies the embedded window, and
option specifies a particular configuration option, which must be one of
the ones listed in the section EMBEDDED WINDOWS. pathName window configure
index ?option value ...? Query or modify the configuration options for an
embedded window. If no option is specified, returns a list describing all
of the available options for the embedded window at index (see Tk_ConfigureInfo
for information on the format of this list). If option is specified with
no value, then the command returns a list describing the one named option
(this list will be identical to the corresponding sublist of the value
returned if no option is specified). If one or more option-value pairs are
specified, then the command modifies the given option(s) to have the given
value(s); in this case the command returns an empty string. See EMBEDDED
WINDOWS for information on the options that are supported. pathName window
create index ?option value ...? This command creates a new window annotation,
which will appear in the text at the position given by index. Any number
of option-value pairs may be specified to configure the annotation. See EMBEDDED
WINDOWS for information on the options that are supported. Returns an empty
string. pathName window names Returns a list whose elements are the names
of all windows currently embedded in window. pathName xview option args
This command is used to query and change the horizontal position of the
text in the widget’s window. It can take any of the following forms: pathName
xview Returns a list containing two elements. Each element is a real fraction
between 0 and 1; together they describe the portion of the document’s horizontal
span that is visible in the window. For example, if the first element is
.2 and the second element is .6, 20% of the text is off-screen to the left,
the middle 40% is visible in the window, and 40% of the text is off-screen
to the right. The fractions refer only to the lines that are actually visible
in the window: if the lines in the window are all very short, so that
they are entirely visible, the returned fractions will be 0 and 1, even
if there are other lines in the text that are much wider than the window.
These are the same values passed to scrollbars via the -xscrollcommand option.
pathName xview moveto fraction Adjusts the view in the window so that fraction
of the horizontal span of the text is off-screen to the left. Fraction is
a fraction between 0 and 1. pathName xview scroll number what This command
shifts the view in the window left or right according to number and what.
Number must be an integer. What must be either units or pages or an abbreviation
of one of these. If what is units, the view adjusts left or right by number
average-width characters on the display; if it is pages then the view adjusts
by number screenfuls. If number is negative then characters farther to the
left become visible; if it is positive then characters farther to the
right become visible. pathName yview ?args? This command is used to query
and change the vertical position of the text in the widget’s window. It can
take any of the following forms: pathName yview Returns a list containing
two elements, both of which are real fractions between 0 and 1. The first
element gives the position of the first character in the top line in the
window, relative to the text as a whole (0.5 means it is halfway through
the text, for example). The second element gives the position of the character
just after the last one in the bottom line of the window, relative to the
text as a whole. These are the same values passed to scrollbars via the
-yscrollcommand option. pathName yview moveto fraction Adjusts the view in
the window so that the character given by fraction appears on the top line
of the window. Fraction is a fraction between 0 and 1; 0 indicates the
first character in the text, 0.33 indicates the character one-third the way
through the text, and so on. pathName yview scroll number what This command
adjust the view in the window up or down according to number and what. Number
must be an integer. What must be either units or pages. If what is units,
the view adjusts up or down by number lines on the display; if it is pages
then the view adjusts by number screenfuls. If number is negative then earlier
positions in the text become visible; if it is positive then later positions
in the text become visible. pathName yview ?-pickplace? index Changes the
view in the widget’s window to make index visible. If the -pickplace option
isn’t specified then index will appear at the top of the window. If -pickplace
is specified then the widget chooses where index appears in the window:
[1]If index is already visible somewhere in the window then the command
does nothing. [2]If index is only a few lines off-screen above the window
then it will be positioned at the top of the window. [3]If index is only
a few lines off-screen below the window then it will be positioned at the
bottom of the window. [4]Otherwise, index will be centered in the window.
The -pickplace option has been obsoleted by the see widget command (see
handles both x- and y-motion to make a location visible, whereas -pickplace
only handles motion in y).
pathName yview number This command makes the
first character on the line after the one given by number visible at the
top of the window. Number must be an integer. This command used to be used
for scrolling, but now it is obsolete. BindingsTk automatically creates
class bindings for texts that give them the following default behavior.
In the descriptions below, ‘‘word’’ is dependent on the value of the tcl_wordchars
variable. See tclvars(n).
[1]Clicking mouse button 1 positions the insertion
cursor just before the character underneath the mouse cursor, sets the
input focus to this widget, and clears any selection in the widget. Dragging
with mouse button 1 strokes out a selection between the insertion cursor
and the character under the mouse. [2]Double-clicking with mouse button 1
selects the word under the mouse and positions the insertion cursor at
the end of the word. Dragging after a double click will stroke out a selection
consisting of whole words. [3]Triple-clicking with mouse button 1 selects
the line under the mouse and positions the insertion cursor at the end
of the line. Dragging after a triple click will stroke out a selection consisting
of whole lines. [4]The ends of the selection can be adjusted by dragging
with mouse button 1 while the Shift key is down; this will adjust the
end of the selection that was nearest to the mouse cursor when button 1
was pressed. If the button is double-clicked before dragging then the selection
will be adjusted in units of whole words; if it is triple-clicked then
the selection will be adjusted in units of whole lines. [5]Clicking mouse
button 1 with the Control key down will reposition the insertion cursor
without affecting the selection. [6]If any normal printing characters are
typed, they are inserted at the point of the insertion cursor. [7]The view
in the widget can be adjusted by dragging with mouse button 2. If mouse
button 2 is clicked without moving the mouse, the selection is copied into
the text at the position of the mouse cursor. The Insert key also inserts
the selection, but at the position of the insertion cursor. [8]If the mouse
is dragged out of the widget while button 1 is pressed, the entry will
automatically scroll to make more text visible (if there is more text off-screen
on the side where the mouse left the window). [9]The Left and Right keys
move the insertion cursor one character to the left or right; they also
clear any selection in the text. If Left or Right is typed with the Shift
key down, then the insertion cursor moves and the selection is extended
to include the new character. Control-Left and Control-Right move the insertion
cursor by words, and Control-Shift-Left and Control-Shift-Right move the insertion
cursor by words and also extend the selection. Control-b and Control-f behave
the same as Left and Right, respectively. Meta-b and Meta-f behave the same
as Control-Left and Control-Right, respectively. [10]The Up and Down keys
move the insertion cursor one line up or down and clear any selection in
the text. If Up or Right is typed with the Shift key down, then the insertion
cursor moves and the selection is extended to include the new character.
Control-Up and Control-Down move the insertion cursor by paragraphs (groups
of lines separated by blank lines), and Control-Shift-Up and Control-Shift-Down
move the insertion cursor by paragraphs and also extend the selection. Control-p
and Control-n behave the same as Up and Down, respectively. [11]The Next
and Prior keys move the insertion cursor forward or backwards by one screenful
and clear any selection in the text. If the Shift key is held down while
Next or Prior is typed, then the selection is extended to include the new
character. Control-v moves the view down one screenful without moving the
insertion cursor or adjusting the selection. [12]Control-Next and Control-Prior
scroll the view right or left by one page without moving the insertion
cursor or affecting the selection. [13]Home and Control-a move the insertion
cursor to the beginning of its line and clear any selection in the widget.
Shift-Home moves the insertion cursor to the beginning of the line and also
extends the selection to that point. [14]End and Control-e move the insertion
cursor to the end of the line and clear any selection in the widget. Shift-End
moves the cursor to the end of the line and extends the selection to that
point. [15]Control-Home and Meta-< move the insertion cursor to the beginning
of the text and clear any selection in the widget. Control-Shift-Home moves
the insertion cursor to the beginning of the text and also extends the
selection to that point. [16]Control-End and Meta-> move the insertion cursor
to the end of the text and clear any selection in the widget. Control-Shift-End
moves the cursor to the end of the text and extends the selection to that
point. [17]The Select key and Control-Space set the selection anchor to the
position of the insertion cursor. They don’t affect the current selection.
Shift-Select and Control-Shift-Space adjust the selection to the current position
of the insertion cursor, selecting from the anchor to the insertion cursor
if there was not any selection previously. [18]Control-/ selects the entire
contents of the widget. [19]Control-\ clears any selection in the widget. [20]The
F16 key (labelled Copy on many Sun workstations) or Meta-w copies the selection
in the widget to the clipboard, if there is a selection. This action is
carried out by the command tk_textCopy. [21]The F20 key (labelled Cut on
many Sun workstations) or Control-w copies the selection in the widget to
the clipboard and deletes the selection. This action is carried out by the
command tk_textCut. If there is no selection in the widget then these keys
have no effect. [22]The F18 key (labelled Paste on many Sun workstations)
or Control-y inserts the contents of the clipboard at the position of the
insertion cursor. This action is carried out by the command tk_textPaste.
[23]The Delete key deletes the selection, if there is one in the widget.
If there is no selection, it deletes the character to the right of the
insertion cursor. [24]Backspace and Control-h delete the selection, if there
is one in the widget. If there is no selection, they delete the character
to the left of the insertion cursor. [25]Control-d deletes the character
to the right of the insertion cursor. [26]Meta-d deletes the word to the
right of the insertion cursor. [27]Control-k deletes from the insertion cursor
to the end of its line; if the insertion cursor is already at the end of
a line, then Control-k deletes the newline character. [28]Control-o opens
a new line by inserting a newline character in front of the insertion cursor
without moving the insertion cursor. [29]Meta-backspace and Meta-Delete delete
the word to the left of the insertion cursor. [30]Control-x deletes whatever
is selected in the text widget after copying it to the clipboard. [31]Control-t
reverses the order of the two characters to the right of the insertion
cursor. [32]Control-z (and Control-underscore on UNIX when tk_strictMotif
is true) undoes the last edit action if the -undo option is true. Does nothing
otherwise. [33]Control-Z (or Control-y on Windows) reapplies the last undone
edit action if the -undo option is true. Does nothing otherwise. If the widget
is disabled using the -state option, then its view can still be adjusted
and text can still be selected, but no insertion cursor will be displayed
and no text modifications will take place.
The behavior of texts can be
changed by defining new bindings for individual widgets or by redefining
the class bindings.
Performance IssuesText widgets should run efficiently
under a variety of conditions. The text widget uses about 2-3 bytes of main
memory for each byte of text, so texts containing a megabyte or more should
be practical on most workstations. Text is represented internally with a
modified B-tree structure that makes operations relatively efficient even
with large texts. Tags are included in the B-tree structure in a way that
allows tags to span large ranges or have many disjoint smaller ranges without
loss of efficiency. Marks are also implemented in a way that allows large
numbers of marks. In most cases it is fine to have large numbers of unique
tags, or a tag that has many distinct ranges.
One performance problem can
arise if you have hundreds or thousands of different tags that all have
the following characteristics: the first and last ranges of each tag are
near the beginning and end of the text, respectively, or a single tag range
covers most of the text widget. The cost of adding and deleting tags like
this is proportional to the number of other tags with the same properties.
In contrast, there is no problem with having thousands of distinct tags
if their overall ranges are localized and spread uniformly throughout the
text.
Very long text lines can be expensive, especially if they have many
marks and tags within them.
The display line with the insert cursor is redrawn
each time the cursor blinks, which causes a steady stream of graphics traffic.
Set the insertOffTime attribute to 0 avoid this.
See Alsoentry(n), scrollbar(n)
Keywordstext, widget, tkvars
![[Go to CFHT Home Page]](/images/cfht-icon.gif){kind=icon}
Man Pages 
Back to Software Index 
Manpage Top Level