controlwidget3tk

Usage

Overview

The controlwidget package focuses on the display and interactive control of numerical values. It mimicks several of the meters and controls found in laboratory settings but also daily life: volt meters, equalizers and tachometers to name a few. They can be seen as alternatives for the scale widget.

Note: The package has not sofar been tested extensively, and that may result in an unexpected appearance if you use sizes that are different than the defaults. Also not all options for the coloring of the various parts and fonts and so on have been tested, so that may be another source of bugs.

A last note: some parts have not been included in any option, most notably the colors of parts that require lighter and darker shades to cooperate.

Types of widgets

The package distinguishes several typed of widgets:

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Vertical meters: the value of the variable is translated into a vertical position, like with the coloured bars you find on your stereo installation.

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Angle displays: the value of the variable is related to the angle of a needle, like with tachometers.

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Interactive widgets: most widgets allow you to change the value of the variable by pressing the mouse button on the needle and shifting it up and down or left and right.

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Non-interactive widgets: some widgets, like the thermometer widget, do not allow such interaction.

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Logical or choice widgets: some widgets display the values as either on/off (or true/false) or as one of a set of discrete choices.

All widgets have in common, however, that you can connect them to a variable and that changing the variable changes the display. Forthermore, all widgets have the set and get methods to interact with the value that the widget displays (whether that is stored in a global variable or not).

They also have in common that their appearance and behaviour is determined by one or more options that you can set at creation time and often later on as well. The widgets are all based on the snit package, so that the methods configure and cget are available to set and get these options.

Commands

Currently the package contains these widgets of the vertical meter type:

::controlwidget::meter w args

Create a vertical meter consisting of an axis and a moveable arrow.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the variable to be associated with the meter

background color

Background color for the widget

height pixels

Height of the widget

width pixels

Width of the widget

arrowthickness pixels

Thickness of the displayed arrow in pixels

arrowcolor color

Color of the displayed arrow

readonly boolean

Whether the arrow can be moved interactively or not

::controlwidget::slider w args

Create a widget containing one or more vertical sliders and an axis. You can shift the slider handles interactively via the mouse.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the (list) variable to be associated with the widget

number integer

Number of sliders in the widget

background color

Background color for the widget

height pixels

Height of the widget

width pixels

Width of the widget

sliderthickness pixels

Thickness of the slider handles

sliderwidth color

Width of the slider handles

troughwidth color

Width of the troughs holding the sliders

::controlwidget::equalizerBar w args

Create a widget containing one or more vertical bars resembling those found on hifi graphical equalizers. Note that it is a read-only widget.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the (list) variable to be associated with the widget

number integer

Number of bars in the widget

background color

Background color for the widget

height pixels

Height of the widget

width pixels

Width of the widget

barwidth pixels

Width of the bars

segments integer

Number of segments the bars are divided in

safecolor color

Color for values lower than the warning level

warningcolor color

Color for values greater than the warning level

warninglevel double

Threshold value, determines at what level the color changes

::controlwidget::thermometer w args

Create a thermometer widget (read-only)

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the (list) variable to be associated with the widget

background color

Background color for the widget

height pixels

Height of the widget

width pixels

Width of the widget

linethickness pixels

Thickness of the line representing the "temperature"

linecolor color

Color of the line

These widgets all use a vertical axis and have the following options in common for configuring the axis:

The package contains the following widget based on angle displays:

::controlwidget::voltmeter w args

Create a voltmeter-like widget.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the variable to be associated with the meter

value value

Value for the meter (if not associated with a variable)

min value

The minimum value for data in the display

max value

The maximum value for data in the display

labels list

The labels to be shown along the scale. (These are simply considered texts, so no relation with the minimum and maximum perse)

title string

String to be shown below the dial

width pixels

The width of the widget

height pixels

The height of the widget

borderwidth pixels

The width of the border surrounding the entire widget

relief string

The relief of the border surrounding the entire widget

highlightthickness pixels

The width of the border to indicate the widget has keyboard focus

labelfont fontname

Font of the labels to the scale

titlefont fontname

Font of the title below the dial

dialcolor color

Color of the dial holding the needle

needlecolor color

Color of the needle

scalecolor color

Color of the scale (arc and tickmarks)

labelcolor color

Color of the labels to the scale

titlecolor color

Color of the title below the dial

::controlwidget::tachometer w args

Create a tachometer-like widget.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget. In addition to the ones given for the voltmeter widget:

variable name

Name of the variable to be associated with the meter

value value

Value for the meter (if not associated with a variable)

dangerlevel value

Level above which values are indicated with a different color

dangercolor color

Color for the values above the "danger level"

dangerwidth pixels

Width for the colored band indicating the "danger level"

pincolor color

Color for the needle and the pin

::controlwidget::rdial w args

Create a rotating dial. You can drag the dial to change the value. With the shift button depressed the value changes slowly, with the control button depressed it changes fast. Similarly, you can control the dial via the mouse wheel, with the shift and control button working in the same way as with the mouse pointer. Note: The shift and control buttons currently have no effect on Windows.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget:

variable name

Name of the variable to be associated with the dial

value value

Value for the dial (if not associated with a variable)

orient string

Whether a horizontal disk/dial is required ("horizontal") or a vertical one ("vertical")

step value

Initial step for incrementing or decrementing the value

bindwheel value

Step size for controlling the dial's value via the mouse wheel

slow value

Factor on the step size for incrementing or decrementing the value slowly

fast value

Factor on the step size for incrementing or decrementing the value fast

scale value

Scale value to be applied to the actual value

callback command

Command to be called when the value changes

width pixels

The width of the widget

height pixels

The height of the widget

background color

The background color of the widget (coloring of the disk/dial)

foreground color

The foreground color of the widget (the marker lines)

All these widgets have the following methods:

$widget get

Return the current value or values shown in the widget

$widget set value

Reset the value or values shown in the widget. If the widget is associated with a variable, that variable is set as well.

value double/list

New value or values for the widget

Two further widgets are available, meant to display logical values:

::controlwidget::led w args

Create a LED-like widget.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget. In addition to the ones given for the voltmeter widget:

variable name

Name of the variable to be associated with the LED

size pixels

Diameter of the LED widget

on color

Color to use for the "on" state

off color

Color to use for the "off" state

::controlwidget::radioMatrix w args

Create a matrix of radio buttons that behaves as a single widget.

widget w (in)

Name of the widget to be created.

arguments args (in)

List of key-value pairs, controlling the appearance and behaviour of the widget. In addition to the ones given for the voltmeter widget:

variable name

Name of the variable to be associated with the matrix

orient string

The way the radio buttons are to be arranged (horizontal or vertical first)

rows integer

Number of rows in the matrix

columns integer

Number of columns in the matrix

command list

Command associated with the radio buttons. Invoked when the active radio button changes.

The LED widget has the following public methods:

$led on

Set the state to "on"

$led off

Set the state to "off"

$led setstate state

Set the state according to the value of "state"

state boolean (in)

New state for the LED widget

The radioMatrix widget has two public methods:

$matrix get

Return the index of the currently selected radio button

$matrix set index

Select the radio button with index "index"

index integer

Index of the radio button to be set

Acknowledgments

The code for most of these widgets first appeared on the Wiki. In many cases, Arjen Markus merely refactored the code a bit and "snitified" some of them. The original code was developed by the following people:

Bugs, ideas, feedback

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category controlwidget of the Tklib Trackers [http://core.tcl.tk/tklib/reportlist]. Please also report any ideas for enhancements you may have for either package and/or documentation.

Keywords

controlling, displaying, numerical values, scale widget