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🏁 React Final Form Arrays

Installation

npm install --save react-final-form-arrays react-final-form final-form final-form-arrays

yarn add react-final-form-arrays react-final-form final-form final-form-arrays

Usage

🏁 React Final Form Arrays provides a way to render arrays in 🏁 React Final Form.

import { Form, Field } from 'react-final-form'
import arrayMutators from 'final-form-arrays'
import { FieldArray } from 'react-final-form-arrays'

const MyForm = () => (
  <Form
    onSubmit={onSubmit}
    mutators={{
      // potentially other mutators could be merged here
      ...arrayMutators
    }}
    validate={validate}
    render={({ handleSubmit, pristine, invalid }) => (
      <form onSubmit={handleSubmit}>
        <FieldArray name="customers">
          {({ fields }) => (
            <div>
              {fields.map((name, index) => (
                <div key={name}>
                  <div>
                    <label>First Name</label>
                    <Field name={`${name}.firstName`} component="input" />
                  </div>
                  <div>
                    <label>Last Name</label>
                    <Field name={`${name}.lastName`} component="input" />
                  </div>
                  <button type="button" onClick={() => fields.remove(index)}>
                    Remove
                  </button>
                </div>
              ))}
              <button
                type="button"
                onClick={() => fields.push({ firstName: '', lastName: '' })}
              >
                Add
              </button>
            </div>
          )}
        </FieldArray>
      </form>
    )}
  />
)

Examples
- Simple Example
- React Beautiful DnD Example
Rendering
API
Types
- FieldArrayProps
- FieldArrayRenderProps

Examples

Simple Example

Demostrates how to use <FieldArray/> to render an array of inputs, as well as use push, pop, and remove mutations.

React Beautiful DnD Example

Demostrates how to integrate the simple example with react-beautiful-dnd

Rendering

There are three ways to tell <FieldArray/> what to render:

Method	How it is rendered
`component` prop	`return React.createElement(this.props.component, props)`
`render` prop	`return this.props.render(props)`
a render function as `children`	`return this.props.children(props)`

API

The following can be imported from react-final-form-arrays.

`FieldArray : React.ComponentType<FieldArrayProps>`

A component that takes FieldArrayProps and renders an array of fields

The useFieldArray hook takes two parameters, the first is the name of the field, and the second is an optional object that looks just like FieldArrayProps, except without the name. It returns an object just like FieldArrayRenderProps.

useFieldArray is used interally inside FieldArray.

`version: string`

The current used version of 🏁 React Final Form Arrays.

Types

`FieldArrayProps`

These are props that you pass to <FieldArray/>. You must provide one of the ways to render: component, render, or children.

`children?: ((props: FieldArrayRenderProps) => React.Node) | React.Node`

A render function that is given FieldArrayRenderProps, as well as any non-API props passed into the <FieldArray/> component.

`component?: React.ComponentType<FieldArrayRenderProps>`

A component that is given FieldArrayRenderProps as props, as well as any non-API props passed into the <FieldArray/> component.

`name: string`

The name of your field array.

`render?: (props: FieldArrayRenderProps) => React.Node`

A render function that is given FieldArrayRenderProps, as well as any non-API props passed into the <FieldArray/> component.

`defaultValue?: any`

⚠️ You probably want initialValue! ⚠️

Before using this prop, read and understand the 🏁 Final Form documentation on initialValue and defaultValue!

`initialValue?: any`

See the 🏁 Final Form docs on initialValue

`isEqual?: (allPreviousValues: Array<any>, allNewValues: Array<any>) => boolean`

A function that can be used to compare two arrays of values (before and after every change) and calculate pristine/dirty checks. Defaults to a function that will === check each element of the array.

`subscription?: FieldSubscription`

A FieldSubscription that selects of all the items of FieldState that you wish to update for. If you don't pass a subscription prop, it defaults to all of FieldState.

`validate?: (value: ?any[], allValues: Object) => ?any`

A function that takes the field value, and all the values of the form and returns an error if the array value is invalid, or undefined if the value is valid.

`FieldArrayRenderProps`

These are the props that <FieldArray/> provides to your render function or component. This object is divided into a fields object that mimics an iterable (e.g. it has map() and forEach() and length), and meta data about the field array. Keep in mind that the values in meta are dependent on you having subscribed to them with the subscription prop

`fields.forEach: (iterator: (name: string, index: number) => void) => void`

Iterates through all of the names of the fields in the field array in bracket format, e.g. foo[0], foo[1], foo[2].

`fields.insert: (index: number, value: any) => void`

A function to insert a value into any arbitrary index of the array.

`fields.map: (iterator: (name: string, index: number) => any) => any[]`

Iterates through all of the names of the fields in the field array in bracket format, e.g. foo[0], foo[1], foo[2], and collects the results of the iterator function. You will use this in almost every implementation.