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, but it can be used for any number input case.

• Features
• Installation
• Basic Usage
• Advanced Usage
• Using custom TextInput
• Props
• Example
• FakeCurrencyInput
  • FakeCurrencyInput Usage
  • FakeCurrencyInput Props
• formatNumber
  • formatNumber Options

Features

• A simple and practical component for number inputs
• It's just a <TextInput/> component, so you can use its props and it's easy to customize
• Handle any number format with these powerful props: precision, delimiter, separator, prefix and suffix.
• It handles negative values and you can choose the position of the sign with the signPosition.
• Set minimun and maximum values with minValue and maxValue.
• Use React Native ES6 and React Hooks

BONUS

• <FakeCurrencyInput />: A fake input that hides the real TextInput in order to get rid of the flickering issue
• formatNumber(): A function that formats number

Installation

npm install react-native-currency-input

or

yarn add react-native-currency-input

Basic 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} />;
}

Advanced Usage

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

function MyComponent() {
  const [value, setValue] = React.useState(2310.458);

  return (
    <CurrencyInput
      value={value}
      onChangeValue={setValue}
      prefix="R$"
      delimiter="."
      separator=","
      precision={2}
      minValue={0}
      showPositiveSign
      onChangeText={(formattedValue) => {
        console.log(formattedValue); // R$ +2.310,46
      }}
    />
  );
}

Using custom TextInput

import CurrencyInput from 'react-native-currency-input';
import { Input } from 'native-base';

function MyComponent() {
  const [value, setValue] = React.useState(2310.458);

  return (
    <CurrencyInput
      value={value}
      onChangeValue={setValue}
      renderTextInput={textInputProps => <Input {...textInputProps} variant='filled' />}
      renderText
      prefix="R$"
      delimiter="."
      separator=","
      precision={2}
    />
  );
}

Props

| Prop | Type | Default | Description | | ---------------------- | -------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | | ...TextInputProps | | | Inherit all props of TextInput. | | value | number | | The value for controlled input. REQUIRED | | onChangeValue | function | | Callback that is called when the input's value changes. REQUIRED | | prefix | string | | Character to be prefixed on the value. | | suffix* | string | | Character to be suffixed on the value. | | delimiter | string | , | Character for thousands delimiter. | | separator | string | . | Decimal separator character. | | precision | number | 2 | Decimal precision. | | maxValue | number | | Max value allowed. Might cause unexpected behavior if you pass a value higher than the one defined here. | | minValue | number | | Min value allowed. Might cause unexpected behavior if you pass a value lower than the one defined here. | | signPosition | string | "afterPrefix" | Where the negative/positive sign (+/-) should be placed. | | showPositiveSign | boolean | false | Set this to true to show the + character on positive values. | | onChangeText | function | | Callback that is called when the input's text changes. IMPORTANT: This does not control the input value, you must use onChangeValue. | | renderTextInput | function | | Use a custom TextInput component. |

* IMPORTANT: Be aware that using the suffix implies setting the selection property of the TextInput internally. You can override the selection, but that will cause behavior problems on the component

Tip: If you don't want negative values, just use minValue={0}.

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 TextInput and use a Text on its place, so you'll lost the cursor, but will get rid of the flickering issue. To replace the cursor it's used 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 TextInput 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...

FakeCurrencyInput Usage

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

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

  return (
    <FakeCurrencyInput
      value={value}
      onChangeValue={setValue}
      prefix="$"
      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 | | ------------------------- | ---------- | ------- | ------------------------------------------------- | | ...CurrencuInputProps | | | Inherit all props of CurrencyInput. | | 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: ',',
  prefix: 'R$ ',
  precision: 2,
  delimiter: '.',
  signPosition: 'beforePrefix',
});

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

options (optional)

| Name | Type | Default | Description | | ---------------------- | ------- | ------------- | ---------------------------------------------------------------- | | prefix | string | | Character to be prefixed on the value. | | suffix | string | | Character to be suffixed 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. | | signPosition | string | "afterPrefix" | Where the negative/positive sign (+/-) should be placed. | | showPositiveSign | boolean | false | Set this to true to show the + character on positive values. |

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

License

react-native-currency-input is released under the MIT license. See LICENSE for details.

Any question or support will welcome.