an_lifecycle_hooks - Dart API docs

A toolkit that introduces lifecycle events from the AnLifecycle library into the hooks library

Usage

1.1 Prepare the lifecycle environment.


class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    // Use LifecycleApp to wrap the default App
    return LifecycleApp(
      child: MaterialApp(
        title: 'Lifecycle Hook Demo',
        theme: ThemeData(
          primarySwatch: Colors.blue,
        ),
        navigatorObservers: [
          //Use LifecycleNavigatorObserver.hookMode() to register routing event changes
          LifecycleNavigatorObserver.hookMode(),
        ],
        home: const MyHomePage(title: 'Lifecycle Hook Home Page'),
      ),
    );
  }
}

The current usage of PageView and TabBarViewPageView should be replaced with LifecyclePageView and LifecycleTabBarView. Alternatively, you can wrap the items with LifecyclePageViewItem. You can refer to anlifecycle for guidance.

1.2 Use useLifecycle useLifecycleEffect


class HomeService {
  final ValueNotifier<int> stayed = ValueNotifier<int>(0);

  void startTicker(Lifecycle lifecycle) {
    // 在可见的时间 每秒增加1  不可见时不增加
    Stream.periodic(const Duration(seconds: 1))
        .bindLifecycle(lifecycle, repeatLastOnStateAtLeast: true)
        .listen((event) => stayed.value += 1);
  }
}

class HomeServiceDemo extends HookWidget {
  const HomeServiceDemo({super.key});

  @override
  Widget build(BuildContext context) {
    // 单独使用lifecycle
    final homeService = useLifecycleEffect<HomeService>(
      factory: HomeService.new,
      // 在首次可见时启动
      launchOnFirstResume: (l, service) => service.startTicker(l),
    );
    // hooks 处理变化
    final stayed = useListenable(homeService.stayed);

    return Scaffold(
      appBar: AppBar(
        title: Text('Lifecycle Hook Demo Home Page'),
      ),
      body: Center(
        child: Text(
          'Stayed on this page for:${stayed.value} s',
        ),
      ),
    );
  }
}


class HomeViewModel with ViewModel {
  // 获取存放全局配置 需要已经存在或者提前已经注册过创建方式 ViewModel.factories
  //    .addFactory(AppViewModel.new, producer: ViewModel.producer.byApp);
  late final AppViewModel appModel = viewModels();

  // 创建一个自动管理的 ValueNotifier<int>
  late final counter = valueNotifier(0);

  void incrementCounter() {
    counter.value += appModel.incrementStep;
  }
}

class HomeViewModelDemo extends HookWidget {
  const HomeViewModelDemo({super.key});

  @override
  Widget build(BuildContext context) {
    // 使用viewmodel
    final viewModel = useLifecycleViewModelEffect(factory: HomeViewModel.new);

    // hooks 处理变化
    final counter = useListenable(viewModel.counter);

    return Scaffold(
      appBar: AppBar(
        title: Text('ViewModel Hook Demo Home Page'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '${counter.value}',
              style: Theme
                  .of(context)
                  .textTheme
                  .headlineMedium,
            ),
          ],
        ),
      ),
      floatingActionButton: const HomeFloatingButton(),
    );
  }
}

/// 模拟这是另一个widget 需要使用MyHomePage中的同一个ViewModel
class HomeFloatingButton extends HookWidget {
  const HomeFloatingButton({super.key});

  @override
  Widget build(BuildContext context) {
    // 如果提前已经注册过或者确定已经存在对象则可以直接使用
    final vm = useLifecycleViewModelEffect<HomeViewModel>();
    return FloatingActionButton(
      onPressed: vm.incrementCounter,
      tooltip: 'Increment',
      child: const Icon(Icons.add),
    );
  }
}