Getters and setters IN DART

Getters and setters

Getter and setter methods provide read and write access to internal object state. When calling a getter or setter, omit the trailing parentheses. Define getters and setters using the getand set keywords.

class Rectangle {
  num left, top, width, height;

  Rectangle(this.left, this.top, this.width, this.height);

  num get right()           => left + width;
      set right(num value)  => left = value - width;
  num get bottom()          => top + height;
      set bottom(num value) => top = value - height;
}

Use explicit getters and setters just like you would use the generated getters and setters from instance variables.

var rect = new Rectangle(3, 4, 20, 15);
assert(rect.left == 3);
rect.right = 12;
assert(rect.left == -8);

With getters and setters, you can start with instance variables, later wrapping them with methods, all without changing client code