Flutter abstract class

Yes, you can define a class inside an interface . In general, if the methods of the interface use this class and if we are not using it anywhere else we will declare a class within an interface.

In order to make a variable or function private to a class, the name of the variable or function needs to start with underscore( _ ) . Variables/function without underscore( _ ) are public. You have defined a private function and accessing the private function.

Dart does not have any separate syntax to define interfaces. An Interface defines the same as the class where any set of methods can be accessed by an object. The Class declaration can interface itself. The keyword implement is needed to be writing, followed by class name to be able to use the interface.

Dart has no interface keyword. Instead, all classes implicitly define an interface . Therefore, you can implement any class.

An interface is declared by using the interface keyword . It provides total abstraction; means all the methods in an interface are declared with the empty body, and all the fields are public, static and final by default. A class that implements an interface must implement all the methods declared in the interface.