FieldElement | References | ArcGIS Maps SDK for JavaScript

import FieldElement from "@arcgis/core/form/elements/FieldElement.js";

Inheritance:: FieldElement→Element→Accessor

Since: ArcGIS Maps SDK for JavaScript 4.16

A FieldElement form element defines how a feature layer's Field participates in the FeatureForm. Use this approach to set field configurations within a feature form or feature layer formTemplate.

form template field elements

See also

Example

// Create the field element
const fieldElement1 = new FieldElement({
  fieldName: "inspector",
  label: "Inspector name"
});

const fieldElement2 = new FieldElement({
  fieldName: "inspdate",
  label: "Inspection date",
  description: "Date inspection was handled",
  input: { // autocastable to DatePickerInput
    type: "date-picker",
      min: "2010-01-15",
      max: "2030-01-15"
    }
});

const fieldElement3 = new FieldElement({
  fieldName: "placename",
  label: "Business name",
  editableExpression: "editing-disabled"
});

const fieldElement4 = new FieldElement({
  fieldName: "floodinsur",
  label: "Flood insurance",
  input: { // autocastable to RadioButtonsInput
    type: "radio-buttons",
    noValueOptionLabel: "Not applicable",
    showNoValueOption: true
  }
});

// Next pass in any elements to the FormTemplate
const formTemplate = new FormTemplate({
  title: "Inspector report",
  description: "Enter all relevant information below",
  expressionInfos: [{
    name: "editing-disabled",
    expression: "false",
    returnType: "boolean"
  }],
  elements: [fieldElement1, fieldElement2, fieldElement3, fieldElement4] // Add all elements to the template
});

Constructors

Constructor

Parameters

Parameter	Type	Description	Required
properties	`FieldElementProperties`

See the properties table for a list of all the properties that may be passed into the constructor.

Properties

Any properties can be set, retrieved or listened to. See the Watch for changes topic.

Property	Type	Class
`declaredClass` readonly inherited	`string`	Accessor
`description` inherited	`string \| null \| undefined`	Element
`domain`	`CodedValueDomain \| RangeDomain \| null \| undefined`
`editableExpression`	`string \| null \| undefined`
`fieldName`	`string \| null \| undefined`
`hint`	`string \| null \| undefined`
`input`	`Input \| null \| undefined`
`label` inherited	`string \| null \| undefined`	Element
`requiredExpression`	`string \| null \| undefined`
`type` readonly	`"field"`
`valueExpression`	`string \| null \| undefined`
`visibilityExpression` inherited	`string \| null \| undefined`	Element

declaredClass

readonlyinherited Property

Type: string

Inherited from: Accessor

The name of the class. The declared class name is formatted as esri.folder.className.

description

inherited Property

Type: string | null | undefined

Inherited from: Element

The element's description providing the purpose behind it.

domain

autocast Property

Type: CodedValueDomain | RangeDomain | null | undefined

The coded value domain or range domain of the field.

editableExpression

Property

Type: string | null | undefined

Since: ArcGIS Maps SDK for JavaScript 4.23

A reference to the ExpressionInfo.name of an Arcade expression defined in the FormTemplate.expressionInfos of the FormTemplate.

When this expression evaluates to true, it is possible to edit the field value, and vice-versa if false. If the referenced field on the feature service is not editable, the editable expression is ignored and the element is not editable.

The expression must follow the specification defined in the Form Constraint Profile. Expressions may reference field values using the $feature global input and must return either true or false. It is required to set the FeatureForm.map property when instantiating a FeatureForm widget and using expressions that make use of the $map variable. Editing must be disabled if setting a field element's valueExpression. The referenced expression must be defined in the form template's FormTemplate.expressionInfos. It cannot be set inline within the element object.

See also

fieldName

Property

Type: string | null | undefined

The field name as defined by the feature layer. Set this property to indicate which field to edit.

hint

Property

Type: string | null | undefined

Contains a hint used to help editors while editing fields. Set this as a temporary placeholder for text/number inputs in either TextAreaInput or TextBoxInput.

input

autocast Property

Type: Input | null | undefined

The input to use for the element. The client application is responsible for defining the default user interface.

label

inherited Property

Type: string | null | undefined

Inherited from: Element

A string value containing the field alias. This should not be used for referencing fields in Arcade expressions. Rather, the service FieldElement.fieldName should be referenced.

requiredExpression

Property

Type: string | null | undefined

A reference to the ExpressionInfo.name of an Arcade expression defined in the FormTemplate.expressionInfos of the FormTemplate. An expression that evaluates to true results in the field element requiring the end user to provide a value for fieldName for the feature to be created or edited. If the expression evaluates to false, the end user is not required to provide a value to the element.

If the referenced fieldName is non-nullable, the requiredExpression is ignored and the element is always required.

The expression must follow the specification defined in the Form Constraint Profile. Expressions may reference field values using the $feature global input and must return either true or false. It is required to set the FeatureForm.map property when instantiating a FeatureForm widget and using expressions that make use of the $map variable. The referenced expression must be defined in the form template's FormTemplate.expressionInfos. It cannot be set inline to this property. Field and Group elements must be visible if the field or one of the grouped fields is required.

See also

Form Constraint Arcade Profile

Examples

// The diameter field requires a value to be created or edited
// if the inspectionStatus value is "Complete"
// if the status is not complete, then this field value is optional
const dbhFieldElement = new FieldElement({
  fieldName: "diameter",
  input: {
    type: "text-box"
  },
  requiredExpression: "tree-dbh",
  editableExpression: "editable"
});

layer.formTemplate = new FormTemplate({
  elements: [ dbhFieldElement ],
  expressionInfos: [{
    expression: "$feature.inspectionStatus == 'Complete'",
    name: "tree-dbh",
    title: "Tree DBH",
    returnType: "boolean"
  }, {
    expression: "true",
    name: "editable",
    returnType: "boolean"
  }]
});

// The field value will ALWAYS be required when editing with a form
const dbhFieldElement = new FieldElement({
  editable: true,
  fieldName: "diameter",
  input: {
    type: "text-box"
  },
  requiredExpression: "always-required",
  editableExpression: "editable"
});

layer.formTemplate = new FormTemplate({
  elements: [ dbhFieldElement ],
  expressionInfos: [{
    // An expression that always returns true
    expression: "true",
    name: "always-required",
    returnType: "boolean"
  }, {
    expression: "true",
    name: "editable",
    returnType: "boolean"
  }]
});

type

readonly Property

Type: "field"

Indicates the type of form Element.

valueExpression

Property

Type: string | null | undefined

Since: ArcGIS Maps SDK for JavaScript 4.23

A reference to the ExpressionInfo.name of an Arcade expression defined in the FormTemplate.expressionInfos of the FormTemplate.

Once the expression evaluates, the form's field value updates to the expression's result.

The expression must follow the specification defined in the Form Calculation Profile. This expression references field values within an individual feature or in other layers and must return either a date, number, or string value. Editing must be disabled, which may be done via the editableExpression. The referenced expression must be defined in the form template's FormTemplate.expressionInfos. It cannot be set inline within the element object.

See also

Example

// Calculates the diameter based on the circumference field
const dbhFieldElement = new FieldElement({
  fieldName: "diameter",
  input: {
    type: "text-box"
  },
  valueExpression: "tree-dbh",
  // element must not be editable to enable valueExpression
  editableExpression: "not-editable"
});

layer.formTemplate = new FormTemplate({
  elements: [ dbhFieldElement ],
  expressionInfos: [{
    expression: "Round(DefaultValue($feature.circumference, 0) / PI, 1)",
    name: "tree-dbh",
    title: "Tree DBH",
    returnType: "boolean"
  }, {
    expression: "false",
    name: "not-editable",
    returnType: "boolean"
  }]
});

visibilityExpression

inherited Property

Type: string | null | undefined

Inherited from: Element

A reference to the ExpressionInfo.name of an Arcade expression defined in the FormTemplate.expressionInfos of the FormTemplate.

When this expression evaluates to true, the element is displayed. When the expression evaluates to false the element is not displayed. If no expression is provided, the element is always displayed. Care must be taken when defining a visibility expression for a non-nullable field as to make certain the specified field has either 1) a default value, or 2) is made visible to the end user to enter a value before submitting the form.

The expression must follow the specification defined in the Form Calculation Profile. This expression references field values within an individual feature or in other layers and must return either a date, number, or string value. The referenced expression must be defined in the form template's FormTemplate.expressionInfos. It cannot be set inline within the element object. Field and Group elements must be visible if the field or one of the grouped fields is required.

See also

Example

// Expression created within ExpressionInfos and is referenced in element
const expression = new ExpressionInfo({
  name: "alwaysHidden",
  expression: "false"
});

// Reference an already-defined visibilityExpression set within the ExpressionInfos
const fieldElement = new FieldElement({
  type: "field",
  fieldName: "inspemail",
  label: "Email address",
  visibilityExpression: "alwaysHidden"
});

formTemplate.expressionInfos = [ expression ];
formTemplate.elements = [ fieldElement ];

Methods

Method	Signature	Class
`fromJSON` inherited static	`fromJSON(json: any): any`	JSONSupportMixin
`clone`	`clone(): FieldElement`
`toJSON` inherited	`toJSON(): any`	JSONSupportMixin

fromJSON

inheritedstatic Method

Signature: fromJSON (json: any): any

Inherited from: JSONSupportMixin

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.

Parameters

Parameter	Type	Description	Required
json	`any`	A 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.

Returns: any
Returns a new instance of this class.

clone

Method

Signature: clone (): FieldElement

Creates a deep clone of the FieldElement class.

Returns: FieldElement
A deep clone of the FieldElement instance.

toJSON

inherited Method

Signature: toJSON (): any

Inherited from: JSONSupportMixin

Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.

Returns: any
The ArcGIS portal JSON representation of an instance of this class.