onChange()

This event handler runs when a field value is changed.

Overview

This is a <Feathery.Form> prop and callback function to run custom logic when a field value is changed. It's called every time the user changes one or multiple field values. This function can be asynchronous.

Usage

You can use onChange to log or update form state when the user modifies it. It takes a single Context object that provides form-related state and handlers.

import { init, Form } from '@feathery/react';

function App() {
  // Initialize Feathery
  init('SDKKey', '[e-mail]');

  // Show the `aBcDeF` Feathery form
  return <Form
    formId='aBcDeF'
    // Custom form step onChange logic
    onChange={(context) => {
      if (context.trigger.id === 'is-it-birthday' && context.fields['is-it-birthday']) {
          showBirthdaySurprise();
      }
    }}
  />
}

Context API

Key	Type	Description
Form Context		Consistently available form state and functions
integrationData	optional object	Third-party metadata may be passed back through this property. If trigger equals addressSelect, this object returns the Google Places address ID (id), the components of its address, and the latitude / longitude of the address.
trigger	triggerData	Info of the element that triggered the field value change.
valueRepeatIndex	integer	Specifies which item (0-indexed) in the field value changed if there are multiple items. If an item was removed, the index will be -1.

integrationData Definition

If trigger equals addressSelect, this change event was triggered by the user selecting an Address Line 1 dropdown option. In that case, integrationData contains the address's Google Places address ID (id), its individual components, and the latitude / longitude.

triggerData Definition

Key	Type	Description
id	string	The ID of the field that changed.
type	enum {field, addressSelect}	What triggered the field value change. Either a form field was modified or an Address Line 1 autocomplete option was selected.
repeatIndex	integer	If the element whose value changed repeats, this specifies which repetition it is. This value is 0-indexed and equals 0 if the element doesn't repeat.