Method Overview

Method Details

createContinuousRenderer(params){Promise}

Generates a Renderer that may be applied directly to the layer used to call this method. The renderer contains a continuous size visual variable that maps marker sizes to specific stop values based on queried statistics from the indicated field or expression.

In most cases you will provide a layer, basemap, and field 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 to use in the visualization.

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 Input parameters for generating 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 The layer for which the renderer is generated. field String The name of the field whose data will be queried for statistics and used for the basis of the data-driven visualization. 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. basemap String | Basemap optional The named string of the Esri basemap or basemap object that will be paired with the output visualization. Default Value: gray sizeScheme PointSizeScheme | PolylineSizeScheme | PolygonSizeScheme 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. 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 size visual variable. 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 size visual variable. 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. view SceneView optional The SceneView instance in which the visualization will be rendered. This parameter is required if symbolType = "3d-volumetric" or "3d-volumetric-uniform". symbolType String optional The type of symbol to generate. This depends on the view in which you are working and the desired visualization. Known values are described below. Default Value: 2d 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 sized uniformly, for example with spheres. A SceneView instance must be provided to the view parameter if this option is used.

Returns:

Type	Description
Promise	Resolves to an instance of ContinuousRendererResult.

Example:

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

// visualization based on field and normalization field
var sizeParams = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY",
};

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

createVisualVariables(params){Promise}

This method generates an array of size visual variables with default stops that are optimally chosen based on the statistics queried for the indicated field or expression and mapped to appropriate sizes.

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.

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 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 exactly one size visual variable unless the axis parameter is set to "height".

Parameters:

params Object Input parameters for generating 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 The layer for which the visual variables are generated. field String The name of the field whose data will be queried for statistics and used for the basis of the data-driven visualization. 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. basemap String | Basemap optional The named string of the Esri basemap or basemap object that will be paired with the output visualization. Default Value: gray sizeScheme PointSizeScheme | PolylineSizeScheme | PolygonSizeScheme 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. 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 size visual variable. 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 size visual variable. view SceneView optional The SceneView instance in which the visualization will be rendered. This property is only applicable to generating visualizations with 3D symbols. 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. axis Boolean optional 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 Default Value: all

Returns:

Type	Description
Promise	Resolves to an instance of VisualVariableResult.

Example:

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

// visualization based on field and normalization field
var sizeParams = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY"
};

// when the promise resolves, apply the visual variables to the renderer
sizeRendererCreator.createVisualVariables(sizeParams)
  .then(function(response){
    var renderer = layer.renderer.clone();
    renderer.visualVariables = response.visualVariables;
    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.

visualVariables SizeVisualVariable[] Size visual variables configured based on the statistics of the data and the given basemap and scheme.

sizeScheme PointSizeScheme | PolylineSizeScheme | PolygonSizeScheme The size scheme used by the visual variables.

defaultValuesUsed Boolean Indicates whether default values are 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 data from the given field name or expression.

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

VisualVariableResult

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

Properties:

visualVariables SizeVisualVariable[] An array of size visual variables configured based on the statistics of the data and the view scale.

sizeScheme PointSizeScheme | PolylineSizeScheme | PolygonSizeScheme The size scheme used by the main 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 variable. This includes information related to UI inputs from sliders and selected themes.