Flutter插件excalibur的使用_excalibur是一个用于以简洁的方式处理异常的Flutter包

Excalibur介绍

一个用于以简洁的方式处理异常的Flutter包。

Flutter插件excalibur的使用

导入包

import 'package:excalibur/excalibur.dart';

定义自定义异常

通过扩展BladeException类来定义您的自定义异常。

class CustomException implements BladeException {
  // 异常的错误码
  @override
  int get code => 1;

  // 显示给用户的错误信息
  @override
  String get message => '自定义异常消息';

  // 是否替换当前页面
  @override
  bool get replace => false;
}

初始化并使用Excalibur

void main() {
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});
  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  late Excalibur excalibur;
  final _exceptions = [
    CustomException(), // 注册自定义异常
  ];

  void _incrementCounter() {
    setState(() {
      _counter++;
      try {
        // 触发自定义异常
        throw CustomException();
      } catch (e) {
        excalibur.handleException(e as BladeException);
      }
    });
  }

  @override
  void initState() {
    // 初始化Excalibur实例
    excalibur = Excalibur(
      context,
      exceptions: _exceptions,
      unknownException: UnknownNumberException(), // 未知异常
      builder: (exception) => ErrorPage(exception: exception), // 错误页面构建器
    );
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              '你已经按了按钮多少次：',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: '增加',
        child: const Icon(Icons.add),
      ),
    );
  }
}

// 自定义异常页面
class ErrorPage extends StatelessWidget {
  final BladeException exception;

  const ErrorPage({Key? key, required this.exception}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(exception.code.toString()),
      ),
      body: Center(
        child: Text(exception.message),
      ),
    );
  }
}

// 未知异常
class UnknownNumberException implements BladeException {
  @override
  int get code => 2;

  @override
  String get message => '未知数字异常';

  @override
  bool get replace => false;
}

抛出异常

throw CustomException();

或者通过Excalibur实例抛出：

excalibur.throwException(1);