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8.2. Text Widget Options

Options used with the Text method change the way the text is displayed within the Text widget. The following options are standard for all the widgets (see Chapter 4, " Button, Checkbutton, and Radiobutton Widgets", where the options were first covered, for further information):

-background => color
Changes the color of the screen displayed behind the text.

-borderwidth => amount
Sets the width of the edges of the widget.

-cursor => cursorname
Sets the cursor displayed when the mouse cursor is in front of the Text widget.

-exportselection => 0 | 1
Determines if the text selected within the widget can also be used by the windowing system (such as X windows).

-font => fontname
Sets the font in which the text is displayed.

-foreground => color
Sets the color of the text.

-height => amount
Sets the height of the widget. Default is 24.

-highlightbackground => color
Sets the color the highlight rectangle around the widget should be when it does not have the keyboard focus.

-highlightcolor => color
Sets the color the highlight rectangle around the widget should be when it has the keyboard focus.

-highlightthickness => amount
Sets the thickness of the highlight rectangle around the widget. Default is 2.

-insertbackground => color
Changes the color of the insert cursor.

-insertborderwidth => amount
Changes the width of the insert cursor.

-insertofftime => time
Sets the time the insert cursor blinks in the off position. Default is 300.

-insertontime => time
Sets the time the insert cursor blinks in the on position. Default is 600.

-insertwidth => amount
Sets the width of the insert cursor.

-padx => amount
Adds extra space to the left and right of the text inside the Text widget's edge.

-pady => amount
Adds extra space to the top and bottom of the text inside the Text widget's edge.

-relief => 'flat'|'groove'|'raised'|'ridge'|'sunken'|'solid'
Sets the relief of the edges of the widget.

-selectbackground => color
Sets the color of the area behind the selected text.

-selectborderwidth => amount
Sets the width of the border of the selected area.

-selectforeground => color
Sets the color of the selected text.

-setgrid => 0 | 1
Enables gridding for the Text widget. Default is 0.

-spacing1 => amount
Sets the amount of additional space left on top of a line of text that begins on its own line. Default is 0.

-spacing2 => amount
Sets the amount of additional space left on top of a line of text after it has been wrapped around automatically by the Text widget. Default is 0.

-spacing3 => amount
Sets the amount of additional space left after a line of text has been ended by a "\n". Default is 0.

-state => 'normal' | 'disabled'
Indicates the state of the Text widget. If set to 'disabled', no text can be inserted by either the user or the application (via the insert method).

-tabs => list
Specifies a list of tab stops to use in the Text widget. Default is every eight characters.

-takefocus => 0 | 1 | undef
Determines if widget can obtain keyboard focus.

-width => amount
Sets the width of the Text widget in characters. Default is 80.

-wrap => 'none' | 'char' | 'word'
Sets the mode used to determine automatic line wrapping.

-xscrollcommand => callback
Determines the callback used when the Text widget is scrolled horizontally.

-yscrollcommand => callback
Determines the callback used when the Text widget is scrolled vertically.

8.2.1. Fonts

You can use the -font option to change the font, including how large or small the text is (see Figure 8-1). This defines the default font for the entire Text widget. Text that is inserted without a text tag (which allows you to specify formatting that applies only to certain portions of the text) will use this font.

Figure 8-1

Figure 8-1. Text widget using -font => "r16"

The use of fonts was covered in Chapter 3, "Fonts", where we first discussed the -font option.

8.2.3. Widget Style

As with other widgets, you can change how the edges of the Text widget are drawn using the -relief and -borderwidth options. The examples shown in Figure 8-2 might not look much like Text widgets, but trust me, they are (they would look much more like Text widgets if there were scrollbars associated with each widget, but we were trying to save space in the screenshot)! Figure 8-2 also shows -width and -height options to force smaller size.

Figure 8-2

Figure 8-2. Text widgets showing different -relief values

8.2.5. Tab Stops

The default setup for Text widget tab stops is every eight characters. Each tab equals eight spaces (but it doesn't actually use spaces). You can replace this default setting by using the -tabs option as follows:

-tabs => [qw/2 center/]   # Place tabs every 2 pixels
-tabs => [2, "center"]    # The same thing, different syntax

The argument that goes with -tabs is an anonymous list that specifies positions in which to place each of the tab stops. You can also specify an optional justification value for each tab stop (as in the preceding example) after each tab stop's numerical value. This all sounds much more confusing than it really is. Here are some examples to help clarify things:

-tabs => [qw/1i center/]   # every inch, text centered on tab-stop
-tabs => [qw/1i 1.5i/]     # ts at 1 inch, 1.5 inch and every .5 inch after

The default justification is "left". The possible justification values are "left", "right", "center", and "numeric".

When you specify the values (whether in centimeters, inches, or pixels), they are not cumulative. The list ["1i", "1.5i"] translates to one tab stop 1 inch from the left edge of the Text widget and the next tab stop 1.5 inches from the left edge. If the specified list isn't long enough to span the entire window, the distance between the last two tab stops specified will be repeated across the screen.

Of course, setting up new tab stops is pretty useless unless you're doing major text editing; in most cases, you'll leave this option alone.

You can reset the tab stops back to the default by setting -tabs to undef:

$text->configure(-tabs => undef);


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