Reimplementation of flutter StatelessWidget to get direct lifecycle methods on stateless widgets

life_cycle_stateless_widget.dart

import 'package:flutter/material.dart' as material;

class StatelessElement extends material.StatelessElement {
  StatelessElement(
    super.widget, {
    this.onCreate,
    this.onDispose,
    this.afterBuild,
    this.afterCreate,
  });

  final void Function()? onCreate;
  final void Function()? onDispose;
  final void Function()? afterBuild;
  final void Function()? afterCreate;

  @override
  void unmount() {
    _runLifecycleCallback(onDispose);
    super.unmount();
  }

  @override
  void mount(material.Element? parent, Object? newSlot) {
    _runLifecycleCallback(onCreate);
    super.mount(parent, newSlot);
  }

  @override
  material.Widget build() {
    _runLifecycleCallback(afterCreate);
    final widget = super.build();
    _runLifecycleCallback(afterBuild);
    return widget;
  }

  void _runLifecycleCallback(Function()? callback) {
    if (callback is Function) {
      callback!();
    }
  }
}

/// StatelesWidget reimplementation to get a lifecycle methods for Widgets
///
/// - onCreate - Called when Stateless Widget is instantiated
/// - afterCreate - Called after the complete creation of StatelessWidget and before build()
/// - afterBuild - Called immediately after StatelessWidget build()
/// - onDispose - Called when the StatelessWidget is unmounted
///
/// Example:
/// ```
///   class MyWidget extends StatelessWidget {
///
///     @override
///     void onCreate() {
///       print('My widget has been instantiated');
///     }
///
///     @override
///     void afterCreate() {
///       print('My widget has been instantiated and will be able to build()');
///     }
///
///     @override
///     void afterBuild() {
///       print('My widget was builded by build() method');
///     }
///
///     @override
///     void onDispose() {
///       print('My widget was unmounted');
///     }
/// 
///     @override
///     Widget build(BuildContext context) {
///       return Center(
///         child: Text('MyWidget'),
///       );
///     }
///   }
/// ```
///
abstract class StatelessWidget extends material.StatelessWidget {
  const StatelessWidget({super.key});

  @override
  material.StatelessElement createElement() {
    return StatelessElement(
      this,
      onCreate: onCreate,
      onDispose: onDispose,
      afterBuild: afterBuild,
      afterCreate: afterCreate,
    );
  }

  /// onCreate is called immediately after instantiating a StatelessWidget
  @material.protected
  void onCreate() {}

  /// afterCreate is called after the StatelessWidget has completed initialization but before the build() starts
  @material.protected
  void afterCreate() {}

  /// afterBuild is called immediately after StatelessWidget build()
  @material.protected
  void afterBuild() {}

  /// onDispose is called when the StatelessWidget is unmounted
  @material.protected
  void onDispose() {}
}