Programming Flutter

Classes

Classes in Dart work a lot like classes in other object-oriented languages, but here’s most of what you need to know to get started.

Members: Properties and Methods

Properties are variables declared as members of a class:

class User {
  int id;
  String username;
  String password;
}

Methods are functions defined inside classes. They are defined just like top-level functions, but inside the body of a class definition:

class User {
  int id;
  String username;
  String password;

  void setId(int newId) {
    id = newId;
  }
}

Accessing Members: Dot Notation

Members can be accessed using dot notation. If you wanted to get the id property of the user object and assign it to the a variable, you’d write:

var a ...