NAME

text - Create and manipulate text widgets

SYNOPSIS

text pathName ?options?

STANDARD OPTIONS

-background or -bg, background, Background
-borderwidth or -bd, borderWidth, BorderWidth
-cursor, cursor, Cursor
-exportselection, exportSelection, ExportSelection
-font, font, Font
-foreground or -fg, foreground, Foreground
-highlightbackground, highlightBackground, HighlightBackground
-highlightcolor, highlightColor, HighlightColor
-highlightthickness, highlightThickness, HighlightThickness
-insertbackground, insertBackground, Foreground
-insertborderwidth, insertBorderWidth, BorderWidth
-insertofftime, insertOffTime, OffTime
-insertontime, insertOnTime, OnTime
-insertwidth, insertWidth, InsertWidth
-padx, padX, Pad
-pady, padY, Pad
-relief, relief, Relief
-selectbackground, selectBackground, Foreground
-selectborderwidth, selectBorderWidth, BorderWidth
-selectforeground, selectForeground, Background
-setgrid, setGrid, SetGrid
-takefocus, takeFocus, TakeFocus
-xscrollcommand, xScrollCommand, ScrollCommand
-yscrollcommand, yScrollCommand, ScrollCommand

WIDGET-SPECIFIC OPTIONS

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: -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 overriden 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 overriden 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 overriden 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 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. 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: -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.

DESCRIPTION

The 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 marks, which are floating markers in the text. 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.

INDICES

Many 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.
.VS
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.

TAGS

The 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 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.
-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_GetFontStruct.
-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 Tk_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 Tk_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.

MARKS

The 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 right of the mark. 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 WINDOWS

The 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 IMAGES

The 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 widh 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 SELECTION

Selection 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.

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 CURSOR

The 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.

WIDGET COMMAND

The 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.
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.
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: