---
name: "Tk::Dial"
section: "3pm"
platform: "linux"
package: "perl-tk"
version: "1:400.202-9"
release: "Debian 2.0 (Hamm)"
platforms: ["linux"]
url: "https://new.carta.tech/Tk::Dial"
---

# Tk::Dial(3pm)

an alternative to the scale widget

## NAME

Dial - an alternative to the scale widget

## SYNOPSIS

```
 use Tk::Dial;
```

```
 $dial = $top->Dial(-margin =>  20,
                    -radius =>  48,
                    -min    =>   0,
                    -max    => 100,
                    -value  =>   0,
                    -format => '%d');
```

```
 margin - blank space to leave around dial
 radius - radius of dial
 min, max - range of possible values
 value  - current value
 format - printf-style format for displaying format
```

Values shown above are defaults.

## DESCRIPTION

A dial looks like a speedometer: a 3/4 circle with a needle indicating the current value.  Below the graphical dial is an entry that displays the current value, and which can be used to enter a value by hand.

The needle is moved by pressing button 1 in the canvas and dragging. The needle will follow the mouse, even if the mouse leaves the canvas, which allows for high precision. Alternatively, the user can enter a value in the entry space and press Return to set the value; the needle will be set accordingly.

## TO DO

```
 Configure
 Tick marks
 Step size
```

## AUTHORS

Roy Johnson, rjohnson@shell.com

Based on a similar widget in XV, a program by John Bradley, bradley@cis.upenn.edu

## HISTORY August 1995: Released for critique by pTk mailing list