RunApp() 

Import 'package:flutter/material.dart';

void main() {
  runApp(
    Center(
      child: Text(
        'Hello, world!',
        textDirection: TextDirection.ltr,
      ),
    ),
  );
}
The widget tree consists of two widgets, the Center widget and its child, the Text widget.
The framework forces the root widget to cover the screen, which means the text “Hello, world” ends up centered on screen. The text direction needs to be specified in this instance; when the MaterialApp widget is used, this is taken care of for you, as demonstrated later.

Function that takes the given Widget and makes it the root of the widget tree.

Related concepts

→
RunApp()

RunApp() — Structure map

Clickable & Draggable!

RunApp() — Related pages:

Take a picture using the camera

Load sequence, performance, and memory

Introduction to widgets

Adding a Flutter Fragment to an Android app

Adding a Flutter screen to an Android app