import 'package:flutter/material.dart'; class FingerprintText extends StatelessWidget { const FingerprintText(this.longString, {super.key}); final String longString; String formatString(String input) { final formattedString = StringBuffer(); var blockCount = 0; for (var i = 0; i < input.length; i += 4) { final block = input.substring(i, i + 4 > input.length ? input.length : i + 4); formattedString.write(block); blockCount++; if (blockCount == 5) { formattedString.writeln(); blockCount = 0; } else { formattedString.write(' '); } } return formattedString.toString().trim(); } @override Widget build(BuildContext context) { return SelectableText( formatString(longString), style: const TextStyle(fontSize: 16, color: Colors.black), textAlign: TextAlign.center, ); } }