/Dart/Dart he default constructor is already defined. Try giving one of the constructors a name.

Dart he default constructor is already defined. Try giving one of the constructors a name.

In dart you can not have the same method/constructor name used several times 
(even with different parameters).

In your case you can either use named constructor to define 2 constructors :

class FirstClass {
  FirstClass() {}
  FirstClass.withA(a) {}
}

Source: stackoverflow.com

Similar codes

3 votes186 views1 answer
Android studio avd crashing
Dart
0 vote194 views1 answer
Options != null "FirebaseOptions cannot be null when creating the default app."
Dart
9 votes147 views2 answers
Update dart sdk command
Dart
1 vote189 views1 answer
Flutter tooltip height
Dart
0 vote223 views1 answer
How to delete a specific item from dart
Dart
1 vote184 views1 answer
Dart set list spread operator
Dart
6 votes178 views2 answers
Flutter flotingactionbutton
Dart
1 vote181 views1 answer
Ink image clip flutter
Dart
17 votes195 views4 answers
Cannot run with sound null safety because the following dependencies don't support null safety
Dart
3 votes196 views3 answers
Print flutter objects
Dart