“runApp()” and “main()” functions in Flutter?

In Flutter, the runApp() and main() functions are essential for building and running applications.

The main() function is the entry point of every Dart application, including Flutter applications. In a Flutter application, the main() function typically calls the runApp() function, which initializes the Flutter framework and runs the application.

The runApp() function is responsible for creating a Flutter App widget and attaching it to the device screen. This function takes an argument of a Widget object that represents the root of the application’s widget tree. The Widget object is usually an instance of the MaterialApp or CupertinoApp widget, which are pre-built widgets that provide common design patterns for Material Design and Cupertino (iOS) style apps respectively.

Here is an example of how main() and runApp() functions are used in a Flutter application:

In the above example, the main() function calls the runApp() function with an instance of the MyApp widget as an argument. The MyApp widget is defined as a stateless widget that returns a MaterialApp widget as its child. The MaterialApp widget provides a basic Material Design scaffold that displays a title bar and a centered text widget that displays the text “Hello, World!”.