React Native Currency Input

A simple currency input component for both IOS and Android.

The goal of react-native-currency-input is to offer a simple and effective way to handle number inputs with custom format, usually a currency input case, but it can actually be used for other purposes.

React-Native-Currency-Input

Features

  • A simple and practical component for number inputs (read currency input)
  • It's just a <TextInput/> component, so you can use its props and it's easy to customize
  • Set precision, delimiter, separator and unit so you can actually have any number format you want
  • It handles negative values, in addition to having a prop to disable it
  • Set minimun and maximum value
  • Use React Native ES6 and React Hooks

BONUS

Installation

npm install react-native-currency-input

or

yarn add react-native-currency-input

Usage

import CurrencyInput from 'react-native-currency-input';

function MyComponent() {
  const [value, setValue] = React.useState(2310.458); // can also be null

  return (
    <CurrencyInput
      value={value}
      onChangeValue={setValue}
      unit="$"
      delimiter=","
      separator="."
      precision={2}
      onChangeText={(formattedValue) => {
        console.log(formattedValue); // $2,310.46
      }}
    />
  );
}

Props

This component uses the same props as <TextInput/>. Below are the additional props for this component:

Prop Type Default Description
value number The value for controlled input. REQUIRED
onChangeValue function Callback that is called when the input's value changes. REQUIRED
unit string Character to be prefixed on the value.
delimiter string , Character for thousands delimiter.
separator string . Decimal separator character.
precision number 2 Decimal precision.
ignoreNegative boolean false Set this to true to disable negative values.
maxValue number Max value allowed. This might cause unexpected behavior if you pass a value higher than this direct to the input.
minValue number Min value allowed. This might cause unexpected behavior if you pass a value lower than this direct to the input.
onChangeText function Callback that is called when the input's text changes. IMPORTANT: This does not control the input value, you should use onChangeValue.

Example

See EXAMPLE

git clone https://github.com/caioquirinomedeiros/react-native-currency-input.git
cd react-native-currency-input/example
yarn
yarn android / yarn ios

FakeCurrencyInput

This component hides the real currency input and use a Text to imitate the input, so you won't get the flickering issue but will lost the selection functionality. The cursor is not a real cursor, but a pipe character (|) that will be always at the end of the text. It also have a wrapper View with position 'relative' on which the Text Input is stretched over.

  • Pros
    • No flickering issue as a controlled input component
    • The cursor is locked at the end, avoiding the user to mess up with the mask
  • Cons
    • Lost of selection functionality... The user will still be able to copy/paste, but with a bad experience
    • The cursor is locked at the end... You may have users who won't like that

FakeCurrencyInput Usage

import { FakeCurrencyInput } from 'react-native-currency-input';

function MyComponent() {
  const [value, setValue] = ReactuseState(0); // can also be null

  return (
    <FakeCurrencyInput
      value={value}
      onChangeValue={setValue}
      unit="$"
      delimiter=","
      separator="."
      precision={2}
      onChangeText={(formattedValue) => {
        // ...
      }}
    />
  );
}

FakeCurrencyInput Props

It includes the same props of the CurrencyInput with the additional of the following:

Prop Type Default Description
containerStyle style prop Style for the container View that wraps the Text.
caretColor string #6495ed Color of the caret.

formatNumber(value, options)

import { formatNumber } from 'react-native-currency-input';

const value = -2375923.3;

const formattedValue = formatNumber(value, {
  separator: ',',
  unit: 'R$ ',
  precision: 2,
  delimiter: '.',
  ignoreNegative: true,
});

console.log(formattedValue); // R$ 2.375.923,30

options (optional)

Name Type Default Description
unit string Character to be prefixed on the value.
delimiter string , Character for thousands delimiter.
separator string . Decimal separator character.
precision number 2 Decimal precision.
ignoreNegative boolean false Set this to true to disable negative values.

GitHub