The ExpressionInfo
class references Arcade expressions following
the specification defined by the Arcade Popup Profile.
Expressions must return a string or a number and may access data values from the feature, its layer, or other layers
in the map or datastore with the $feature
, $layer
, $map
, and $datastore
profile variables.
Expression names are referenced in a layer's PopupTemplate and execute once a layer's popup is opened. The values display within the view's popup as if they are field values. They can be displayed in a table using the FieldInfo of the popupTemplate's content or referenced within a simple string.
- See also
// Display a table in the popup's content referencing two values
// one from a field, and another returned from an Arcade expression
layer.popupTemplate = {
title: "Population in {NAME}",
content: [{
type: "fields",
fieldInfos: [{
fieldName: "POP_2015",
label: "Total population (2015)",
format: {
digitSeparator: true
}
}, {
fieldName: "expression/per-asian"
}]
}]
};
Constructors
-
new ExpressionInfo(properties)
-
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 |
---|---|---|---|
String | The name of the class. more details | Accessor | |
String | An Arcade expression following the specification defined by the Arcade Popup Profile. more details | ExpressionInfo | |
String | The name of the expression. more details | ExpressionInfo | |
String | Indicates the return type of the Arcade expression. more details | ExpressionInfo | |
String | The title used to describe the value returned by the expression in the popup. more details | ExpressionInfo |
Property Details
-
The name of the class. The declared class name is formatted as
esri.folder.className
.
-
expression String
-
An Arcade expression following the specification defined by the Arcade Popup Profile. Expressions must return a string or a number and may access data values from the feature, its layer, or other layers in the map or datastore with the
$feature
,$layer
,$map
, and$datastore
profile variables.Example// Calculates the percentage of the population that is Asian expressionInfo.expression = "Text($feature.Asian / $feature.TOT_POP, '#.#%')";
-
name String
-
The name of the expression. This is used to reference the value of the given
expression
in the popupTemplate's content property by wrapping it in curly braces and prefacing it withexpression/
(e.g.{expression/expressionName}
).ExampleexpressionInfo.name = "percent-asian";
-
returnType String
-
Indicates the return type of the Arcade expression.
Possible Values:"string"|"number"
-
title String
-
The title used to describe the value returned by the expression in the popup. This will display if the value is referenced in a FieldInfo table.
ExampleexpressionInfo.title = "Percent Asian";
Method Overview
Name | Return Type | Summary | Class |
---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. more details | Accessor | ||
ExpressionInfo | Creates a deep clone of the ExpressionInfo class. more details | ExpressionInfo | |
* | Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. more details | ExpressionInfo | |
Boolean | Returns true if a named group of handles exist. more details | Accessor | |
Removes a group of handles owned by the object. more details | Accessor | ||
Object | Converts an instance of this class to its ArcGIS portal JSON representation. more details | ExpressionInfo |
Method Details
-
addHandles(handleOrHandles, groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 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(){ExpressionInfo}
-
Creates a deep clone of the ExpressionInfo class.
ReturnsType Description ExpressionInfo A deep clone of the ExpressionInfo instance.
-
fromJSON(json){*}static
-
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.
-
Since: ArcGIS Maps SDK for JavaScript 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"); }
-
removeHandles(groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 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(){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.