formatEditUpdate method

TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue)

Called when text is being typed or cut/copy/pasted in the EditableText.

You can override the resulting text based on the previous text value and the incoming new text value.

When formatters are chained, oldValue reflects the initial value of TextEditingValue at the beginning of the chain.

Implementation

TextEditingValue formatEditUpdate(
    TextEditingValue oldValue, TextEditingValue newValue) {
  if (newValue.selection.baseOffset == 0) {
    return newValue;
  }

  if (newValue.selection.baseOffset > maxDigits) {
    return oldValue;
  }

  double value = double.parse(newValue.text);
  final formatter = new NumberFormat("#,##0.00", "pt_BR");
  String newText = "R\$ " + formatter.format(value / 100);
  return newValue.copyWith(
      text: newText,
      selection: new TextSelection.collapsed(offset: newText.length));
}