require(["esri/renderers/visualVariables/OpacityVariable"], (OpacityVariable) => { /* code goes here */ });
import OpacityVariable from "@arcgis/core/renderers/visualVariables/OpacityVariable.js";
esri/renderers/visualVariables/OpacityVariable
The opacity visual variable defines the opacity of each feature's symbol based on a numeric field value or number returned from an expression. You must specify stops to construct the opacity ramp.
const opacityVisualVariable = {
type: "opacity",
field: "PERCENTAGE",
// maps data values to opacity values
stops: [
{ value: 0, opacity: 0.1 },
{ value: 100, opacity: 1 }
]
};
renderer.visualVariables = [ opacityVisualVariable ];
// opacity visual variable with arcade
const opacityVisualVariable = {
type: "opacity",
// calculate a value to visualize with opacity
valueExpression: "( $feature.TOT_VOTES / $feature.REG_VOTERS ) * 100",
stops: [
{ value: 30, opacity: 0.15 },
{ value: 70, opacity: 0.15 }
]
};
renderer.visualVariables = [ opacityVisualVariable ];
Constructors
-
Parameterproperties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Property Overview
Name | Type | Summary | Class |
---|---|---|---|
The name of the class. | Accessor | ||
The name of the numeric attribute field that contains the data values used to determine the color/opacity/size/rotation of each feature. | VisualVariable | ||
An object providing options for displaying the visual variable in the Legend. | VisualVariable | ||
Name of the numeric attribute field by which to normalize the data. | OpacityVariable | ||
An array of objects that defines the opacity to apply to features in a layer in a sequence of stops. | OpacityVariable | ||
The visual variable type. | OpacityVariable | ||
An Arcade expression following the specification defined by the Arcade Visualization Profile. | VisualVariable | ||
The title identifying and describing the associated Arcade expression as defined in the valueExpression property. | VisualVariable |
Property Details
-
field
InheritedPropertyfield String
Inherited from VisualVariable -
The name of the numeric attribute field that contains the data values used to determine the color/opacity/size/rotation of each feature.
-
Inherited from VisualVariable
-
An object providing options for displaying the visual variable in the Legend.
-
stops
stops OpacityStop[]autocast
-
An array of objects that defines the opacity to apply to features in a layer in a sequence of stops. You must specify 2 - 8 stops. In most cases, no more than five are needed. Features with data values that fall between the given stops will be assigned opacity values linearly interpolated along the ramp in relation to the stop values. The stops must be listed in ascending order based on the value of the
value
property in each stop.
-
type
type Stringreadonly
-
The visual variable type.
For OpacityVariable the type is always "opacity".
-
valueExpression
InheritedPropertyvalueExpression String
Inherited from VisualVariable -
An Arcade expression following the specification defined by the Arcade Visualization Profile. Expressions in visual variables may reference field values using the
$feature
profile variable and must return a number.The values returned from this expression are the data used to drive the visualization as defined in the stops. This takes precedence over field. Therefore, this property is typically used as an alternative to field in visual variables.
- See also
-
valueExpressionTitle
InheritedPropertyvalueExpressionTitle String
Inherited from VisualVariable -
The title identifying and describing the associated Arcade expression as defined in the valueExpression property. This is displayed as the title of the corresponding visual variable in the Legend in the absence of a provided
title
in the legendOptions property.
Method Overview
Name | Return Type | Summary | Class |
---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. | Accessor | ||
Creates a deep clone of the OpacityVariable. | OpacityVariable | ||
* | Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. | OpacityVariable | |
Returns true if a named group of handles exist. | Accessor | ||
Removes a group of handles owned by the object. | Accessor | ||
Converts an instance of this class to its ArcGIS portal JSON representation. | OpacityVariable |
Method Details
-
Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, addHandles added at 4.25. -
Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.
// Manually manage handles const handle = reactiveUtils.when( () => !view.updating, () => { wkidSelect.disabled = false; }, { once: true } ); this.addHandles(handle); // Destroy the object this.destroy();
ParametershandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
groupKey *optionalKey identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.
-
clone
clone(){OpacityVariable}
-
Creates a deep clone of the OpacityVariable.
ReturnsType Description OpacityVariable A deep clone of the opacity visual variable that invoked this method. Example// Creates a deep clone of the visual variable let renderer = renderer.visualVariables[0].clone();
-
Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. 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.Parameterjson ObjectA 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.
ReturnsType Description * Returns a new instance of this class.
-
hasHandles
InheritedMethodhasHandles(groupKey){Boolean}
Inherited from AccessorSince: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, hasHandles added at 4.25. -
Returns true if a named group of handles exist.
ParametergroupKey *optionalA group key.
ReturnsType Description Boolean Returns true
if a named group of handles exist.Example// Remove a named group of handles if they exist. if (obj.hasHandles("watch-view-updates")) { obj.removeHandles("watch-view-updates"); }
-
Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, removeHandles added at 4.25. -
Removes a group of handles owned by the object.
ParametergroupKey *optionalA group key or an array or collection of group keys to remove.
Exampleobj.removeHandles(); // removes handles from default group obj.removeHandles("handle-group"); obj.removeHandles("other-handle-group");
-
toJSON
toJSON(){Object}
-
Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.
ReturnsType Description Object The ArcGIS portal JSON representation of an instance of this class.