Mis Flutteris vastab puu hierarhiale?

In Flutter, the hierarchy of the tree is represented by the Widget Tree. Each interface element is a widget, which can contain other widgets, forming a nested structure.

This widget tree describes the UI structure, and Flutter uses it to build and update the interface. Besides the widget tree, there are also element trees (Element Tree) and render object trees (Render Object Tree), which are responsible for lifecycle and rendering respectively, but the main hierarchy is exactly the widget tree.

Example of a simple widget tree:

Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(title: Text('Example')), // AppBar is a child widget of Scaffold
    body: Center(
      child: Column(
        children: [
          Text('Hello'),
          ElevatedButton(onPressed: () {}, child: Text('Press')),
        ],
      ),
    ),
  );
}