import 'package:flutter/material.dart'; class StringUtils { static String capitalizeFirstLetter(String text) { if (text.isEmpty) return text; return text[0].toUpperCase() + text.substring(1); } } bool isEndTimeAfterStartTime(TimeOfDay start, TimeOfDay end) { final startMinutes = start.hour * 60 + start.minute; final endMinutes = end.hour * 60 + end.minute; if (endMinutes <= startMinutes) { return true; } return false; } String formatTimeOfDayTo24HourString(TimeOfDay time) { final hour = time.hour.toString().padLeft(2, '0'); final minute = time.minute.toString().padLeft(2, '0'); return '$hour:$minute'; }