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Perl in a Nutshell

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Perl/Tk
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18.13 The Scale Widget

Create a "slider" widget representing a numeric value with the Scale method.

$parent->Scale(options);
The standard configuration options that apply to Scale are: -activebackground, -background, -bg, -borderwidth, -bw, -cursor, -font, -foreground, -fg, -highlightbackground, -highlightcolor, -highlightthickness, -relief, -state, -takefocus, and -width.

Other options are:

-bigincrement => amount

The amount to change the slider when using large increments. Default is 0, which means 1/10 of the scale.

-command => callback

Pointer to a function that will be called for every incremental change in the slider.

-digits => amount

The number of digits to keep when converting from a number to a string.

-from => n

Low end of the scale (default = 0).

-label => string

The string to use as a label for the slider.

-length => amount

The length of the slider.

-orient => direction

The orientation of the slider. Values can be either 'vertical' (default) or 'horizontal'.

-repeatdelay => milliseconds

Determines the number of milliseconds to hold down an arrow before it will auto-repeat. Default is 300.

-repeatinterval => milliseconds

Determines the number of milliseconds between auto-repeats once it is started. Default is 100.

-resolution => value

The increments that the scale will change by (default = 1).

-showvalue => boolean

Whether to show the current value of the slider (default = 1).

-sliderlength => amount

The size of the slider. Default is 25 pixels.

-tickinterval => n

The number of "ticks" to display for the slider. Default is 0 (no ticks).

-to => n

The top value of the scale (default is 100).

-troughcolor => color

Changes the color of the trough.

-variable => \$variable

Assigns the value of the slider to the specified variable.

18.13.1 Scale Methods

In addition to configure and cget, the following methods are defined for the Scale widget:

get

Returns the current value if given no arguments. If given x and y coordinates as the first and second arguments, returns the value of the scale at that position.

set

Assigns the value associated with the scale.

coords

Returns the x and y coordinates associated with the value given in the first argument.

identify

Returns "slider", "trough1", "trough2", or "", depending on which part of the scale corresponds to the given x, y coordinates.


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