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diff --git a/Master/tlpkg/tlperl0/lib/Tk/Text.pod b/Master/tlpkg/tlperl0/lib/Tk/Text.pod deleted file mode 100755 index b6db20423f3..00000000000 --- a/Master/tlpkg/tlperl0/lib/Tk/Text.pod +++ /dev/null @@ -1,2215 +0,0 @@ -# Copyright (c) 1992 The Regents of the University of California. -# Copyright (c) 1994-1996 Sun Microsystems, Inc. -# Copyright (c) 2002 O'Reilly & Associates Inc. -# See the file "license.terms" for information on usage and redistribution -# of this file, and for a DISCLAIMER OF ALL WARRANTIES. -# -# - -=head1 NAME - -Tk::Text - Create and manipulate Text widgets - -=for category Tk Widget Classes - -=head1 SYNOPSIS - -B<text> $text ?I<options>? - -B<-background> B<-highlightbackground> B<-insertontime> B<-selectborderwidth> -B<-borderwidth> B<-highlightcolor> B<-insertwidth> B<-selectforeground> -B<-cursor> B<-highlightthickness> B<-padx> B<-setgrid> -B<-exportselection> B<-insertbackground> B<-pady> B<-takefocus> -B<-font> B<-insertborderwidth> B<-relief> B<-xscrollcommand> -B<-foreground> B<-insertofftime> B<-selectbackground> B<-yscrollcommand> - -=head1 WIDGET-SPECIFIC OPTIONS - -=over 4 - -=item Name: B<height> - -=item Class: B<Height> - -=item Switch: B<-height> - -Specifies the desired height for the window, in units of characters -in the font given by the B<-font> option. -Must be at least one. - -=item Name: B<spacing1> - -=item Class: B<Spacing1> - -=item Switch: B<-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 B<-spacing1> options in -tags. - -=item Name: B<spacing2> - -=item Class: B<Spacing2> - -=item Switch: B<-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 B<-spacing2> options in -tags. - -=item Name: B<spacing3> - -=item Class: B<Spacing3> - -=item Switch: B<-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 B<-spacing3> options in -tags. - -=item Name: B<state> - -=item Class: B<State> - -=item Switch: B<-state> - -Specifies one of two states for the text: B<normal> or B<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. - -=item Name: B<tabs> - -=item Class: B<Tabs> - -=item Switch: B<-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 B<left>, B<right>, B<center>, -or B<numeric>, which specifies how to justify -text relative to the tab stop. B<Left> is the default; it causes -the text following the tab character to be positioned with its left edge -at the tab position. B<Right> means that the right edge of the text -following the tab character is positioned at the tab position, and -B<center> means that the text is centered at the tab position. -B<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, B<-tabs =E<gt> [qw/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 B<tabs> option may be overridden by B<-tabs> -options in tags. -If no B<-tabs> option is specified, or if it is specified as -an empty list, then Tk uses default tabs spaced every eight -(average size) characters. - -=item Name: B<width> - -=item Class: B<Width> - -=item Switch: B<-width> - -Specifies the desired width for the window in units of characters -in the font given by the B<-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. - -=item Name: B<wrap> - -=item Class: B<Wrap> - -=item Switch: B<-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 B<none> or B<char> or B<word>. -A wrap mode of B<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 B<char> mode a screen line break may occur after any character; -in B<word> mode a line break will only be made at word boundaries. - -=back - -=head1 DESCRIPTION - -The B<Text> method creates a new window (given by the -$text 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 B<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, L<perl/Tk callbacks|Tk::callbacks> 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 L<"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 L<"MARKS"> below for more details. - -The third form of annotation allows arbitrary windows to be -embedded in a text widget. -See L<"EMBEDDED WINDOWS"> below for more details. - -The fourth form of annotation allows Tk images to be embedded in a text -widget. -See L<"EMBEDDED IMAGES"> below for more details. - -The Perl/Tk B<Text> widget does not support undo/redo, use the B<TextUndo> -widget instead. - -=head1 INDICES - -Many of the methods 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 I<base> gives a starting point and the I<modifier>s -adjust the index from the starting point (e.g. move forward or -backward one character). Every index must contain a I<base>, -but the I<modifier>s are optional. - -The I<base> for an index must have one of the following forms: - -=over 4 - -=item I<line>B<.>I<char> - -Indicates I<char>'th character on line I<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 I<char> is B<end> then it refers to the newline character -that ends the line. - -=item B<@>I<x>B<,>I<y> - -Indicates the character that covers the pixel whose x and y coordinates -within the text's window are I<x> and I<y>. - -=item B<end> - -Indicates the end of the text (the character just after the last -newline). - -=item I<mark> - -Indicates the character just after the mark whose name is I<mark>. - -=item I<tag>B<.first> - -Indicates the first character in the text that has been tagged with -I<tag>. -This form generates an error if no characters are currently tagged -with I<tag>. - -=item I<tag>B<.last> - -Indicates the character just after the last one in the text that has -been tagged with I<tag>. -This form generates an error if no characters are currently tagged -with I<tag>. - -=item I<$widget> - -Indicates the position of the embedded window referenced by I<$widget>. -This form generates an error if I<$widget> does not reference to an -embedded window. - -=item I<imageName> - -Indicates the position of the embedded image whose name is -I<imageName>. -This form generates an error if there is no embedded image -by the given name. - -If the I<base> could match more than one of the above forms, such -as a I<mark> and I<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 B<chars> and B<wordend> -may be abbreviated as long as the abbreviation is unambiguous. - -=item B<+ >I<count>B< chars> - -Adjust the index forward by I<count> characters, moving to later -lines in the text if necessary. If there are fewer than I<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 I<count> are optional. - -=item B<- >I<count>B< chars> - -Adjust the index backward by I<count> characters, moving to earlier -lines in the text if necessary. If there are fewer than I<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 I<count> are optional. - -=item B<+ >I<count>B< lines> - -Adjust the index forward by I<count> lines, retaining the same -character position within the line. If there are fewer than I<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 I<count> are optional. - -=item B<- >I<count>B< lines> - -Adjust the index backward by I<count> lines, retaining the same -character position within the line. If there are fewer than I<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 I<count> are optional. - -=item B<linestart> - -Adjust the index to refer to the first character on the line. - -=item B<lineend> - -Adjust the index to refer to the last character on the line (the newline). - -=item B<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. - -=item B<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 ``B<end - 1 chars>'' -refers to the next-to-last character in the text and -``B<insert wordstart - 1 c>'' refers to the character just before -the first one in the word containing the insertion cursor. - -=back - -=head1 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), B<+>, or B<->: -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 callbacks to it), it is given -a priority higher than any existing tag. -The priority order of tags may be redefined using the -``I<$text>-E<gt>B<tagRaise>'' and ``I<$text>-E<gt>B<tagLower>'' -methods. - -Tags serve three purposes in text widgets. -First, they control the way information is displayed on the screen. -By default, characters are displayed as determined by the -B<background>, B<font>, and B<foreground> options for the -text widget. -However, display options may be associated with individual tags -using the ``I<$text>-E<gt>B<tagConfigure>'' method. -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: - -=over 4 - -=item B<-background> =E<gt> I<color> - -I<Color> specifies the background color to use for characters -associated with the tag. -It may have any of the forms accepted by B<Tk_GetColor>. - -=item B<-bgstipple> =E<gt> I<bitmap> - -I<Bitmap> specifies a bitmap that is used as a stipple pattern -for the background. -It may have any of the forms accepted by B<Tk_GetBitmap>. -If I<bitmap> hasn't been specified, or if it is specified -as an empty string, then a solid fill will be used for the -background. - -=item B<-borderwidth> =E<gt> I<pixels> - -I<Pixels> specifies the width of a 3-D border to draw around -the background. -It may have any of the forms accepted by B<Tk_GetPixels>. -This option is used in conjunction with the B<-relief> -option to give a 3-D appearance to the background for characters; -it is ignored unless the B<-background> option -has been set for the tag. - -=item B<-elide> =E<gt> 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. - -=item B<-data> =E<gt> I<value> - -Allows an arbitrary perl scalar I<value> to be associated with the tag. - -=item B<-fgstipple> =E<gt> I<bitmap> - -I<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 B<Tk_GetBitmap>. -If I<bitmap> hasn't been specified, or if it is specified -as an empty string, then a solid fill will be used. - -=item B<-font> =E<gt> I<fontName> - -I<FontName> is the name of a font to use for drawing characters. -It may have any of the forms accepted by B<Tk_GetFontStruct>. - -=item B<-foreground> =E<gt> I<color> - -I<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 B<Tk_GetColor>. - -=item B<-justify> =E<gt> I<justify> - -If the first character of a display line has a tag for which this -option has been specified, then I<justify> determines how to -justify the line. -It must be one of B<left>, B<right>, or B<center>. -If a line wraps, then the justification for each line on the -display is determined by the first character of that display line. - -=item B<-lmargin1> =E<gt> I<pixels> - -If the first character of a text line has a tag for which this -option has been specified, then I<pixels> specifies how -much the line should be indented from the left edge of the -window. -I<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 B<-lmargin2> option controls -the indentation for subsequent lines. - -=item B<-lmargin2> =E<gt> I<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 -I<pixels> specifies how much the line should be indented from -the left edge of the window. -I<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. - -=item B<-offset> =E<gt> I<pixels> - -I<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. -I<Pixels> may have any of the standard forms for screen -distances. - -=item B<-overstrike> =E<gt> I<boolean> - -Specifies whether or not to draw a horizontal rule through -the middle of characters. -I<Boolean> may have any of the forms accepted by B<Tk_GetBoolean>. - -=item B<-relief> =E<gt> I<relief> - -I<Relief> specifies the 3-D relief to use for drawing backgrounds, -in any of the forms accepted by B<Tk_GetRelief>. -This option is used in conjunction with the B<-borderwidth> -option to give a 3-D appearance to the background for characters; -it is ignored unless the B<-background> option -has been set for the tag. - -=item B<-rmargin> =E<gt> I<pixels> - -If the first character of a display line has a tag for which this -option has been specified, then I<pixels> specifies how wide -a margin to leave between the end of the line and the right -edge of the window. -I<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. - -=item B<-spacing1> =E<gt> I<pixels> - -I<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. - -=item B<-spacing2> =E<gt> I<pixels> - -For lines that wrap, this option specifies how much additional -space to leave between the display lines for a single text line. -I<Pixels> may have any of the standard forms for screen -distances. - -=item B<-spacing3> =E<gt> I<pixels> - -I<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. - -=item B<-tabs> =E<gt> I<tabList> - -I<TabList> specifies a set of tab stops in the same form -as for the B<-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 B<-tabs => " ">, then it requests -default 8-character tabs as described for the B<tabs> -widget option. - -=item B<-underline> =E<gt> I<boolean> - -I<Boolean> specifies whether or not to draw an underline underneath -characters. -It may have any of the forms accepted by B<Tk_GetBoolean>. - -=item B<-wrap> =E<gt> I<mode> - -I<Mode> specifies how to handle lines that are wider than the -text's window. -It has the same legal values as the B<-wrap> option -for the text widget: B<none>, B<char>, or B<word>. -If this tag option is specified, it overrides the B<-wrap> option -for the text widget. - -=back - -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 -<perl/Tk callback|Tk::callbacks> 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 B<tagBind> widget -method below. - -The third use for tags is in managing the selection. -See L<"THE SELECTION"> below. - -=head1 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 ``I<$text>-E<gt>B<mark>'' text widget -method, and their current locations may be determined by using the -mark name as an index in methods. - -Each mark also has a I<gravity>, which is either B<left> or -B<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 B<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 B<insert> is associated with the insertion cursor, -as described under L<"THE INSERTION CURSOR"> below. -Second, the mark B<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: B<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. - -=head1 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 -B<widgetCreate> method, several configuration -options may be associated with it. -These options may be modified later with the B<widgetConfigure> -method. -The following options are currently supported: - -=over 4 - -=item B<-align> =E<gt> I<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. -I<Where> must have one of the values B<top> (align the top of the window -with the top of the line), B<center> (center the window -within the range of the line), B<bottom> (align the bottom of the -window with the bottom of the line's area), -or B<baseline> (align the bottom of the window with the baseline -of the line). - -=item B<-create> =E<gt> I<callback> - -Specifies a L<callback|Tk::callbacks> that may be evaluated to create the window -for the annotation. -If no B<-window> option has been specified for the annotation -this I<callback> will be evaluated when the annotation is about to -be displayed on the screen. -I<Callback> 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, I<callback> -will be evaluated again the next time the annotation is displayed. - -=item B<-padx> =E<gt> I<pixels> - -I<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 -(see B<Tk_GetPixels>). - -=item B<-pady> =E<gt> I<pixels> - -I<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 -(see B<Tk_GetPixels>). - -=item B<-stretch> =E<gt> I<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 B<-pady> option has been specified as well, then the -requested padding will be retained even if the window is -stretched. - -=item B<-window> =E<gt> I<$widget> - -Specifies the name of a window to display in the annotation. - -=back - -=head1 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 with B<imageCreate>. -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 B<image> -create method, 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 B<-name> option -(described below). If the B<-name> option is not provided, the -B<-image> name is used instead. If the I<imageName> is already -in use in the text widget, then B<#>I<nn> is added to the end of the -I<imageName>, where I<nn> is an arbitrary integer. This insures -the I<imageName> is unique. -Once this name is assigned to this instance of the image, it does not -change, even though the B<-image> or B<-name> values can be changed -with B<image configure>. - -When an embedded image is added to a text widget with the -B<imageCreate> method, several configuration -options may be associated with it. -These options may be modified later with the B<image configure> -method. -The following options are currently supported: - -=over 4 - -=item B<-align> =E<gt> I<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. -I<Where> must have one of the values B<top> (align the top of the image -with the top of the line), B<center> (center the image -within the range of the line), B<bottom> (align the bottom of the -image with the bottom of the line's area), -or B<baseline> (align the bottom of the image with the baseline -of the line). - -=item B<-image> =E<gt> I<image> - -Specifies the name of the Tk image to display in the annotation. -If I<image> is not a valid Tk image, then an error is returned. - -=item B<-name> =E<gt> I<ImageName> - -Specifies the name by which this image instance may be referenced in -the text widget. If I<ImageName> is not supplied, then the -name of the Tk image is used instead. -If the I<imageName> is already in use, I<#nn> is appended to -the end of the name as described above. - -=item B<-padx> =E<gt> I<pixels> - -I<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. - -=item B<-pady> =E<gt> I<pixels> - -I<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. - -=back - -=head1 THE SELECTION - -Selection support is implemented via tags. -If the B<exportSelection> option for the text widget is true -then the B<sel> tag will be associated with the selection: - -=over 4 - -=item [1] - -Whenever characters are tagged with B<sel> the text widget -will claim ownership of the selection. - -=item [2] - -Attempts to retrieve the -selection will be serviced by the text widget, returning all the -characters with the B<sel> tag. - -=item [3] - -If the selection is claimed away by another application or by another -window within this application, then the B<sel> tag will be removed -from all characters in the text. - -=item [4] - -Whenever the sel tag range changes a virtual event B<<<Selection>>> -is generated. - -The B<sel> tag is automatically defined when a text widget is -created, and it may not be deleted with the ``I<$text>-E<gt>B<tagDelete>'' -method. Furthermore, the B<selectBackground>, -B<selectBorderWidth>, and B<selectForeground> options for -the text widget are tied to the B<-background>, -B<-borderwidth>, and B<-foreground> options for the B<sel> -tag: changes in either will automatically be reflected in the -other. - -=back - -=head1 THE INSERTION CURSOR - -The mark named B<insert> has special significance in text widgets. -It is defined automatically when a text widget is created and it -may not be unset with the ``I<$text>-E<gt>B<markUnset>'' widget -command. -The B<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. - -=head1 THE MODIFIED FLAG - -The 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 programatically as well. -Whenever the flag changes state a B<<<Modified>>> virtual event is gener- -ated. See the edit modified widget command for more details. - - -=head1 WIDGET METHODS - -The B<Text> method creates a widget object. -This object supports the B<configure> and B<cget> methods -described in L<Tk::options> which can be used to enquire and -modify the options described above. -The widget also inherits all the methods provided by the generic -L<Tk::Widget|Tk::Widget> class. - -The following additional methods are available for text widgets. -In addition, the extended text widget methods as documented -in I<"Mastering Perl/Tk"> are included in this pod (with -permission from the publisher, B<O'Reilly and Associates Inc.>). - -=over 4 - -=item I<$text>-E<gt>B<adjustSelect> - -Moves the end point of the selection and anchor point to the -mouse pointer location. - -=item I<$text>-E<gt>B<bbox>(I<index>) - -Returns a list of four elements describing the screen area -of the character given by I<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. - -=item I<$text>-E<gt>B<clipboardColumnCopy> - -Performs a rectangular copy of the currently selected text with -basic compensation for tab characters. - -=item I<$text>-E<gt>B<clipboardColumnCut> - -Performs a rectangular cut of the currently selected text with -basic compensation for tab characters. - -=item I<$text>-E<gt>B<clipboardColumnPaste> - -Performs a rectangular paste of the text in the clipboard. The -upper-left corner is specified by the current position of the -insert mark with basic compensation for tab characters. - -=item I<$text>-E<gt>B<compare>(I<index1, op, index2>) - -Compares the indices given by I<index1> and I<index2> according -to the relational operator given by I<op>, and returns 1 if -the relationship is satisfied and 0 if it isn't. -I<Op> must be one of the operators E<lt>, E<lt>=, ==, E<gt>=, E<gt>, or !=. -If I<op> is == then 1 is returned if the two indices refer to -the same character, if I<op> is E<lt> then 1 is returned if I<index1> -refers to an earlier character in the text than I<index2>, and -so on. - -=item I<$text>-E<gt>B<Contents>(I<?args>?) - -Query or change the entire contents of the text widget. If no -arguments are given, the entire contents of the text widget are -returned. If any arguments are given, the entire contents of the -text widget are deleted and replaced by the argument list. - -=item I<$text>-E<gt>B<debug>(?I<boolean>?) - -If I<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 I<boolean> has a false value then the debugging checks will -be turned off. -In either case the command returns an empty string. -If I<boolean> is not specified then the command returns B<on> -or B<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. - -=item I<$text>-E<gt>B<delete>(I<index1, >?I<index2>?) - -Delete a range of characters from the text. -If both I<index1> and I<index2> are specified, then delete -all the characters starting with the one given by I<index1> -and stopping just before I<index2> (i.e. the character at -I<index2> is not deleted). -If I<index2> doesn't specify a position later in the text -than I<index1> then no characters are deleted. -If I<index2> isn't specified then the single character at -I<index1> is deleted. -It is not allowable to delete characters in a way that would leave -the text without a newline as the last character. -The command returns an empty string. -If more indices are given, multiple ranges of text will -be deleted. All indices are first checked for validity before -any deletions are made. They are sorted and the text is removed -from the last range to the first range to deleted text does not -cause a undesired index shifting side-effects. If multiple -ranges with the same start index are given, then the longest -range is used. If overlapping ranges are given, then they will -be merged into spans that do not cause deletion of text outside -the given ranges due to text shifted during deletion. - -=item I<$text>-E<gt>B<deleteSelected> - -Delete the currently selected text. - -=item I<$text>-E<gt>B<deleteTextTaggedWith>(I<tag>) - -Delete the text tagged with the I<tag> parameter. - -=item I<$text>-E<gt>B<deleteToEndofLine> - -Delete from the insert mark location to the end of line. - -=item I<$text>-E<gt>B<dlineinfo>(I<index>) - -Returns a list with five elements describing the area occupied -by the display line containing I<index>. -The first two elements of the list give the x and y coordinates -of the upper-left corner of the area occupied by the -line, the third and fourth elements give the width and height -of the area, and the fifth element gives the position of the baseline -for the line, measured down from the top of the area. -All of this information is measured in pixels. -If the current wrap mode is B<none> and the line extends beyond -the boundaries of the window, -the area returned reflects the entire area of the line, including the -portions that are out of the window. -If the line is shorter than the full width of the window then the -area returned reflects just the portion of the line that is occupied -by characters and embedded windows. -If the display line containing I<index> is not visible on -the screen then the return value is an empty list. - -=item I<$text>-E<gt>B<dump>(?I<switches>?, I<index1, >?I<index2>?) - -Return the contents of the text widget from I<index1> up to, -but not including I<index2>, -including the text and -information about marks, tags, and embedded windows. -If I<index2> is not specified, then it defaults to -one character past I<index1>. The information is returned -in the following format: - -I<key1 value1 index1 key2 value2 index2> ... - -The possible I<key> values are B<text>, B<mark>, -B<tagon>, B<tagoff>, and I<$text>. The corresponding -I<value> is the text, mark name, tag name, or window name. -The I<index> information is the index of the -start of the text, the mark, the tag transition, or the window. -One or more of the following switches (or abbreviations thereof) -may be specified to control the dump: - -=over 4 - -=item B<-all> - -Return information about all elements: text, marks, tags, and windows. -This is the default. - -=item B<-command> =E<gt> I<callback> - -Instead of returning the information as the result of the dump operation, -invoke the I<callback> on each element of the text widget within the range. -The callback has three arguments appended to it before it is evaluated: -the I<key>, I<value>, and I<index>. - -=item B<-mark> - -Include information about marks in the dump results. - -=item B<-tag> - -Include information about tag transitions in the dump results. Tag information is -returned as B<tagon> and B<tagoff> elements that indicate the -begin and end of each range of each tag, respectively. - -=item B<-text> - -Include information about text in the dump results. The value is the -text up to the next element or the end of range indicated by I<index2>. -A text element does not span newlines. A multi-line block of text that -contains no marks or tag transitions will still be dumped as a set -of text seqments that each end with a newline. The newline is part -of the value. - -=item B<-window> - -=back - -Include information about embedded windows in the dump results. -The value of a window is its Tk pathname, unless the window -has not been created yet. (It must have a create script.) -In this case an empty string is returned, and you must query the -window by its index position to get more information. - -=item I<$text>-E<gt>B<edit>( I< 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: - -=over 4 - -=item I<$text>-E<gt>B<editModified>( ?boolean? ); - -If boolean is not specified, returns the modified flag of -the widget. The insert, delete, edit undo and edit redo -commands or the user can set or clear the modified flag. -If boolean is specified, sets the modified flag of the -widget to boolean. - -=item I<$text>-E<gt>B<editRedo>; - -(Not implemented, use B<TextUndo>.) When the B<-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 B<-undo> option is false. - -=item I<$text>-E<gt>B<editReset>; - -(Not implemented, use B<TextUndo>.) Clears the undo and redo stacks. - -=item I<$text>-E<gt>B<editSeparator>; - -(Not implemented, use B<TextUndo>.) Inserts a separator (boundary) on -the undo stack. Does nothing when the -undo option is false. - -=item I<$text>-E<gt>B<editUndo>; - -(Not implemented, use B<TextUndo>.) Undoes the last edit action when -the -undo option is true. An edit action is defined as all the insert -and delete commands that are recorded on the undo stack in between two -separators. Generates an error when the undo stack is empty. Does -nothing when the -undo option is false. - -=back - -=item I<$text>-E<gt>B<FindAll>(I<mode, case, pattern>) - -Removes any current selections and then performs a global text -search. All matches are tagged with the B<sel> tag. - -I<mode> can be be B<-exact> or B<-regexp>. See the B<search> command -for more information - -I<case> can be B<-nocase> or B<-case>. See the B<search> command -for more information - -I<pattern> is an exact string to match if I<mode> is B<-exact> or a -regular expression if the match I<mode> is B<-regexp>. - - -=item I<$text>-E<gt>B<FindAndReplaceAll>(I<mode, case, find, replace>) - -Same as the B<FindAll> method, however additionally substitutes the -matched text with the characters I<replace>. - -=item I<$text>-E<gt>B<FindAndReplacePopUp> - -Creates a find-and-replace popup window if one does not already exist. -If there is currently selected text, then the 'find' field will be -'pre-filled' with the selection. - -=item I<$text>-E<gt>B<FindNext>(I<direction, mode, case, pattern>) - -Removes any current selections and then performs a forward or reverse -text search. All matches are tagged with the B<sel> tag. I<direction> -can be B<-forward> or B<-reverse>. I<mode, case> and I<pattern> are -as for the B<FindAll> method. - -=item I<$text>-E<gt>B<FindPopUp> - -Creates a find popup, if one does not yet exist. If there is currently -selected text, then the 'find' field will be 'pre-filled' with the -selection. - -=item I<$text>-E<gt>B<FindSelectionNext> - -Gets the currently selected text and removes all selections. It then -finds the next exact, case-sensitive string that matches in a forward -direction and selects the text and makes the new selection visible. - -=item I<$text>-E<gt>B<FindSelectionPrevious> - -Gets the currently selected text and removes all selections. It then -finds the next exact, case-sensitive string that matches in a reverse -direction and selects the text and makes the new selection visible. - -=item I<$text>-E<gt>B<get>(I<index1, >?I<index2>?) - -Return a range of characters from the text. The return value will be -all the characters in the text starting with the one whose index is -I<index1> and ending just before the one whose index is I<index2> (the -character at I<index2> will not be returned). If I<index2> is omitted -then the single character at I<index1> is returned. If there are no -characters in the specified range (e.g. I<index1> is past the end of -the file or I<index2> is less than or equal to I<index1>) then an -empty string is returned. If the specified range contains embedded -windows, no information about them is included in the returned string. -If multiple index pairs are given, multiple ranges of text will be -returned in a list. Invalid ranges will not be represented with empty -strings in the list. The ranges are returned in the order passed to -B<get>. - -=item I<$text>-E<gt>B<getSelected> - -Return the currently selected text. - -=item I<$text>-E<gt>B<GetTextTaggedWith>(I<tag>) - -Return the text tagged with the I<tag> parameter. - -=item I<$text>-E<gt>B<GotoLineNumber>(I<line_number>) - -Set the insert mark to I<line_number> and ensures the line is -visible. - -=item I<$text>-E<gt>B<GotoLineNumberPopUp>(I<line_number>) - -Displays a popup, pre-filling it with selected numeric text -(if any), or the line number from B<GotoLineNumber> (if any). - -=item I<$text>-E<gt>B<image>(I<option>, ?I<arg, arg, ...>?) - -=item I<$text>-E<gt>B<image>I<Option>(?I<arg, arg, ...>?) - -This method is used to manipulate embedded images. -The behavior of the method depends on the I<option> argument -that follows the B<image> prefix. -The following forms of the methods are currently supported: - -=over 8 - -=item I<$text>-E<gt>B<imageCget>(I<index, option>) - -Returns the value of a configuration option for an embedded image. -I<Index> identifies the embedded image, and I<option> -specifies a particular configuration option, which must be one of -the ones listed in L<"EMBEDDED IMAGES">. - -=item I<$text>-E<gt>B<imageConfigure>(I<index, >?I<option, value, ...>?) - -Query or modify the configuration options for an embedded image. -If no I<option> is specified, returns a list describing all of -the available options for the embedded image at I<index> -(see L<Tk::options> for information on the format of this list). -If I<option> is specified with no I<value>, then the command -returns a list describing the one named option (this list will be -identical to the corresponding sublist of the value returned if no -I<option> is specified). -If one or more I<option-value> pairs are specified, then the command -modifies the given option(s) to have the given value(s); in -this case the command returns an empty string. -See L<"EMBEDDED IMAGES"> for information on the options that -are supported. - -=item I<$text>-E<gt>B<imageCreate>(I<index, >?I<option, value, ...>?) - -This command creates a new image annotation, which will appear -in the text at the position given by I<index>. -Any number of I<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 L<"EMBEDDED IMAGES"> for information on the options that -are supported, and a description of the identifier returned. - -=item I<$text>-E<gt>B<imageNames> - -Returns a list whose elements are the names of all image instances currently -embedded in $text. - -=back - -=item I<$text>-E<gt>B<index>(I<index>) - -Returns the position corresponding to I<index> in the form -I<line.char> where I<line> is the line number and I<char> -is the character number. -I<Index> may have any of the forms described under L<"INDICES"> above. - -=item I<$text>-E<gt>B<insert>(I<index, chars, >?I<tagList, chars, tagList, ...>?) - -Inserts all of the I<chars> arguments just before the character at -I<index>. -If I<index> refers to the end of the text (the character after -the last newline) then the new text is inserted just before the -last newline instead. -If there is a single I<chars> argument and no I<tagList>, then -the new text will receive any tags that are present on both the -character before and the character after the insertion point; if a tag -is present on only one of these characters then it will not be -applied to the new text. -If I<tagList> is specified then it consists of a list of -tag names; the new characters will receive all of the tags in -this list and no others, regardless of the tags present around -the insertion point. -If multiple I<chars>-I<tagList> argument pairs are present, -they produce the same effect as if a separate B<insert> widget -command had been issued for each pair, in order. -The last I<tagList> argument may be omitted. - -=item I<$text>-E<gt>B<Insert>(I<string>) - -Do NOT confuse this with the lower-case B<insert> method. -Insert I<string> at the point of the insertion cursor. If there is -a selection in the text, and it covers the point of the insertion -cursor, then it deletes the selection before inserting. - -=item I<$text>-E<gt>B<InsertKeypress>(I<character>) - -Inserts I<character> at the B<insert> mark. If in overstrike mode, -it firsts deletes the character at the B<insert> mark. - -=item I<$text>-E<gt>B<InsertSelection> - -Inserts the current selection at the B<insert> mark. - -=item I<$text>-E<gt>B<insertTab> - -Inserts a tab (\t) character at the B<insert> mark. - -=item I<$text>-E<gt>B<mark>(I<option, >?I<arg, arg, ...>?) - -This command is used to manipulate marks. The exact behavior of -the command depends on the I<option> argument that follows -the B<mark> argument. The following forms of the command -are currently supported: - -=over 8 - -=item I<$text>-E<gt>B<markGravity>(I<markName, >?I<direction>?) - -If I<direction> is not specified, returns B<left> or B<right> -to indicate which of its adjacent characters I<markName> is attached -to. -If I<direction> is specified, it must be B<left> or B<right>; -the gravity of I<markName> is set to the given value. - -=item I<$text>-E<gt>B<markNames> - -Returns a list whose elements are the names of all the marks that -are currently set. - -=item I<$text>-E<gt>B<markNext>(I<index>) - -Returns the name of the next mark at or after I<index>. -If I<index> is specified in numerical form, then the search for -the next mark begins at that index. -If I<index> is the name of a mark, then the search for -the next mark begins immediately after that mark. -This can still return a mark at the same position if -there are multiple marks at the same index. -These semantics mean that the B<mark next> operation can be used to -step through all the marks in a text widget in the same order -as the mark information returned by the B<dump> operation. -If a mark has been set to the special B<end> index, -then it appears to be I<after> B<end> with respect to the B<mark next> operation. -An empty string is returned if there are no marks after I<index>. - -=item I<$text>-E<gt>B<markPrevious>(I<index>) - -Returns the name of the mark at or before I<index>. -If I<index> is specified in numerical form, then the search for -the previous mark begins with the character just before that index. -If I<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 B<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 B<dump> operation. -An empty string is returned if there are no marks before I<index>. - -=item I<$text>-E<gt>B<markSet>(I<markName, index>) - -Sets the mark named I<markName> to a position just before the -character at I<index>. -If I<markName> already exists, it is moved from its old position; -if it doesn't exist, a new mark is created. -This command returns an empty string. - -=item I<$text>-E<gt>B<markUnset>(I<markName>?, I<markName, markName, ...>?) - -Remove the mark corresponding to each of the I<markName> arguments. -The removed marks will not be usable in indices and will not be -returned by future calls to ``I<$text>-E<gt>B<markNames>''. -This command returns an empty string. - -=back - -=item I<$text>-E<gt>B<markExists>(I<markname>) - -Returns true if I<markname> exists - false otherwise. - -=item I<$text>-E<gt>B<menu>(I<?menu?>) - -If I<menu> reference is given as an argument, then the text widget -menu is adjusted to use this new I<menu>. If the I<menu> argument -is B<undef>, then this command disables the current text widget menu. -If the I<menu> argument is omitted altogether, then the current text -widget menu reference is returned. - -=item I<$text>-E<gt>B<openLine> - -Inserts a newline (\n) at the insert mark. - -=item I<$text>-E<gt>B<OverstrikeMode>(I<?boolean?>) - -Returns the overstrike mode if I<boolean> is omitted or sets the -overstrike mode to I<boolean>. True means overstrike mode is enabled. - -=item I<$text>-E<gt>B<PostPopupMenu>(I<x,y>) - -Creates a popup menu at the specified (I<x,y>) pixel coordinates. The -default menu has File, Edit, Search and View menu items which cascade -to sub-menus for further commands. There is an implicit E<lt>Button-3E<gt> -binding to this method that posts the menu over the cursor. - -=item I<$text>-E<gt>B<ResetAnchor> - -Sets the selection anchor to whichever end is farthest from the index -argument. - -=item I<$text>-E<gt>B<scan>(I<option>, I<args>) or - -=item I<$text>-E<gt>B<scan>I<option>(I<args>) - -This method is used to implement scanning on texts. It has -two forms, depending on I<option>: - -=over 8 - -=item I<$text>-E<gt>B<scanMark>(I<x, y>) - -Records I<x> and I<y> and the current view in the text window, -for use in conjunction with later B<scanDragto> method. -Typically this method is associated with a mouse button press in -the widget. It returns an empty string. - -=item I<$text>-E<gt>B<scanDragto>(I<x, y>) - -This command computes the difference between its I<x> and I<y> -arguments and the I<x> and I<y> arguments to the last -B<scanMark> method for the widget. -It then adjusts the view by 10 times the difference in coordinates. -This command is typically associated -with mouse motion events in the widget, to produce the effect of -dragging the text at high speed through the window. The return -value is an empty string. - -=back - -=item I<$text>-E<gt>B<search>(?I<switches>,? I<pattern, index, >?I<stopIndex>?) - -Searches the text in I<$text> starting at I<index> for a range -of characters that matches I<pattern>. -If a match is found, the index of the first character in the match is -returned as result; otherwise an empty string is returned. -One or more of the following switches (or abbreviations thereof) -may be specified to control the search: - -=over 8 - -=item B<-forwards> - -The search will proceed forward through the text, finding the first -matching range starting at or after the position given by I<index>. -This is the default. - -=item B<-backwards> - -The search will proceed backward through the text, finding the -matching range closest to I<index> whose first character -is before I<index>. - -=item B<-exact> - -Use exact matching: the characters in the matching range must be -identical to those in I<pattern>. -This is the default. - -=item B<-regexp> - -Treat I<pattern> as a regular expression and match it against -the text using the rules for regular expressions (see the B<regexp> -command for details). - -=item B<-nocase> - -Ignore case differences between the pattern and the text. - -=item B<-count>I< varName> - -The argument following B<-count> gives the name of a variable; -if a match is found, the number of characters in the matching -range will be stored in the variable. - -=item B<-hidden> - -Find hidden text as well. By default only displayed text is found. - -=item B<--> - -This switch has no effect except to terminate the list of switches: -the next argument will be treated as I<pattern> even if it starts -with B<->. - -=back - -=back - -The matching range must be entirely within a single line of text. -For regular expression matching the newlines are removed from the ends -of the lines before matching: use the B<$> feature in regular -expressions to match the end of a line. -For exact matching the newlines are retained. -If I<stopIndex> is specified, the search stops at that index: -for forward searches, no match at or after I<stopIndex> will -be considered; for backward searches, no match earlier in the -text than I<stopIndex> will be considered. -If I<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 I<stopIndex> is specified, no wrap-around will occur. - -=over 4 - -=item I<$text>-E<gt>B<see>(I<index>) - -Adjusts the view in the window so that the character given by I<index> -is completely visible. -If I<index> is already visible then the command does nothing. -If I<index> is a short distance out of view, the command -adjusts the view just enough to make I<index> visible at the -edge of the window. -If I<index> is far out of view, then the command centers -I<index> in the window. - -=item I<$text>-E<gt>B<selectAll> - -Selects all the text in the widget. - -=item I<$text>-E<gt>B<selectLine> - -Selects the line with the insert mark. - -=item I<$text>-E<gt>B<selectWord> - -Selects the word with the insert mark. - -=item I<$text>-E<gt>B<SetCursor>(I<position>) - -Moves the insert mark to I<position>. - -=item I<$text>-E<gt>B<tag>(I<option, >?I<arg, arg, ...>?) - -This command is used to manipulate tags. The exact behavior of the -command depends on the I<option> argument that follows the -B<tag> argument. The following forms of the command are currently -supported: - -=over 8 - -=item I<$text>-E<gt>B<tagAdd>(I<tagName, index1, >?I<index2, index1, index2, ...>?) - -Associate the tag I<tagName> with all of the characters starting -with I<index1> and ending just before -I<index2> (the character at I<index2> isn't tagged). -A single command may contain any number of I<index1>-I<index2> -pairs. -If the last I<index2> is omitted then the single character at -I<index1> is tagged. -If there are no characters in the specified range (e.g. I<index1> -is past the end of the file or I<index2> is less than or equal -to I<index1>) then the command has no effect. - -=item I<$text>-E<gt>B<tagBind>(I<tagName, >?I<sequence>?, ?I<script>?) - -This command associates I<script> with the tag given by -I<tagName>. -Whenever the event sequence given by I<sequence> occurs for a -character that has been tagged with I<tagName>, -the script will be invoked. -This method is similar to the B<bind> command except that -it operates on characters in a text rather than entire widgets. -See the L<Tk::bind> documentation for complete details -on the syntax of I<sequence> and the substitutions performed -on I<script> before invoking it. -If all arguments are specified then a new binding is created, replacing -any existing binding for the same I<sequence> and I<tagName> -(if the first character of I<script> is ``+'' then I<script> -augments an existing binding rather than replacing it). -In this case the return value is an empty string. -If I<script> is omitted then the command returns the I<script> -associated with I<tagName> and I<sequence> (an error occurs -if there is no such binding). -If both I<script> and I<sequence> are omitted then the command -returns a list of all the sequences for which bindings have been -defined for I<tagName>. - -The only events for which bindings may be specified are those related -to the mouse and keyboard (such as B<Enter>, B<Leave>, -B<ButtonPress>, B<Motion>, and B<KeyPress>) or virtual events. -Event bindings for a text widget use the B<current> mark described -under L<"MARKS"> above. An B<Enter> event triggers for a tag when the tag -first becomes present on the current character, and a B<Leave> event -triggers for a tag when it ceases to be present on the current character. -B<Enter> and B<Leave> events can happen either because the -B<current> mark moved or because the character at that position -changed. Note that these events are different than B<Enter> and -B<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 the documentation for -the B<bind> command for details). -B<continue> and B<break> commands within binding scripts -are processed in the same way as for bindings created with -the B<bind> command. - -If bindings are created for the widget as a whole using the -B<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. - -=item I<$text>-E<gt>B<tagCget>(I<tagName, option>) - -This command returns the current value of the option named I<option> -associated with the tag given by I<tagName>. -I<Option> may have any of the values accepted by the B<tag configure> -method. - -=item I<$text>-E<gt>B<tagConfigure>(I<tagName, >?I<option>?, ?I<value>?, ?I<option, value, ...>?) - -This command is similar to the B<configure> method except -that it modifies options associated with the tag given by I<tagName> -instead of modifying options for the overall text widget. -If no I<option> is specified, the command returns a list describing -all of the available options for I<tagName> -(see L<Tk::options> for information on the format of this list). -If I<option> is specified with no I<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 I<option> -is specified). -If one or more I<option-value> pairs are specified, then the command -modifies the given option(s) to have the given value(s) in I<tagName>; -in this case the command returns an empty string. -See L<"TAGS"> above for details on the options available for tags. - -=item I<$text>-E<gt>B<tagDelete>(I<tagName, >?I<tagName, ...>?) - -Deletes all tag information for each of the I<tagName> -arguments. -The command removes the tags from all characters in the file -and also deletes any other information associated with the tags, -such as bindings and display information. -The command returns an empty string. - -=item I<$text>-E<gt>B<tagLower>(I<tagName>?, I<belowThis>?) - -Changes the priority of tag I<tagName> so that it is just lower -in priority than the tag whose name is I<belowThis>. -If I<belowThis> is omitted, then I<tagName>'s priority -is changed to make it lowest priority of all tags. - -=item I<$text>-E<gt>B<tagNames>(?I<index>?) - -Returns a list whose elements are the names of all the tags that -are active at the character position given by I<index>. -If I<index> is omitted, then the return value will describe -all of the tags that exist for the text (this includes all tags -that have been named in a ``I<$text>-E<gt>B<tag>'' widget -command but haven't been deleted by a ``I<$text>-E<gt>B<tagDelete>'' -method, even if no characters are currently marked with -the tag). -The list will be sorted in order from lowest priority to highest -priority. - -=item I<$text>-E<gt>B<tagNextrange>(I<tagName, index1, >?I<index2>?) - -This command searches the text for a range of characters tagged -with I<tagName> where the first character of the range is -no earlier than the character at I<index1> and no later than -the character just before I<index2> (a range starting at -I<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 I<index2> is not given then it defaults to the end of the text. - -=item I<$text>-E<gt>B<tagPrevrange>(I<tagName, index1, >?I<index2>?) - -This command searches the text for a range of characters tagged -with I<tagName> where the first character of the range is -before the character at I<index1> and no earlier than -the character at I<index2> (a range starting at -I<index2> will be considered). -If several matching ranges exist, the one closest to I<index1> is chosen. -The command's return value is a list containing -two elements, which are the index of the first character of the -range and the index of the character just after the last one in -the range. -If no matching range is found then the return value is an -empty string. -If I<index2> is not given then it defaults to the beginning of the text. - -=item I<$text>-E<gt>B<tagRaise>(I<tagName, >?I<aboveThis>?) - -Changes the priority of tag I<tagName> so that it is just higher -in priority than the tag whose name is I<aboveThis>. -If I<aboveThis> is omitted, then I<tagName>'s priority -is changed to make it highest priority of all tags. - -=item I<$text>-E<gt>B<tagRanges>(I<tagName>) - -Returns a list describing all of the ranges of text that have been -tagged with I<tagName>. -The first two elements of the list describe the first tagged range -in the text, the next two elements describe the second range, and -so on. -The first element of each pair contains the index of the first -character of the range, and the second element of the pair contains -the index of the character just after the last one in the -range. -If there are no characters tagged with I<tag> then an -empty string is returned. - -=item I<$text>-E<gt>B<tagRemove>(I<tagName, index1, >?I<index2, index1, index2, ...>?) - -Remove the tag I<tagName> from all of the characters starting -at I<index1> and ending just before -I<index2> (the character at I<index2> isn't affected). -A single command may contain any number of I<index1>-I<index2> -pairs. -If the last I<index2> is omitted then the single character at -I<index1> is tagged. -If there are no characters in the specified range (e.g. I<index1> -is past the end of the file or I<index2> is less than or equal -to I<index1>) then the command has no effect. -This command returns an empty string. - -=back - -=item I<$text>-E<gt>B<ToggleInsertMode> - -Toggles the current overstrike mode. - -=item I<$text>-E<gt>B<unselectAll> - -Unselects all the text in the widget. - -=item I<$text>-E<gt>B<WhatLineNumberPopup> - -Creates a popup that displays the current line number of the -insert mark. - -=item I<$text>->B<widget>(I<option?, arg, arg, ...>?) - -=item I<$text>->B<widget>I<Option>(?I<arg, arg, ...>?) - -This method is used to manipulate embedded windows. -The behavior of the method depends on the I<option> argument -that follows the B<window> argument. -The following forms of the method are currently supported: - -=over 8 - -=item I<$text>->B<windowCget>(I<index, option>) - -Returns the value of a configuration option for an embedded window. -I<Index> identifies the embedded window, and I<option> -specifies a particular configuration option, which must be one of -the ones listed in L<"EMBEDDED WINDOWS"> above. - -=item I<$text>->B<windowConfigure>(I<index>?, I<option, value, ...>?) - -Query or modify the configuration options for an embedded window. -If no I<option> is specified, returns a list describing all of -the available options for the embedded window at I<index> -(see L<Tk::options> for information on the format of this list). -If I<option> is specified with no I<value>, then the command -returns a list describing the one named option (this list will be -identical to the corresponding sublist of the value returned if no -I<option> is specified). -If one or more I<option-value> pairs are specified, then the command -modifies the given option(s) to have the given value(s); in -this case the command returns an empty string. -See L<"EMBEDDED WINDOWS"> above for information on the options that -are supported. - -=item I<$text>->B<windowCreate>(I<index>?, I<option, value, ...>?) - -This command creates a new window annotation, which will appear -in the text at the position given by I<index>. -Any number of I<option-value> pairs may be specified to -configure the annotation. -See L<"EMBEDDED WINDOWS"> above for information on the options that -are supported. -Returns an empty string. - -=item I<$text>->B<windowNames> - -Returns a list whose elements are the names of all windows currently -embedded in $text. - -=back - -=item I<$text>->B<xview>(I<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: - -=over 8 - -=item I<$text>->B<xview> - -Returns a list containing two elements. -Each element is a real fraction between 0 and 1; together they describe -the portion of the document's horizontal span that is visible in -the window. -For example, if the first element is .2 and the second element is .6, -20% of the text is off-screen to the left, the middle 40% is visible -in the window, and 40% of the text is off-screen to the right. -The fractions refer only to the lines that are actually visible in the -window: if the lines in the window are all very short, so that they -are entirely visible, the returned fractions will be 0 and 1, -even if there are other lines in the text that are -much wider than the window. -These are the same values passed to scrollbars via the B<-xscrollcommand> -option. - -=item I<$text>-E<gt>B<xviewMoveto>(I<fraction>) - -Adjusts the view in the window so that I<fraction> of the horizontal -span of the text is off-screen to the left. -I<Fraction> is a fraction between 0 and 1. - -=item I<$text>-E<gt>B<xviewScroll>(I<number, what>) - -This command shifts the view in the window left or right according to -I<number> and I<what>. -I<Number> must be an integer. -I<What> must be either B<units> or B<pages> or an abbreviation -of one of these. -If I<what> is B<units>, the view adjusts left or right by -I<number> average-width characters on the display; if it is -B<pages> then the view adjusts by I<number> screenfuls. -If I<number> is negative then characters farther to the left -become visible; if it is positive then characters farther to the right -become visible. - -=back - -=item I<$text>-E<gt>B<yview>(I<?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: - -=over 8 - -=item I<$text>-E<gt>B<yview> - -Returns a list containing two elements, both of which are real fractions -between 0 and 1. -The first element gives the position of the first character in the -top line in the window, relative to the text as a whole (0.5 means -it is halfway through the text, for example). -The second element gives the position of the character just after -the last one in the bottom line of the window, -relative to the text as a whole. -These are the same values passed to scrollbars via the B<-yscrollcommand> -option. - -=item I<$text>-E<gt>B<yviewMoveto>(I<fraction>) - -Adjusts the view in the window so that the character given by I<fraction> -appears on the top line of the window. -I<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. - -=item I<$text>-E<gt>B<yviewScroll>(I<number, what>) - -This command adjust the view in the window up or down according to -I<number> and I<what>. -I<Number> must be an integer. -I<What> must be either B<units> or B<pages>. -If I<what> is B<units>, the view adjusts up or down by -I<number> lines on the display; if it is B<pages> then -the view adjusts by I<number> screenfuls. -If I<number> is negative then earlier positions in the text -become visible; if it is positive then later positions in the text -become visible. - -=item I<$text>->B<yview>(?B<-pickplace>,? I<index>) - -Changes the view in the I<$text>'s window to make I<index> visible. -If the B<-pickplace> option isn't specified then I<index> will -appear at the top of the window. -If B<-pickplace> is specified then the widget chooses where -I<index> appears in the window: - -=over 12 - -=item [1] - -If I<index> is already visible somewhere in the window then the -command does nothing. - -=item [2] - -If I<index> is only a few lines off-screen above the window then -it will be positioned at the top of the window. - -=item [3] - -If I<index> is only a few lines off-screen below the window then -it will be positioned at the bottom of the window. - -=item [4] - -Otherwise, I<index> will be centered in the window. - -=back - -=back - -=back - -The B<-pickplace> option has been obsoleted by the B<see> widget -command (B<see> handles both x- and y-motion to make a location -visible, whereas B<-pickplace> only handles motion in y). - -=over 4 - -=item I<$text>-E<gt>B<yview>(I<number>) - -This command makes the first character on the line after -the one given by I<number> visible at the top of the window. -I<Number> must be an integer. -This command used to be used for scrolling, but now it is obsolete. - -=back - -=head1 BINDINGS - -Tk automatically creates class bindings for texts that give them -the following default behavior. -In the descriptions below, ``word'' refers to a contiguous group -of letters, digits, or ``_'' characters, or any single character -other than these. - -=over 4 - -=item [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. - -=item [2] - -Double-clicking with mouse button 1 selects the word under the mouse -and positions the insertion cursor at the beginning of the word. -Dragging after a double click will stroke out a selection consisting -of whole words. - -=item [3] - -Triple-clicking with mouse button 1 selects the line under the mouse -and positions the insertion cursor at the beginning of the line. -Dragging after a triple click will stroke out a selection consisting -of whole lines. - -=item [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. - -=item [5] - -Clicking mouse button 1 with the Control key down will reposition the -insertion cursor without affecting the selection. - -=item [6] - -If any normal printing characters are typed, they are -inserted at the point of the insertion cursor. - -=item [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. - -=item [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). - -=item [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. - -=item [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. - -=item [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. - -=item [12] - -Control-Next and Control-Prior scroll the view right or left by one page -without moving the insertion cursor or affecting the selection. - -=item [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. - -=item [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. - -=item [15] - -Control-Home and Meta-E<lt> 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. - -=item [16] - -Control-End and Meta-E<gt> 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. - -=item [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. - -=item [18] - -Control-/ selects the entire contents of the widget. - -=item [19] - -Control-\ clears any selection in the widget. - -=item [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. - -=item [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. -If there is no selection in the widget then these keys have no effect. - -=item [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. - -=item [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. - -=item [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. - -=item [25] - -Control-d deletes the character to the right of the insertion cursor. - -=item [26] - -Meta-d deletes the word to the right of the insertion cursor. - -=item [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. - -=item [28] - -Control-o opens a new line by inserting a newline character in -front of the insertion cursor without moving the insertion cursor. - -=item [29] - -Meta-backspace and Meta-Delete delete the word to the left of the -insertion cursor. - -=item [30] - -Control-x deletes whatever is selected in the text widget. - -=item [31] - -Control-t reverses the order of the two characters to the right of -the insertion cursor. - -=item [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. - -=item [33] - -Control-Z (or Control-y on Windows) reapplies the last undone edit -action if the -undo option is true. Does nothing otherwise. - -=back - -If the widget is disabled using the B<-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. - - -=head1 TIED INTERFACE - -The Perl/Tk Text widget also has built-in TIEHANDLE methods for -B<print> and B<printf> statements. This means you can print to file -handles tied to a Text widget, and the tied methods automatically -insert the print statement's arguments into the Text widget. - -For example: - - #!/usr/local/bin/perl -w - use POSIX 'acos'; - use Tk; - use strict; - - my $mw = MainWindow->new; - my $text = $mw->Text(qw/-width 40 -height 10/)->pack; - - tie *STDOUT, ref $text, $text; - - print "Hello Text World!\n"; - printf "pi ~= %1.5f", acos(-1.0); - - MainLoop; - - -=head1 PERFORMANCE ISSUES - -Text 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 B<-insertofftime> option to 0 avoid this. - -=head1 SEE ALSO - -L<Tk::ROText|Tk::ROText> -L<Tk::TextUndo|Tk::TextUndo> - -=head1 KEYWORDS - -text, widget - -=cut - - |