react-native-form4u

A React Native form builder, simple, light and fast !

• Define fields using a simple json file. Any kind of react-native field or valid component is accepted;
• Define field validation with the flexibility of using a JavaScript function to return the erros;
• Define your own callback function to handle form submission;
• Package comes with a full Sign Up login screen example.

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Features

• Prevents submit dirty forms
• Initialize fields with default values
• Default mask types for most common field types, like datetime, only number, zip code, currency, Brazilian CPF/CNPJ
• Use custom masks with help of react-native-masked-text
• Supports custom validations
• Implements default validations for common field types (email)
• Define your own Form style
• Define your own Field style
• Uses Nativebase components

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Getting Started

• Installation
• Basic Usage
  • Fields
    • Field structure
  • Validation
  • Submit
• Field Types
  • boolean
  • button
  • reset
  • customComponent
  • text
  • email
  • credit-card
  • cpf
  • cnpj
  • zip-code
  • only-numbers
  • money
  • cel-phone
  • datetime
  • picker
• Properties
  • Form properties
  • Field properties
    • Custom masks
• Form example

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Installation

Install Peer Dependencies

The peer dependencies included from any npm packages does not automatically get installed. Your application will not depend on it explicitly.

react-native-form4u requires a peer of native-base

Install NativeBase

npm install native-base --save

Link the library

react-native link native-base

Icons

If you have icons problems, please try to install and link react-native-vector-icons

npm install --save react-native-vector-icon

react-native link react-native-vector-icons

Install Form4u

$ npm i react-native-form4u --save

Basic Usage

• Make sure you have react-native installed

npm i -g react-native

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Fields

see more

Field structure

Fields are array items. You can easily define more than one field per row. See example for more details.

Prop	Description	Default
name	Field name	None
label	Field label	None
required	Required field	false
type	Field type	Field Types
fieldProps	Default react props for each field type	None
defaultValue	Default value for the field	None
fieldStyle	Style object for the field	None
mask	Custom mask for the field	None

formFields = [
  [
    {
      name: "field1",
      label: "Field 1",
      required: false,
      type: "text",
      fieldProps: {},
      defaultValue: null,
      fieldStyle: {},
      mask: {}
    }
  ]
];

Example:

const fields = [
  [
    {
      name: "firstName",
      label: "First Name",
      type: "input",
      inputProps: {
        autoCorrect: false
      }
    },
    {
      name: "lastName",
      label: "Last Name",
      type: "input",
      inputProps: {
        autoCorrect: false
      }
    }
  ],
  [
    {
      name: "email",
      label: "Email",
      type: "input",
      inputProps: {
        autoCorrect: false,
        autoCapitalize: "none",
        keyboardType: "email-address"
      }
    }
  ],
  [
    {
      name: "subject",
      placeholder: "Pick a topic of your interest",
      pickerItems: [
        {
          label: "React Native",
          value: 0
        },
        {
          label: "React Hooks",
          value: 1
        },
        {
          label: "React Navigation",
          value: 2
        },
        {
          label: "React News",
          value: 3
        }
      ],
      type: "picker"
    }
  ],
  [
    {
      name: "password",
      label: "Password",
      type: "input",
      inputProps: {
        secureTextEntry: true
      }
    }
  ],
  [
    {
      name: "subscribe",
      label: "Subscribe me to weekly news from Tech world.",
      type: "boolean",
      defaultValue: true
    }
  ],
  [
    {
      name: "signUpButton",
      label: "Sign Up",
      type: "button"
    }
  ],
  [
    {
      name: "resetButton",
      label: "Reset",
      type: "button"
    }
  ]
];

Validation

see more

const validate = ({ firstName, lastName, email, subject, password }) => {
  const errors = {};
 
  if (!firstName.value) {
    errors.firstName = "First name is required";
  }
  if (!lastName.value) {
    errors.lastName = "Last name is required";
  }
 
  if (!email.value) {
    errors.email = "Email address is required";
  } else if (!/\S+@\S+\.\S+/.test(email.value)) {
    errors.email = "Email address is invalid";
  }
 
  if (!subject.value) {
    errors.subject = "A subject of interest is required.";
  }
 
  if (!password.value) {
    errors.password = "Password is required";
  }
 
  return errors;
};
 
export default validate;

Submit

see more

• this callback is executed after form submission/validation

const handleSubmit = fields => {
  const { firstName, lastName, email, subject, password } = fields;
 
  Alert.alert(
    "Your info",
    `First Name: ${firstName.value}\n Last Name: ${lastName.value}\n Email: ${
      email.value
    }\n Subject: ${subject.value} \n Password: ${password.value}`
  );
};

Field Types

boolean

button

reset

customComponent

text

email

credit-card

Field will be automatically formated according to card provider:

• visa or master: 9999 9999 9999 9999 or 9999 **** **** 9999 (obfuscated)
• amex: 9999 999999 99999 or 9999 ****** 99999 (obfuscated)
• diners: 9999 999999 9999 or 9999 ****** 9999 (obfuscated)

cpf

Field will be automatically formated for 999.999.999-99

cnpj

Field will be automatically formated for 99.999.999/9999-99

zip-code

Field will be automatically formated for 99999-999

only-numbers

accept only numbers

money

cel-phone

datetime

picker

Properties

Form properties

Any View property and the following:

Prop	Description	Default
formFields	Object with field definitions.	None
handleSubmit	Callback function to handle form submission	Inherited
validation	Function to return errors object	{fieldName: error message}
submitOnDirty	Disable form buttons in case form is dirty (empty or with errors)	false
formStyle	Style object with custom styles. Overrides default style of the Form	{flex:1 , padding: 10}

Field properties

Most style properties will work as expected.

Prop	Description	Default
size	Size of the icon, can also be passed as fontSize in the style object.	12
name	What icon to show, see Icon Explorer app or one of the links above.	None
color	Color of the icon.	Inherited

Custom masks

If you want, we use the MaskService from react-native-masked-text

Form example

see more

import Form4u from "react-native-form4u";
import fields from "./formFields.js";
import validationRules from "./formValidationRules.js";
 
const App = () => {
  return (
    <Form4u
      formFieldsRows={fields}
      handleSubmit={handleSubmit}
      validation={validationRules}
      submitOnDirty
    />
  );
};
 
export default App;

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BACKLOG

• Implement other field types
• Tests
• Documentation!!!

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Version History

0.0.1

• remove styled-component from Input from native-base, onChange and onChangeText were not been called see more
• fix errors view which was shrinking in few cases
• implement form validation with error messages
• Implement custom form picker
• Allows form to render any kind of React component
• Added react-native-maked-text to allows masked input texts

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Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

MIT