LegendHelper

LegendHelper

new LegendHelper(tableColumn, tableStyleopt, regionProvideropt, nameopt)

Source:

Legends for table columns depend on both the table style and the selected column. This class brings the two together to generate a legend. Its key output is legendUrl.

Parameters:
Name Type Attributes Description
tableColumn TableColumn

The column whose values inform the legend.

tableStyle TableStyle <optional>

The styling for the table.

regionProvider RegionProvider <optional>

The region provider, if region mapped. Used if no table column set.

name String <optional>

A name used in the legend if no active column is selected.

Methods

getColorArrayFromValue(valueopt) → {Array.<Number>}

Source:

Maps an absolute value to a color array, based on the legend.

Parameters:
Name Type Attributes Description
value Number <optional>

The absolute value.

Returns:

The color, as an array [r, g, b, a]. If there is no table column selected, use a random colour. If the value is null, use the nullColor. If no value is provided, or no color bins are defined, use the nullColor.

Type
Array.<Number>

getColorFromValue(valueopt) → {Color}

Source:

Maps an absolute value to a Color, based on the legend.

Parameters:
Name Type Attributes Description
value Number <optional>

The absolute value.

Returns:

The color. If no value is provided, uses a default color.

Type
Color

getScaleFromValue(valueopt) → {Number}

Source:

Maps an absolute value to a scale, based on tableColumnStyle.

Parameters:
Name Type Attributes Description
value Number <optional>

The absolute value.

Returns:

The scale.

Type
Number

legendUrl() → {LegendUrl}

Source:

Returns the legendUrl for this legend. Can be called directly after instantiation.

Returns:

The Legend URL object for the legend, with its url being a base64-encoded PNG.

Type
LegendUrl