ICustomQuestionTypeConfiguration

createElements property

A function that allows you to create nested questions if you do not specify the elementsJSON property.

Type:: any readonly

Implemented in:: ICustomQuestionTypeConfiguration

See also:: elementsJSON

createQuestion property

A function that allows you to create a custom question if you do not specify the questionJSON property.

Type:: any readonly

Implemented in:: ICustomQuestionTypeConfiguration

See also:: questionJSON

defaultQuestionTitle property

A default title for questions created with this question type. Survey authors can change the default title in the JSON object or in Survey Creator's Property Grid.

You can specify the question title with a string value or with an object that defines different titles for different locales:

import { ComponentCollection } from "survey-core";

ComponentCollection.Instance.add({
  // ...
  defaultQuestionTitle: "Default title"
});
// ===== OR =====
ComponentCollection.Instance.add({
  // ...
  defaultQuestionTitle: {
    en: "Default title",
    de: "Standardtitel",
    fr: "Titre par défaut"
  }
});

Type:: any readonly

Implemented in:: ICustomQuestionTypeConfiguration

elementsJSON property

JSON schemas of nested questions. Specify this property to create a composite question type.

Type:: any readonly

Implemented in:: ICustomQuestionTypeConfiguration

getDisplayValue property

A function that allows you to override the default getDisplayValue() implementation.

Type:: ((keyAsText: boolean, value: any) => any) | ((question: Question) => any) readonly

Implemented in:: ICustomQuestionTypeConfiguration

getErrorText property

A function that allows you to display different error texts based on conditions.

Type:: (question: Question) => string readonly

Return Value:: An error text.

Implemented in:: ICustomQuestionTypeConfiguration

iconName property

The name of an icon to use for the custom question type.

UI Icons

Type:: string readonly

Implemented in:: ICustomQuestionTypeConfiguration

inheritBaseProps property

An array of property names to inherit from a base question or a Boolean value that specifies whether or not to inherit all properties.

Default value: false

When you create a custom specialized question type, you base it on another question type configured within the questionJSON object. If the custom question type should inherit all properties from the base type, set the inheritBaseProps property to true. If you want to inherit only certain properties, set the inheritBaseProps property to an array of their names.

Create Specialized Question Types

Type:: boolean | string[] readonly

Implemented in:: ICustomQuestionTypeConfiguration

name property

A name used to identify a custom question type.

Type:: string readonly

Implemented in:: ICustomQuestionTypeConfiguration

See also:: title

onAfterRender method

A function that is called after the entire question is rendered.

Parameters:

question: Question
A custom question.
htmlElement: any
An HTML element that represents the custom question.

Type:: (question: Question, htmlElement: any) => void

Parameters:: question, type: Question

htmlElement, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onAfterRenderContentElement method

A function that is called each time a question nested within a composite question is rendered.

Parameters:

question: Question
A composite question.
element: Question
A nested question.
htmlElement: any
An HTML element that represents a nested question.

Type:: (question: Question, element: Question, htmlElement: any) => void

Parameters:: question, type: Question

element, type: Question

htmlElement, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onCreated method

A function that is called when the custom question is created. Use it to access questions nested within a composite question type.

Parameters:

question: Question
The custom question.

Type:: (question: Question) => void

Parameters:: question, type: Question

Implemented in:: ICustomQuestionTypeConfiguration

onInit method

A function that is called when the custom question type is initialized. Use it to add, remove, or modify the type's properties (see Override Base Question Properties).

Type:: () => void

Implemented in:: ICustomQuestionTypeConfiguration

onItemValuePropertyChanged method

A function that is called when an ItemValue property is changed.

Parameters:

question: Question
A custom question.
options.obj: ItemValue
An ItemValue object.
options.propertyName: string
The name of the property to which an array of ItemValue objects is assigned (for example, "choices" or "rows").
options.name: string
The name of the changed property: "text" or "value".
options.newValue: any
A new value for the property.

Type:: (question: Question, options: { obj: ItemValue; propertyName: string; name: string; newValue: any; }) => void

Parameters:: question, type: Question

options, type: { obj: ItemValue; propertyName: string; name: string; newValue: any; }

Implemented in:: ICustomQuestionTypeConfiguration

onLoaded method

A function that is called when JSON schemas are loaded.

Parameters:

question: Question
A custom question.

Type:: (question: Question) => void

Parameters:: question, type: Question

Implemented in:: ICustomQuestionTypeConfiguration

onPropertyChanged method

A function that is called when a custom question type property is changed. Use it to handle property changes.

Parameters:

question: Question
A custom question.
propertyName: string
The name of the changed property.
newValue: any
A new value for the property.

Type:: (question: Question, propertyName: string, newValue: any) => void

Parameters:: question, type: Question

propertyName, type: string

newValue, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onUpdateQuestionCssClasses method

A function that is called each time a question nested within a composite question requires an update of its CSS classes.

Parameters:

question: Question
A composite question.
element: Question
A nested question.
cssClasses: any
An object with CSS classes applied to a nested question, for example, { root: "class1", button: "class2" }. You can modify this object to apply custom CSS classes.

Type:: (question: Question, element: Question, cssClasses: any) => void

Parameters:: question, type: Question

element, type: Question

cssClasses, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onValueChanged method

A function that is called after the question value is changed in the UI.

Parameters:

question: Question
A custom question.
name: string
The question's name.
newValue: any
A new value for the question.

If you want to perform some actions when the value is changed in code as well as in the UI, implement the onValueSet function.

Type:: (question: Question, name: string, newValue: any) => void

Parameters:: question, type: Question

name, type: string

newValue, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onValueChanging method

A function that is called before a question value is changed in the UI.

This function should return the value you want to save: newValue, a custom value, or undefined if you want to clear the question value.

Parameters:

question: Question
A custom question.
name: string
The question's name.
newValue: any
A new value for the question.

Type:: (question: Question, name: string, newValue: any) => any

Parameters:: question, type: Question

name, type: string

newValue, type: any

Implemented in:: ICustomQuestionTypeConfiguration

onValueSet property

A function that is called after the question value is set.

Parameters:

question: Question
A custom question.
newValue: any
A new value for the question.

Unlike the onValueChanged function, which is called only when the question value is changed in the UI, onValueSet is called when the value is changed in code as well.

View Demo