class_="gauge"

Using <widget class_="gauge"> creates a linear or radial gauge that displays scalar data on a specified range of values. (Available as of prod-9)

Syntax

<dynamic>
  <widget class_="gauge" type_="radial|linear" reading_="[VALUE]"/>
</dynamic>

Attributes

label_
Accepts text that is used as a label for the widget.
labelpos_
Accepts a string that specifies the position of the label for the widget.

Valid values are:

  • left
  • right
  • top
  • bottom

The default is left.

labelwidth_
Accepts an integer that specifies the width of the label for the widget.

If the length of the string specified by the label_ attribute is greater than the value specified for labelwidth_, the text will wrap over multiple lines.

If the labelwidth_ attribute is not specified, the default width is the length of the string specified by the label_ attribute.

reading_
Specifies the values that should be displayed by the indicators on the gauge.
This attribute accepts either:
  • A numeric value to display a single indicator at that particular value on the gauge
  • A comma-separated list of values to display multiple indicators on the gauge
Each value provided to reading_ may be specified as:
  • A scalar value
  • An expression that resolves to a scalar value
  • A column name
    Note: If a column name is present in the reading_ attribute, <layer name="reading"> must be used. See <layer name="reading"> for more information.

If the reading_ attribute is omitted, a <layer name="reading"> must be provided.

type_
Specifies the type of gauge to display.

Valid values are:

radial
Displays a radial gauge.
linear
Displays a linear gauge.

The default is radial.

colors_
Accepts a comma-separated string of values specifying the colors of the indicators on the gauge widget. Each value in this list corresponds to an indicator defined by the reading_ attribute.
Note: If the number of values specified in this attribute is not the same as the number of indicators specified by the reading_ attribute, an error is returned.

Each color can be specified as:

  • Any valid HTML color name (e.g., red, blue, cyan)
  • A hex value (e.g., #d12345)

For example, if reading_="25,75" is specified, colors_="red,blue" will specify that the indicator that points to the first value is red and the indicator that points to the second value is blue.

indicators_
Accepts a comma-separated string of values specifying the types of indicators on a gauge widget when type_="linear". Each value in this list corresponds to an indicator defined by the reading_ attribute.
Note: If the number of values specified in this attribute is not the same as the number of indicators specified by the reading_ attribute, an error is returned.

Valid values are:

arrow
Use an arrow to point to the value on the gauge widget.
fill
Draw a fill line to indicate the value on the gauge widget.

For example, if reading_="25,75" is specified, indicators_="fill,arrow" will specify that the indicator associated with the first value is a fill line and the indicator that points to the second value is an arrow.

If this attribute is omitted, arrows are used by default.

electric_
Specifies whether to animate the gauge indicators to their initial position or when their associated values change.

When electric_ is set to 1, the indicators are animated. When electric_ is set to 0, the animation is disabled.

The default is 1.

min_
Accepts an integer value that will displayed as the lowest possible value on the gauge.
max_
Accepts an integer value that will be displayed as the highest possible value on the gauge.
minorticks_
Specifies whether the gauge shows minor tick marks.

If minorticks_="1", the gauge shows minor tick marks.

If minorticks_="0", the gauge omits minor tick marks.

The default value is 0.

majorticks_
Specifies whether the gauge shows major tick marks.

If majorticks_="1", the gauge shows major tick marks.

If majorticks_="0", the gauge omits major tick marks.

The default value is 0.

minor_
The minor_ attribute accepts an integer value that specifies the spacing between the minor ticks on the gauge.

If you set minorticks_=1 but do not specify the spacing with minor_, the gauge widget will provide appropriate default values for the minor ticks.

major_
The major_ attribute accepts an integer value that specifies the spacing between the major ticks on the gauge.

If you set majorticks_=1 but do not specify the spacing with major_, the gauge widget will provide appropriate default values for the major ticks.

arcbeg_
Accepts an integer value between -180 and 180. The value provided specifies the position of the beginning of the scale in degrees from -180 (the bottom of the radial gauge).
Note: This attribute is only valid when type_="radial".
arcend_
Accepts an integer value between -180 and 180. The value provided specifies the position of the end of the scale in degrees from 180 (the top of the radial gauge).
Note: This attribute is only valid when type_="radial".
orientation_
Specifies the orientation of the gauge widget.
Note: The orientation_ attribute is only applicable when type_="linear".

Valid values are:

  • horizontal
  • vertical

The default is horizontal.

labels_
Accepts a string that specifies where to display labels of values for the gauge when type_="radial".

Valid values are:

  • outside
  • inside
  • none

The default is inside.

maxcols_
Accepts an integer that specifies the maximum number of columns in which the query associated with a <layer name="reading"> can result.
Note: This is only applicable when the reading_ attribute is omitted.

The default is 10.

minorticks_
Specifies whether the gauge shows minor tick marks.

If minorticks_="1", the gauge shows minor tick marks.

If minorticks_="0", the gauge omits minor tick marks.

The default value is 0.

majorticks_
Specifies whether the gauge shows major tick marks.

If majorticks_="1", the gauge shows major tick marks.

If majorticks_="0", the gauge omits major tick marks.

The default value is 0.

Example

The following example displays a linear gauge that ranges from a minimum value of 0 to a maximum value of 100. There are major ticks on the gauge at an interval value of 20 and minor ticks at an interval value of 2. (If you do not specify the value of minor_ or major_, the gauge widget determines appropriate tick spacing.) There are two indicators on the gauge. The first is at position 20 and is a fill indicator that is colored red; the second is at position 80 and is an arrow indicator that is colored blue. 

<dynamic>
  <widget class_="gauge" type_="linear" width_="300" 
   min_="0" max_="100" minorticks_="1" majorticks_="1"
   reading_="20,80" colors_="red,blue"
   indicators_="fill,arrow"/>
</dynamic>

Example: Gauge with slider

The following example uses a slider widget to determine the setting of the gauge widget. The initial value is set to 5. As the value of the slider widget changes, the gauge widget changes accordingly, since the reading_attribute is set to the value of the dynamic variable associated with the slider widget (slidervar). Because the electric_ attribute is set to 1, the indicator on the gauge widget moves smoothly from one value to the next as the slider widget is changed.

<dynamic slidervar="5">
  <layout arrange_="v">
    <widget class_="slider" min_="0" max_="10" 
     sliderwidth_="300" value_="@slidervar"/>
    <widget class_="gauge" min_="0" max_="10" width_="300" 
     colors_="red" reading_="{@slidervar}" electric_="1"/>
  </layout>
</dynamic>