Section: User Contributed Perl Documentation (3)
Tk::Message - Create and manipulate Message widgets
-anchor -font -highlightthickness -takefocus
-background -foreground -padx -text
-borderwidth -highlightbackground -pady -textvariable
-cursor -highlightcolor -relief -width
See Tk::options for details of the standard options.
- Name: aspect
- Class: Aspect
- Switch: -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
Defaults to 150.
- Name: justify
- Class: Justify
- Switch: -justify
Specifies how to justify lines of text.
Must be one of left, center, or right. Defaults
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
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 window.
- Name: width
- Class: Width
- Switch: -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
If this option has a value less than or equal to zero, then
the aspect option determines the line length.
method creates a new window (given by the
argument) and makes it into a message widget.
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
argument. At the time this command is invoked,
there must not exist a window named $widget
'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 and undefined characters are not displayed at all.
method creates a widget object.
This object supports the configure
described in 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
When a new message is created, it has no default event bindings:
messages are intended for output purposes only.
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.