var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "REGION",
  defaultSymbol: { type: "simple-fill" },  // autocasts as new SimpleFillSymbol()
  uniqueValueInfos: [{
    // All features with value of "North" will be blue
    value: "North",
    symbol: {
      type: "simple-fill",  // autocasts as new SimpleFillSymbol()
      color: "blue"
    }
  }, {
    // All features with value of "East" will be green
    value: "East",
    symbol: {
      type: "simple-fill",  // autocasts as new SimpleFillSymbol()
      color: "green"
    }
  }, {
    // All features with value of "South" will be red
    value: "South",
    symbol: {
      type: "simple-fill",  // autocasts as new SimpleFillSymbol()
      color: "red"
    }
  }, {
    // All features with value of "West" will be yellow
    value: "West",
    symbol: {
      type: "simple-fill",  // autocasts as new SimpleFillSymbol()
      color: "yellow"
    }
  }],
  visualVariables: [{
    type: "opacity",
    field: "POPULATION",
    normalizationField: "SQ_KM",
    // features with 30 ppl/sq km or below are assigned the first opacity value
    stops: [{ value: 100, opacity: 0.15 },
            { value: 1000, opacity: 0.90 }]
  }]
};

var layer = new FeatureLayer({
  url: "http://url.to.service",
  renderer: renderer
});

Property Overview

Property Details

authoringInfoAuthoringInfoautocast inherited

Authoring metadata only included in renderers generated from one of the Smart Mapping creator methods, such as sizeRendererCreator.createContinuousRenderer() or colorRendererCreator.createContinuousRenderer(). This includes information from UI elements such as sliders and selected classification methods and themes. This allows the authoring clients to save specific overridable settings so that next time it is accessed via the UI, their selections can be remembered.

backgroundFillSymbolFillSymbol|PolygonSymbol3Dautocast

Since: ArcGIS API for JavaScript 4.7

This property is only relevant When symbolizing polygon features with marker symbols (or IconSymbol3DLayer) in the uniqueValueInfos of this renderer. This is usually done when adding a SizeVisualVariable to the visualVariables) in a bivariate visualization (color indicates a type-based value and size indicates the value of a separate numeric field). Use this property to set a background FillSymbol (or PolygonSymbol3D if visualizing data in 3D) to visualize the boundaries of each polygon.

Example:

// this symbol will be applied to all features. It is only
// necessary when visualizing polygon data with icons.
renderer.backgroundFillSymbol = {
  type: "simple-fill",
  outline: {
    width: 1,
    color: "gray"
  }
};

declaredClassStringreadonly inherited

Since: ArcGIS API for JavaScript 4.7

The name of the class. The declared class name is formatted as esri.folder.className.

defaultLabelString

Label used in the Legend to describe features assigned the default symbol. The default symbol is used to draw all features with unspecified, unmatched values.

defaultSymbolSymbolautocast

The default symbol used to draw a feature whose value is not matched or specified by the renderer. If null, unmatched features will not be assigned a symbol.

Known Limitations

SceneLayers with a mesh geometryType will display unmatching features with a generic symbol even if the defaultSymbol is null.

fieldString

The name of the attribute field the renderer uses to match unique values or types.

Example:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "RANK",  // values returned by this function will
                     // be used to render features by type
  uniqueValueInfos: [
    {
      value: "high",  // features labeled as "High"
      symbol: sym1  // will be assigned sym1
    }, {
      value: "medium",  // features labeled as "Medium"
      symbol: sym2  // will be assigned sym2
    }, {
      value: "low",  // features labeled as "Low"
      symbol: sym3  // will be assigned sym2
    }
  ]
};

field2String

If needed, specifies the name of an additional attribute field the renderer will use to match values. For example, if you specify two fields:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "REGION",
  field2: "RANK",
  fieldDelimiter: ", ",  // comma + space used to separate values from all fields
  uniqueValueInfos: [
    {
      value: "North, 1",  // features in the "North" region and a rank of 1
      symbol: sym1  // will be assigned sym1
    }, {
      value: "North, 2",  // features in the "North" region and a rank of 2
      symbol: sym2  // will be assigned sym2
    },
    ...
  ]
};

All combinations of values of field and field2 are unique values and may have their own symbol.

See also:

• fieldDelimiter

field3String

If needed, specify the name of a third attribute field the renderer will use to match values. For example, if you specify three fields:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "REGION",
  field2: "RANK",
  field3: "CLASS",
  fieldDelimiter: ", ",  // comma + space used to separate values from all fields
  uniqueValueInfos: [
    {
      value: "North, 1, medium",  // features in the "North" region, a rank of 1, and "medium" class
      symbol: sym1  // will be assigned sym1
    }, {
      value: "North, 2, medium",  // features in the "North" region, a rank of 2, and a "medium class
      symbol: sym2  // will be assigned sym2
    },
    ...
  ]
};

All combinations of values of field, field2, and field3 are unique values and may have their own symbol.

See also:

• fieldDelimiter

fieldDelimiterString

String inserted between the values if multiple attribute fields are specified.

See also:

• field2

• field3

Example:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "REGION",
  field2: "RANK",
  fieldDelimiter: ", ",  // comma + space used to separate values from all fields
  uniqueValueInfos: [
    {
      value: "North, 1",  // features in the "North" region and a rank of 1
      symbol: sym1  // will be assigned sym1
    }, {
      value: "North, 2",  // features in the "North" region and a rank of 2
      symbol: sym2  // will be assigned sym2
    },
    ...
  ]
};

legendOptionsObject

An object providing options for displaying the renderer in the Legend.

Property:

title String optional Describes the variable driving the visualization. This is displayed as the title of the corresponding renderer in the Legend and takes precedence over a field alias or valueExpressionTitle.

Example:

renderer.legendOptions = {
  title: "Classification (high/low)"
};

typeStringreadonly

The type of Renderer. For UniqueValueRenderer this value is always unique-value.

uniqueValueInfosObject[]

Each element in the array is an object that provides information about a unique value associated with the renderer. Each object has the following specification:

Properties:

value String | Number The unique value used to classify features.

symbol Symbol The symbol used to style features whose value matches value. This value may be autocast by specifying the symbol type.

label String optional Label used to describe features matched to this unique value in the Legend.

valueExpressionString

An Arcade expression evaluating to either a string or a number. This expression can reference field values using the $feature global variable and perform mathematical calculations and logical evaluations at runtime.

This property is typically used as an alternative to field for data-driven visualizations.

Example:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  valueExpression: "When($feature.count < 20, 'low', $feature.count >= 20 && $feature.count < 70, 'moderate', $feature.count >=70, 'high', 'other')",
  uniqueValueInfos: [ ... ],  // assigns symbols to features evaluating to 'low', 'moderate', or 'high'
};

valueExpressionTitleString

The title identifying and describing the associated Arcade expression as defined in the valueExpression property. This is displayed as the title of the corresponding renderer in the Legend in the absence of a provided title in the legendOptions property.

Example:

renderer.valueExpression = "IIF($feature.POP > 500000, 'high', 'low')";
renderer.valueExpressionTitle = "Classification";

visualVariablesObject[]

Visual variables define the parameters for data-driven geographic visualizations of numeric data. They allow you to easily map continuous ramps of color, size, opacity, and/or rotation to minimum and maximum data values of one of the layer's numeric attribute fields.

Visual variables can primarily be used in two ways.

1. Thematic mapping

Visual variables allow you to easily create stunning visualizations based on thematic attributes (e.g. population, education, rank, money, magnitude, etc.) in either 2D or 3D. This is accomplished by mapping data values from a numeric field attribute to color, size, and/or opacity values. The renderer then takes over and re-sizes or shades features based on the value of the given field and its position relative to the minimum and maximum values. The sample below uses three visual variables (size, color, and opacity).

2. Mapping real-world sizes

The size visual variable can be used to visualize the true sizes of features (e.g. tree canopy, road width, building height, etc.) based on their size in the real world. This can be particularly powerful when working in a 3D SceneView. The image below shows a layer of building footprints that uses visual variables to extrude each feature to the true height of the buildings based on data stored in an attribute field.

The visualVariables property of the renderer is an array of objects called "visual variables". Each object must indicate the type of visual variable to apply (e.g. color, size, opacity, rotation), the numeric field from which to drive the visualization, and the ramp of visual values to map to the data. The following list identifies each visual variable type and provides a link to the specification table of each.

Type	Object Specification	Legend Example
color	ColorVisualVariable
size	SizeVisualVariable
opacity	OpacityVisualVariable
rotation	RotationVisualVariable	-

See the Visualize features with realistic 3D symbols for an example of using multiple visual variables to visualize your data.

Known Limitations

Color and opacity visual variables must not have more than 8 stops and size visual variables must not have more than 6 stops. This does not apply to variables driven by view scale.

See also:

• Creating visualizations manually

• Visualization overview

Method Overview

Method Details

addUniqueValueInfo(valueOrInfo, symbol)

Adds a unique value and symbol to the renderer. You can provide the value and its associated symbol as individual arguments or as an info object.

Parameters:

valueOrInfo String|Number|Object The value to match. The value can be provided as an individual argument or as an info object described in uniqueValueInfos.

symbol Symbol autocast optional Autocasts from Object The symbol used to represent features matching the specified value.

Examples:

var renderer = {
  type: "unique-value",  // autocasts as new UniqueValueRenderer()
  field: "REGION",
  defaultSymbol: { type: "simple-fill" }   // autocasts as new SimpleFillSymbol()
};
// Add a unique value info for the "North" region
// using individual function arguments
renderer.addUniqueValueInfo({
  value: "North",
  symbol: {
    type: "simple-fill",  // autocasts as new SimpleFillSymbol()
    color: "blue"
  }
});

// Add a unique value info for the "West" region
// using a unique info object
renderer.addUniqueValueInfo({
  value: "West",
  symbol: new SimpleFillSymbol({
    color: "yellow"
  }),
  label: "West region"  // will display this text in legend
});

clone(){UniqueValueRenderer}

Creates a deep clone of the renderer.

Returns:

Type	Description
UniqueValueRenderer	A deep clone of the object that invoked this method.

Example:

// Creates a deep clone of the first layer's renderer
var renderer = view.map.layers.getItemAt(0).renderer.clone();

fromJSON(json){*}static

Creates a new instance of this class and initializes it with values from a JSON object generated from a product in the ArcGIS platform. The object passed into the input json parameter often comes from a response to a query operation in the REST API or a toJSON() method from another ArcGIS product. See the Using fromJSON() topic in the Guide for details and examples of when and how to use this function.

Parameter:

json Object A JSON representation of the instance in the ArcGIS format. See the ArcGIS REST API documentation for examples of the structure of various input JSON objects.

Returns:

Type	Description
*	Returns a new instance of this class.

getUniqueValueInfo(graphic){Object}

Returns rendering and legend information (as defined by the renderer) associated with the given graphic.

Parameter:

graphic Graphic The graphic whose rendering and legend information will be returned.

Returns:

Type	Description
Object	An object describing the rendering and legend information of the input graphic.

removeUniqueValueInfo(value)

Removes a unique value from the renderer.

Parameter:

value String Value to remove from uniqueValueInfos.

Example:

// removes the unique value info object for
// features in the West region. They will now
// be displayed with the default symbol and label
renderer.removeUniqueValueInfo("West");

toJSON(){Object}inherited

Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() topic in the Guide for more information.

Returns:

Type	Description
Object	The ArcGIS portal JSON representation of an instance of this class.