1message(n) Tk Built-In Commands message(n)
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8 message - Create and manipulate message widgets
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11 message pathName ?options?
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14 -anchor -highlightbackground -takefocus
15 -background -highlightcolor -text
16 -borderwidth -highlightthickness -textvariable
17 -cursor -padx -width
18 -font -pady
19 -foreground -relief
20 See the options manual entry for details on the standard options.
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24 [-aspect aspect] Specifies a non-negative integer value indicating
25 desired aspect ratio for the text. The aspect ratio is specified as
26 100*width/height. 100 means the text should be as wide as it is tall,
27 200 means the text should be twice as wide as it is tall, 50 means the
28 text should be twice as tall as it is wide, and so on. Used to choose
29 line length for text if width option isn't specified. Defaults to 150.
30 [-justify justify] Specifies how to justify lines of text. Must be one
31 of left, center, or right. Defaults to left. This option works
32 together with the anchor, aspect, padX, padY, and width options to pro‐
33 vide a variety of arrangements of the text within the window. The
34 aspect and width options determine the amount of screen space needed to
35 display the text. The anchor, padX, and padY options determine where
36 this rectangular area is displayed within the widget's window, and the
37 justify option determines how each line is displayed within that rec‐
38 tangular region. For example, suppose anchor is e and justify is left,
39 and that the message window is much larger than needed for the text.
40 The text will be displayed so that the left edges of all the lines line
41 up and the right edge of the longest line is padX from the right side
42 of the window; the entire text block will be centered in the vertical
43 span of the window. [-width width] Specifies the length of lines in
44 the window. The value may have any of the forms acceptable to Tk_Get‐
45 Pixels. If this option has a value greater than zero then the aspect
46 option is ignored and the width option determines the line length. If
47 this option has a value less than or equal to zero, then the aspect
48 option determines the line length.
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53 The message command creates a new window (given by the pathName argu‐
54 ment) and makes it into a message widget. Additional options,
55 described above, may be specified on the command line or in the option
56 database to configure aspects of the message such as its colors, font,
57 text, and initial relief. The message command returns its pathName
58 argument. At the time this command is invoked, there must not exist a
59 window named pathName, but pathName's parent must exist.
60 A message is a widget that displays a textual string. A message widget
62 has three special features. First, it breaks up its string into lines
63 in order to produce a given aspect ratio for the window. The line
64 breaks are chosen at word boundaries wherever possible (if not even a
65 single word would fit on a line, then the word will be split across
66 lines). Newline characters in the string will force line breaks; they
67 can be used, for example, to leave blank lines in the display.
68 The second feature of a message widget is justification. The text may
70 be displayed left-justified (each line starts at the left side of the
71 window), centered on a line-by-line basis, or right-justified (each
72 line ends at the right side of the window).
73 The third feature of a message widget is that it handles control char‐
75 acters and non-printing characters specially. Tab characters are
76 replaced with enough blank space to line up on the next 8-character
77 boundary. Newlines cause line breaks. Other control characters (ASCII
78 code less than 0x20) and characters not defined in the font are dis‐
79 played as a four-character sequence \xhh where hh is the two-digit
80 hexadecimal number corresponding to the character. In the unusual case
81 where the font doesn't contain all of the characters in
82 ``0123456789abcdef\x'' then control characters and undefined characters
83 are not displayed at all.
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87 The message command creates a new Tcl command whose name is pathName.
88 This command may be used to invoke various operations on the widget.
89 It has the following general form:
90 pathName option ?arg arg ...?
91 Option and the args determine the exact behavior of the command. The
92 following commands are possible for message widgets:
93 pathName cget option
95 Returns the current value of the configuration option given by
96 option. Option may have any of the values accepted by the mes‐
97 sage command.
98 pathName configure ?option? ?value option value ...?
100 Query or modify the configuration options of the widget. If no
101 option is specified, returns a list describing all of the avail‐
102 able options for pathName (see Tk_ConfigureInfo for information
103 on the format of this list). If option is specified with no
104 value, then the command returns a list describing the one named
105 option (this list will be identical to the corresponding sublist
106 of the value returned if no option is specified). If one or
107 more option-value pairs are specified, then the command modifies
108 the given widget option(s) to have the given value(s); in this
109 case the command returns an empty string. Option may have any
110 of the values accepted by the message command.
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114 When a new message is created, it has no default event bindings: mes‐
115 sages are intended for output purposes only.
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119 Tabs don't work very well with text that is centered or right-justi‐
120 fied. The most common result is that the line is justified wrong.
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124 message, widget
125Tk 4.0 message(n)