Method Overview

Method Details

createContinuousRenderer(params){Promise<ContinuousRendererResult>}

Generates a Renderer that may be applied directly to a Layer. The renderer contains continuous color and size visual variables that map symbols with optimal colors and sizes based on the indicated basemap to specific stop values based on queried statistics from the indicated field or expression.

In most cases you will provide a layer, basemap, field, and theme to generate this renderer. This is a scenario in which the statistics of the data aren't well known and the user doesn't know what colors and sizes to use in the visualization. You can also use a valueExpression instead of a field to visualize features based on a value returned from a script executed at runtime.

The other options are provided for convenience for more involved custom visualization authoring applications. For example, if you already generated statistics in another operation, you can pass the statistics object to the statistics parameter to avoid making an extra call to the server.

Parameters:

params Object See the table below for details of each parameter that may be passed to this method. Specification: layer FeatureLayer|SceneLayer|CSVLayer The layer for which the visual variable is generated. basemap String|Basemap optional Default Value: gray The named string or basemap object of the Esri basemap that will be paired with the output visualization. field String optional The name of the field whose data will be queried for statistics and used for the basis of the data-driven visualization. This property is ignored if a valueExpression is used. normalizationField String optional The name of the field to normalize the values of the given field. Providing a normalization field helps minimize some visualization errors and standardizes the data so all features are visualized with minimal bias due to area differences or count variation. This option is commonly used when visualizing densities. valueExpression String optional An Arcade expression that returns a number. This expression can reference field values using the $feature global variable. This property overrides the field property and therefore is used instead of an input field value. valueExpressionTitle String optional Text describing the value returned from the valueExpression. This is used by the Legend widget. sqlExpression String optional A SQL expression evaluating to a number. sqlWhere String optional A SQL where clause used to filter features for the statistics query. For example, this is useful in situations where you want to avoid dividing by zero as is the case with creating a predominance visualization. statistics SummaryStatisticsResult optional A statistics object generated from the summaryStatistics function. If statistics for the field have already been generated, then pass the object here to avoid making a second statistics query to the server. minValue Number optional A custom minimum value set by the user. Use this in conjunction with maxValue to generate statistics between lower and upper bounds. This will be the lowest stop in the returned visual variables. maxValue Number optional A custom maximum value set by the user. Use this in conjunction with minValue to generate statistics between lower and upper bounds. This will be the uppermost stop in the returned visual variables. defaultSymbolEnabled Boolean optional Enables the defaultSymbol on the renderer and assigns it to features with no value and features that do not fall within the configured data range. colorOptions Object optional Options for configuring the color portion of the visualization. Specification: theme String optional Determines which values will be emphasized in the continuous ramp and the map. Possible values are listed below. Value Description Example high-to-low High values are emphasized with strong colors. above-and-below Values centered around a given point (e.g. the average) are visualized with weak colors while other values are emphasized with strong colors. centered-on Values centered around a given point (e.g. the average) are emphasized with strong colors while other values are visualized with weak colors. extremes High and low values are emphasized with strong colors. All others are visualized with weak colors. colorScheme ColorScheme optional In authoring apps, the user may select a pre-defined color scheme. Pass the scheme object to this property to avoid getting one based on a theme and the basemap. legendOptions Object optional Provides options for setting a title to a field when an expression is provided instead of a field name. This title will represent the field in the Legend. Specification: title String The title used to represent the given field or expression in the Legend. sizeOptions Object optional Options for configuring the size portion of the visualization. Specification: sizeScheme SizeScheme optional In authoring apps, the user may select a pre-defined size scheme. Pass the scheme object to this property to avoid getting one based on the basemap. legendOptions Object optional Provides options for setting a title to a field when an expression is provided instead of a field name. This title will represent the field in the Legend. Specification: title String The title used to represent the given field or expression in the Legend. view View optional The view instance in which the visualization will be rendered. A SceneView is required if symbolType = "3d-volumetric" or 3d-volumetric-uniform. The relevant SceneView or MapView is required when a valueExpression is specified. symbolType String optional Default Value: 2d The type of symbol to generate. This depends on the view in which you are working and the desired visualization. Possible values are described below. Value Description 2d Generates a visualization using 2D symbols such as SimpleMarkerSymbol, SimpleLineSymbol, or SimpleFillSymbol. Use this option if generating a visualization for data in a MapView. 3d-flat Generates a visualization using 3D symbols with flat symbol layers such as IconSymbol3DLayer, LineSymbol3DLayer, or FillSymbol3DLayer. Use this option if generating a 2D visualization for data in a SceneView. 3d-volumetric Generates a visualization using 3D symbols with volumetric symbol layers such as ObjectSymbol3DLayer, PathSymbol3DLayer, or ExtrudeSymbol3DLayer. Use this option if generating a 3D visualization for data in a SceneView and only the symbol's height should be variable, for example with cylinders. A SceneView instance must be provided to the view parameter if this option is used. 3d-volumetric-uniform Generates a visualization using uniformly sized 3D symbols with volumetric symbol layers. Use this option if generating a 3D visualization for data in a SceneView and the symbol should be sizes uniformly, for example with spheres. A SceneView instance must be provided to the view parameter if this option is used.

Returns:

Type	Description
Promise<ContinuousRendererResult>	Resolves to an instance of ContinuousRendererResult.

Examples:

var layer = new FeatureLayer({
  url: "https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/counties_politics_poverty/FeatureServer/0"
});

// color/size univariate visualization based on field and normalization field
var params = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY",
  colorOptions: {
    theme: "above-and-below"
  }
};

// when the promise resolves, apply the renderer to the layer
colorAndSizeRendererCreator.createContinuousRenderer(params)
  .then(function(response){
    layer.renderer = response.renderer;
  });

var layer = new FeatureLayer({
  url: "https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/counties_politics_poverty/FeatureServer/0"
});

// visualization based off Arcade expression
var params = {
  layer: layer,
  basemap: "topo",
  valueExpression: "($feature.POP_POVERTY / $feature.TOTPOP_CY) * 100",
  view: view,
  sqlWhere: "TOTPOP_CY > 0",
  colorOptions: {
    legendOptions: {
      title: "% of people living in poverty"
    }
  },
  sizeOptions: {
    legendOptions: {
      title: "% of people living in poverty"
    }
  }
};

// when the promise resolves, apply the renderer to the layer
colorAndSizeRendererCreator.createContinuousRenderer(params)
  .then(function(response){
    layer.renderer = response.renderer;
  });

createVisualVariables(params){Promise<VisualVariablesResult>}

This method generates color and size visual variables, both based on the same given field or expression. These visual variables are generated with default stops that are optimally chosen based on the statistics queried for the indicated field or expression and colors based on the input basemap.

There are two different ways this method may be called. The most common case is by providing a layer, basemap, and field. This is the scenario where the statistics of the data aren't well known and the user doesn't know what colors to use. You can optionally use a valueExpression instead of a field to visualize features based on a numeric value returned from a script executed at runtime.

The other options are provided for convenience for more involved custom visualization authoring applications. For example, if you already generated statistics in another operation, you can pass the object in the statistics parameter to avoid making an extra call to the server. You can also provide a colorScheme and/or a sizeScheme if you don't want one picked for you. In this case the basemap and theme options would be ignored.

The resulting array of visual variables will contain one color visual variable, and one or two size visual variables depending on the value of the sizeOptions.axis parameter.

Parameters:

params Object Input parameters for generating color and size visual variables based on data returned from a given field or expression. See the table below for details of each parameter. Specification: layer FeatureLayer|SceneLayer|CSVLayer The layer for which the visual variable is generated. basemap String|Basemap optional Default Value: gray The named string or basemap object of the Esri basemap that will be paired with the output visualization. field String optional The name of the field whose data will be queried for statistics and used for the basis of the data-driven visualization. This property is ignored if a valueExpression is used. normalizationField String optional The name of the field to normalize the values of the given field. Providing a normalization field helps minimize some visualization errors and standardizes the data so all features are visualized with minimal bias due to area differences or count variation. This option is commonly used when visualizing densities. valueExpression String optional An Arcade expression that returns a number. This expression can reference field values using the $feature global variable. This property overrides the field property and therefore is used instead of an input field value. valueExpressionTitle String optional Text describing the value returned from the valueExpression. This is used by the Legend widget. sqlExpression String optional A SQL expression evaluating to a number. sqlWhere String optional A SQL where clause used to filter features for the statistics query. For example, this is useful in situations where you want to avoid dividing by zero as is the case with creating a predominance visualization. statistics SummaryStatisticsResult optional A statistics object generated from the summaryStatistics function. If statistics for the field have already been generated, then pass the object here to avoid making a second statistics query to the server. minValue Number optional A custom minimum value set by the user. Use this in conjunction with maxValue to generate statistics between lower and upper bounds. This will be the lowest stop in the returned visual variables. maxValue Number optional A custom maximum value set by the user. Use this in conjunction with minValue to generate statistics between lower and upper bounds. This will be the uppermost stop in the returned visual variables. colorOptions Object optional Options for configuring the color portion of the visualization. Specification: theme String optional Determines which values will be emphasized in the continuous ramp and the map. Possible values are listed below. Value Description Example high-to-low High values are emphasized with strong colors. above-and-below Values centered around a given point (e.g. the average) are visualized with weak colors while other values are emphasized with strong colors. centered-on Values centered around a given point (e.g. the average) are emphasized with strong colors while other values are visualized with weak colors. extremes High and low values are emphasized with strong colors. All others are visualized with weak colors. colorScheme ColorScheme optional In authoring apps, the user may select a pre-defined color scheme. Pass the scheme object to this property to avoid getting one based on a theme and the basemap. legendOptions Object optional Provides options for setting a title to a field when an expression is provided instead of a field name. This title will represent the field in the Legend. Specification: title String The title used to represent the given field or expression in the Legend. sizeOptions Object optional Options for configuring the size portion of the visualization. Specification: axis Boolean optional Default Value: all When set to all, a single size variable that scales uniformly in all dimensions is generated. When set to height, the result contains two size visual variables: the first one sizes the height according to the field statistics, while the second defines a constant size for width and depth. Possible Values: all | height sizeScheme SizeScheme optional In authoring apps, the user may select a pre-defined size scheme. Pass the scheme object to this property to avoid getting one based on the basemap. legendOptions Object optional Provides options for setting a title to a field when an expression is provided instead of a field name. This title will represent the field in the Legend. Specification: title String The title used to represent the given field or expression in the Legend. view View optional When generating 3D symbols, a SceneView instance is required. The relevant SceneView or MapView is required when a valueExpression is specified. worldScale Boolean optional Indicates if the size units of the symbols will be in meters. This should be true when generating visualizations with 3D volumetric symbology. A view must be provided if this property is set to true.

Returns:

Type	Description
Promise<VisualVariablesResult>	Resolves to an instance of VisualVariablesResult.

Examples:

var layer = new FeatureLayer({
  url: "https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/counties_politics_poverty/FeatureServer/0"
});

// color/size univariate visualization based on field and normalization field
var params = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY",
  colorOptions: {
    theme: "above-and-below"
  }
};

// when the promise resolves, apply the visual variables to the renderer
colorAndSizeRendererCreator.createVisualVariables(params)
  .then(function(response){
    var renderer = layer.renderer.clone();
    renderer.visualVariables = [ response.color.visualVariable, response.size.visualVariable ];
    layer.renderer = renderer;
  });

var layer = new FeatureLayer({
  url: "https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/counties_politics_poverty/FeatureServer/0"
});

// visualization based off an Arcade expression
var params = {
  layer: layer,
  basemap: "topo",
  valueExpression: "($feature.POP_POVERTY / $feature.TOTPOP_CY) * 100",
  sqlExpression: "( POP_POVERTY / TOTPOP_CY ) * 100",
  colorOptions: {
    legendOptions: {
      title: "% of people living in poverty"
    }
  },
  sizeOptions: {
    legendOptions: {
      title: "% of people living in poverty"
    }
  }
};

// when the promise resolves, apply the visual variables to the renderer
colorAndSizeRendererCreator.createVisualVariables(params)
  .then(function(response){
    var renderer = layer.renderer.clone();
    renderer.visualVariables = [ response.color.visualVariable, response.size.visualVariable ];
    layer.renderer = renderer;
  });

Type Definitions

ContinuousRendererResult

The result object of the createContinuousRenderer() method. See the table below for details of each property.

Properties:

renderer ClassBreaksRenderer The renderer object configured to best match the given basemap and the spread of the data. Set this on a layer's renderer property to update its visualization.

color Object Object containing visual variable and scheme information for the color portion of the visualization. Specification: visualVariable ColorVisualVariable A color visual variable configured based on the statistics of the data and the given basemap and scheme. colorScheme ColorScheme The color scheme used by the visual variable.

size Object Object containing visual variable and scheme information for the size portion of the visualization. Specification: visualVariables SizeVisualVariable[] The size visual variable(s) configured based on the statistics of the data and the view scale. sizeScheme SizeScheme The size scheme used by the visual variable.

defaultValuesUsed Boolean Indicates whether default values were used in the absence of sufficient data and/or statistics from the layer. Default values are typically used when all features have the same field value or no value at all.

statistics SummaryStatisticsResult Basic statistics returned from a query to the service for the given field or expression.

basemapId String The ID of the basemap used to determine the optimal fill color of the features.

VisualVariablesResult

The result object of the createVisualVariables() method. See the table below for details of each property.

Properties:

color Object Object containing visual variable and scheme information for the color portion of the visualization. Specification: visualVariable ColorVisualVariable A color visual variable configured based on the statistics of the data and the given basemap and scheme. colorScheme ColorScheme The color scheme used by the visual variable.

size Object Object containing visual variable and scheme information for the size portion of the visualization. Specification: visualVariables SizeVisualVariable[] The size visual variable(s) configured based on the statistics of the data and the view scale. sizeScheme SizeScheme The size scheme used by the visual variable.

defaultValuesUsed Boolean Indicates whether default values were used in the absence of sufficient data and/or statistics from the layer. Default values are typically used when all features have the same field value or no value at all.

statistics SummaryStatisticsResult Basic statistics returned from a query to the service for the given field or expression.

basemapId String The ID of the basemap used to determine the optimal fill color of the features.

authoringInfo AuthoringInfo Authoring information related to the creation of the visual variables. This includes inforamation related to UI inputs from sliders and selected themes.