package_exception_handler 0.3.0

Flutter package for exception handling within custom packages.

example/lib/main.dart

// Copyright (c) 2019, the EOMarch project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:flutter/material.dart';

import 'package:package_exception_handler/package_exception_handler.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  final navigatorKey = GlobalKey<NavigatorState>();
  final scaffoldKey = GlobalKey<ScaffoldState>();

  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> with ErrorStream {
  var stackTrace = '';

  @override
  void initState() {
    initErrorStream(); // To be sure that after disposing Stream will be initialized again
    error.listen((data) {
      widget.scaffoldKey.currentState.showSnackBar(SnackBar(
        duration: const Duration(seconds: 3),
        content: Text(data.currentError.toString()), // Gets current Error or Exception
        action: SnackBarAction(
          label: 'Stack Trace',
          onPressed: () => setState(() => stackTrace = data.stackTrace
              ?.toString()), // Gets stack trace, if it have been provided
        ),
      ));
    });
    super.initState();
  }

  @override
  void dispose() {
    disposeErrorStream(); // Need to dispose error to prevent memory leaks
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      navigatorKey: widget.navigatorKey,
      home: Scaffold(
        key: widget.scaffoldKey,
        appBar: AppBar(
          title: const Text('Pkg Exception Handler Example App'),
        ),
        body: Center(
          child: FractionallySizedBox(
            widthFactor: 0.75,
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.stretch,
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                RaisedButton(
                  onPressed: () {
                    // Handles sync error if retutn type is void or it doesn't matter
                    handleError(() {
                      // do stuff that might fail
                      throw AssertionError();
                    });
                  },
                  child: Text('Generate Error'),
                ),
                SizedBox(height: 25),
                RaisedButton(
                  onPressed: () {
                    // Handles async error if retutn type is void or it doesn't matter
                    handleErrorAsync(Future.delayed(const Duration(seconds: 2))
                        .whenComplete(() => throw FormatException()));
                  },
                  child: Text('Generate Async Error'),
                ),
                SizedBox(height: 25),
                RaisedButton(
                  onPressed: () {
                    // Handle error on your own using recordError method within catch statement
                    try {
                      // do stuff that might fail
                      throw UnsupportedError('test error');
                    } catch (e, stackTrace) {
                      recordError(e,
                          stackTrace); // Add Error or Exception (with StackTrace) to stream
                      return false;
                    }
                  },
                  child: Text('Generate Error with Raw Handling'),
                ),
                SizedBox(height: 50),
                InkResponse(
                  onTap: () => setState(() => stackTrace = ''),
                  child: Text(stackTrace),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}