/Dart/Dart set final variable in constructor

Dart set final variable in constructor

// You cannot mutate final variables in a constructor body, 
// instead you must use a special syntax.
// Also note if you have a super() call, it must be called last.
class Point {
  final num x;
  final num y;
  final num distanceFromOrigin;

  // Special syntax
  Point(this.x, this.y) :
    distanceFromOrigin = sqrt(pow(x, 2) + pow(y, 2));
}

Source: stackoverflow.com

Similar codes

1 vote329 views1 answer
Flutter tooltip circle border
Dart
1 vote296 views1 answer
Flutter array of strings
Dart
1 vote311 views1 answer
Flutter pretext on textfield
Dart
8 votes308 views1 answer
Listview inside column flutter
Dart
27 votes465 views1 answer
Flutter turn string to int
Dart
0 vote317 views1 answer
Dart add String item to list
Dart
4 votes315 views1 answer
Flutter rotatedbox
Dart
21 votes335 views6 answers
FirebaseException ([core/no-app] No Firebase App '[DEFAULT]' has been created - call Firebase.initializeApp())
Dart
4 votes329 views3 answers
Flutter get key from map
Dart
1 vote362 views2 answers
How to put tapping effect on card in flutter
Dart