how to subtract two different times in flutter - flutter

Question

I want to subtract two different times in flutter for example
String time1 = "07:00";
String time2 = "08:12";
String time3 = time2 - time1;
//result will be 01:12
this is just a sample data explanation of what I want to achieve.

Answer 1

See the sample code below. It prints 01:12 in the end.
Input Data:
String time1 = "07:00";
String time2 = "08:12";
Required Methods to be defined:
DateTime getTime(final String inputString) => DateFormat("hh:mm").parse(inputString);
String getString(final Duration duration) {
String formatDigits(int n) => n.toString().padLeft(2, '0');
final String minutes = formatDigits(duration.inMinutes.remainder(60));
return "${formatDigits(duration.inHours)}:$minutes";
}
Computation
final String difference = getString(getTime(time2).difference(getTime(time1)));
Printing the result
print(difference); // 01:12
Have fun - but keep in mind to change the naming of the methods to better fit into your context.

Answer 2

You should use Dart's built-in DateTime class and its DateTime.parse especially.
Documentation: https://api.dart.dev/stable/2.8.4/dart-core/DateTime/parse.html

Answer 3

Try out below code for get difference between two times.
var timeFormat = DateFormat("HH:mm"); //Time format
var first = timeFormat.parse("10:40");
var second = timeFormat.parse("18:20");
print("Difference -->${second.difference(first)}");
// prints Difference -->7:40

Answer 4

Flutter|Dart provides a data type to handle dates : DateTime. So instead of using String, use DateTime :
DateTime time1 = DateTime.parse(your_date_here your_time);
DateTime time2 = DateTime.parse(your_date_here your_time);
DateTime time3 = time2.difference(time1);
If you want just the time part, you can format it using DateFormat from the intl package. You'll need to import it as follows :
import 'package:intl/intl.dart';
Then do the following:
String formattedTime = DateFormat.Hms().format(time1);
String formattedTime = DateFormat.Hms().format(time2);
Or you can just directly format the result (time3):
String formattedTime = DateFormat.Hms().format(time3);