flutter-vienna-hackathon-25/wien_talks/wien_talks_flutter/lib/main.dart

import 'package:flutter/material.dart';
import 'package:serverpod_flutter/serverpod_flutter.dart';
import 'package:wien_talks_client/wien_talks_client.dart';
import 'package:wien_talks_flutter/go_router.dart';

/// Sets up a global client object that can be used to talk to the server from
/// anywhere in our app. The client is generated from your server code
/// and is set up to connect to a Serverpod running on a local server on
/// the default port. You will need to modify this to connect to staging or
/// production servers.
/// In a larger app, you may want to use the dependency injection of your choice
/// instead of using a global client object. This is just a simple example.
late final Client client;

late String serverUrl;

void main() {
  // When you are running the app on a physical device, you need to set the
  // server URL to the IP address of your computer. You can find the IP
  // address by running `ipconfig` on Windows or `ifconfig` on Mac/Linux.
  // You can set the variable when running or building your app like this:
  // E.g. `flutter run --dart-define=SERVER_URL=https://api.example.com/`
  const serverUrlFromEnv = String.fromEnvironment('SERVER_URL');
  final serverUrl = serverUrlFromEnv.isEmpty ? 'http://$localhost:8080/' : serverUrlFromEnv;

  client = Client(serverUrl)..connectivityMonitor = FlutterConnectivityMonitor();

  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
      title: 'Serverpod Demo',
      theme: ThemeData(primarySwatch: Colors.blue),
      routerConfig: router,
      //home: NewsScreen(),
      //home: const MyHomePage(title: 'Serverpod Example'),
    );
  }
}

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

  final String title;

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

class MyHomePageState extends State<MyHomePage> {
  /// Holds the last result or null if no result exists yet.
  String? _resultMessage;

  /// Holds the last error message that we've received from the server or null
  /// if no error exists yet.
  String? _errorMessage;

  final _textEditingController = TextEditingController();

  /// Calls the `hello` method of the `greeting` endpoint. Will set either the
  /// `_resultMessage` or `_errorMessage` field, depending on if the call
  /// is successful.
  void _callHello() async {
    try {
      final result = await client.greeting.hello(_textEditingController.text);
      setState(() {
        _errorMessage = null;
        _resultMessage = result.message;
      });
    } catch (e) {
      setState(() {
        _errorMessage = '$e';
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          children: [
            Padding(
              padding: const EdgeInsets.only(bottom: 16.0),
              child: TextField(
                controller: _textEditingController,
                decoration: const InputDecoration(hintText: 'Enter your name'),
              ),
            ),
            Padding(
              padding: const EdgeInsets.only(bottom: 16.0),
              child: ElevatedButton(
                onPressed: _callHello,
                child: const Text('Send to Server'),
              ),
            ),
            ResultDisplay(
              resultMessage: _resultMessage,
              errorMessage: _errorMessage,
            ),
          ],
        ),
      ),
    );
  }
}

/// ResultDisplays shows the result of the call. Either the returned result
/// from the `example.greeting` endpoint method or an error message.
class ResultDisplay extends StatelessWidget {
  final String? resultMessage;
  final String? errorMessage;

  const ResultDisplay({super.key, this.resultMessage, this.errorMessage});

  @override
  Widget build(BuildContext context) {
    String text;
    Color backgroundColor;
    if (errorMessage != null) {
      backgroundColor = Colors.red[300]!;
      text = errorMessage!;
    } else if (resultMessage != null) {
      backgroundColor = Colors.green[300]!;
      text = resultMessage!;
    } else {
      backgroundColor = Colors.grey[300]!;
      text = 'No server response yet.';
    }

    return ConstrainedBox(
      constraints: const BoxConstraints(minHeight: 50),
      child: Container(
        color: backgroundColor,
        child: Center(child: Text(text)),
      ),
    );
  }
}