Installation:
yarn add react-native-simple-code-input

Usage:
import PinCode from 'react-native-simple-code-input';

<PinCode
    onFulFill={value => alert('value', value)}
    length={8}
/>

ClearCode:

<PinCode
    ref={ref => this.pincode = ref}
    onFulFill={value => alert('value', value)}
    length={8}
/>

this.pincode.clearCode();

Customize Code Component:

<PinCode
    ref={ref => this.pincode = ref }
    onFulFill={value => console.log('input value', value)}
    length={8}
    onChangeText={value => console.log('input value', value)}
    keyboardType='numeric'
    cuztomize
    renderValueComponent={value => <Text red>{value}</Text>}
    renderEmptyComponent={value => <Text red>x</Text>}
/>  

<Text onPress={() => this.pincode && this.pincode.clearCode()}>Clear</Text>