Lifecycle Flutter

 ///Note: As flutter is open-source, we can check the code and change it according to our needs.

///Stages Of App Lifecycle:
// The life cycle depends on the state and how it changes.
// A stateful widget has a state so we can clarify the life cycle of flutter dependent on it. Stage of the life cycle:
//
// createState()
//
// initState()
//
// didChangeDependencies()
//
// build()
//
// didUpdateWidget()
//
// setState()
//
// deactivate()
//
// dispose()

///Life Cycle of Flutter Widgets
///Stateless Widgets: The widgets which remain constant throughout the lifetime of the app are called stateless widgets.
// We use them when we want structures to stay the same all over the app, for example, the AppBar, color scheme,
// i.e. generally the User Interface(UI). These widgets are immutable, i.e. they cannot be changed.
// Here Hot Reload can reflect the changes made in the app structure and can be used for verification.
//
// Stateless widgets are just like a single block widget that cannot be planned.
// They can only be destroyed to create a new one with another set of widget configuration and properties.
//
// The life cycle of stateless widgets is simple; there’s only one stage: the build method.
// As soon as the widget gets built, the build method gets automatically called where you are supposed to create
// whatever appearance you want to add up in your application.
/// class MainPage extends StatelessWidget {
///  @override
///  Widget build(BuildContext context) {
///    return null;
///  }
/// }

///StatefulWidget lifecycle
//When a Flutter builds a StatefulWidget, it creates a State object.
// This object is where all the mutable state for that widget is held.
//
/// The concept of state is defined by two things:
//1. The data used by the widget might change.
//2. The data can't be read synchronously when the widget is built.
// (All state must be established by the time the build method is called).
//
/// The lifecycle has the following simplified steps:
//
// createState()
// mounted == true
// initState()
// didChangeDependencies()
// build()
// didUpdateWidget()
// setState()
// deactivate()
// dispose()
// mounted == false


///Architecture of flutter
// The flutter framework is a layered system with each layer dependent on the layer below.
// A single layer has several independent libraries.
/// On a high level, the flutter framework’s architecture has three main parts or layers:
// Embedder
// Engine
// Framework

///Framework layer :
// Foundation layer,
// Rendering layer,
// Widget layer

///A widget tree of "Hello world" :
// Root
// MaterialApp
// Homepage
// Scaffold: AppBar : Text
//           Center : Text



//Architecture overview
// lifecycle -> app, stateful & stateless
// platform adaptations