message(n) Tk (4.0) message(n)
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NAME
message - Create and manipulate message widgets
SYNOPSIS
message pathName ?options?
STANDARD OPTIONS
-anchor-font-highlightthickness-takefocus
-background-foreground-padx-text
-borderwidth-highlightbackground-pady-textvariable
-cursor-highlightcolor-relief-width
See the options manual entry for details on the standard
options.
WIDGET-SPECIFIC OPTIONS
Command-Line Name:-aspect
Database Name: aspect
Database Class: Aspect
Specifies a non-negative integer value indicating
desired aspect ratio for the text. The aspect ratio is
specified as 100*width/height. 100 means the text
should be as wide as it is tall, 200 means the text
should be twice as wide as it is tall, 50 means the
text should be twice as tall as it is wide, and so on.
Used to choose line length for text if width option
isn't specified. Defaults to 150.
Command-Line Name:-justify
Database Name: justify
Database Class: Justify
Specifies how to justify lines of text. Must be one of
left, center, or right. Defaults to left. This option
works together with the anchor, aspect, padX, padY, and
width options to provide a variety of arrangements of
the text within the window. The aspect and width
options determine the amount of screen space needed to
display the text. The anchor, padX, and padY options
determine where this rectangular area is displayed
within the widget's window, and the justify option
determines how each line is displayed within that
rectangular region. For example, suppose anchor is e
and justify is left, and that the message window is
much larger than needed for the text. The the text
will displayed so that the left edges of all the lines
line up and the right edge of the longest line is padX
from the right side of the window; the entire text
block will be centered in the vertical span of the
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message(n) Tk (4.0) message(n)
window.
Command-Line Name:-width
Database Name: width
Database Class: Width
Specifies the length of lines in the window. The value
may have any of the forms acceptable to Tk_GetPixels.
If this option has a value greater than zero then the
aspect option is ignored and the width option
determines the line length. If this option has a value
less than or equal to zero, then the aspect option
determines the line length.
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DESCRIPTION
The message command creates a new window (given by the
pathName argument) and makes it into a message widget.
Additional options, described above, may be specified on the
command line or in the option database to configure aspects
of the message such as its colors, font, text, and initial
relief. The message command returns its pathName argument.
At the time this command is invoked, there must not exist a
window named pathName, but pathName's parent must exist.
A message is a widget that displays a textual string. A
message widget has three special features. First, it breaks
up its string into lines in order to produce a given aspect
ratio for the window. The line breaks are chosen at word
boundaries wherever possible (if not even a single word
would fit on a line, then the word will be split across
lines). Newline characters in the string will force line
breaks; they can be used, for example, to leave blank lines
in the display.
The second feature of a message widget is justification.
The text may be displayed left-justified (each line starts
at the left side of the window), centered on a line-by-line
basis, or right-justified (each line ends at the right side
of the window).
The third feature of a message widget is that it handles
control characters and non-printing characters specially.
Tab characters are replaced with enough blank space to line
up on the next 8-character boundary. Newlines cause line
breaks. Other control characters (ASCII code less than
0x20) and characters not defined in the font are displayed
as a four-character sequence \xhh where hh is the two-digit
hexadecimal number corresponding to the character. In the
unusual case where the font doesn't contain all of the
characters in ``0123456789abcdef\x'' then control characters
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message(n) Tk (4.0) message(n)
and undefined characters are not displayed at all.
WIDGET COMMAND
The message command creates a new Tcl command whose name is
pathName. This command may be used to invoke various
operations on the widget. It has the following general
form:
pathName option ?arg arg ...?
Option and the args determine the exact behavior of the
command. The following commands are possible for message
widgets:
pathName cget option
Returns the current value of the configuration option
given by option. Option may have any of the values
accepted by the message command.
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 message
command.
DEFAULT BINDINGS
When a new message is created, it has no default event
bindings: messages are intended for output purposes only.
BUGS
Tabs don't work very well with text that is centered or
right-justified. The most common result is that the line is
justified wrong.
KEYWORDS
message, widget
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