Enter number in reverse order in text field

I have a TextInput in react-native , I want to enter a number in order as 0.00 => 0.01 => 0.12 => 1.23 => 12.34 => 123.45 like this on each change text . CSS Direction “rtl” is not working . Looking for an algorithm to apply in my JS file for react-native textInput on

onChangeText={(amount) => this.onChangeText(amount)}

 onChangeText = (amount) => {
    //. Logic for reverse goes here

    this.setState({
      amount: newAmount,
      amountError: false,
    });
  };