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 color visual variable that maps optimal colors 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 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 a continuous color visualization 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 visualization 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 theme String optional Determines which values will be emphasized in the continuous ramp and the map. Valid 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. 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 color 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 color 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", but isn't required for layers with a mesh geometry type. symbolType String optional The type of symbol to generate. This depends on the view in which you are working and the desired visualization. This parameter does not need to be specified for layers with a mesh geometry type. 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. A SceneView instance must be provided to the view parameter if this option is used. colorMixMode String optional This option only applies to generating renderers for mesh SceneLayers. Specifies how the symbol's color is applied to the geometry color/texture. See the documentation in FillSymbol3DLayer.material for more context. See the table below for possible values. Value Description tint Applies the symbol color to the desaturated geometry/texture color. replace Removes the geometry/texture color and applies the symbol color. multiply Multiplies geometry/texture color value with the symbol color value. The result is a darker color. Multiplying with white keeps the geometry color the same. Default value: replace

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 colorParams = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY",
  theme: "above-and-below"
};

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

createVisualVariable(params){Promise}

This method generates a color visual variable 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, field, and theme. 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.

Parameters:

params Object Input parameters for generating a color visual variable 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 variable 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 theme String optional Determines which values will be emphasized in the continuous ramp and the map. Valid 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. 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 color 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 color 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, except for layers with a mesh geometry type. 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, except for layers with a mesh geometry type. A view must be provided if this property is set to true.

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 colorParams = {
  layer: layer,
  basemap: map.basemap,  // "gray"
  field: "POP_POVERTY",
  normalizationField: "TOTPOP_CY",
  theme: "above-and-below"
};

// when the promise resolves, apply the visual variable to the renderer
colorRendererCreator.createVisualVariable(colorParams)
  .then(function(response){
    var renderer = layer.renderer.clone();
    renderer.visualVariables = [ response.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.

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.

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 createVisualVariable() method. See the table below for details of each property.

Properties:

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.

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

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.

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.