import 'package:flutter/material.dart'; extension TimeOfDayExt on TimeOfDay { bool isBefore(TimeOfDay other) => hour < other.hour && minute < other.minute; bool isAfter(TimeOfDay other) => hour > other.hour && minute > other.minute; TimeOfDay add({int hours = 0, int minutes = 0}) => replacing(hour: hour + hours, minute: minute + minutes); }