The Scale Widget (Perl in a Nutshell, 2nd Edition)

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21.13. 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, -highlight-background, -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 is 0).
-label => string: The string to use as a label for the slider.
-length => amount: The length of the scale.
-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 auto-repeats. 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 is 1).
-showvalue => boolean: Whether to show the current value of the slider (default is 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).
-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.

21.13.1. 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.


21.12. The Canvas Widget		21.14. The Menubutton Widget