import 'package:flutter/widgets.dart';
import 'package:get/get.dart';

class ReactiveController extends GetxController {
  Widget? _cachedView;

  Widget render(Widget Function() build) {
    if (_cachedView != null) {
      return _cachedView!;
    } else {
      _cachedView = build();
      return _cachedView!;
    }
  }
}

abstract class ReactiveState<T extends StatefulWidget> extends State<T> {
  Widget? _cachedView;

  @override
  void initState() {
    super.initState();
    receiveProps();
  }

  @override
  void didUpdateWidget(T oldWidget) {
    super.didUpdateWidget(oldWidget);
    receiveProps();
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    // 此处必须重建组件，防止更新字体或者夜间模式切换时组件不刷新
    _cachedView = null;
  }

  void receiveProps() {}

  Widget render(BuildContext context) {
    throw Exception("Render is not impleted");
  }

  @override
  Widget build(BuildContext context) {
    if (_cachedView != null) {
      return _cachedView!;
    } else {
      _cachedView = render(context);
      return _cachedView!;
    }
  }
}