info_tren/lib/main.dart

import 'package:flutter/material.dart';

import 'models/train_data.dart';
import 'train_info_display.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Info Tren',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        brightness: Brightness.dark,
        primaryColor: Colors.blue.shade600,
        accentColor: Colors.blue.shade700,
      ),
      home: MainPageWrapper(),
    );
  }
}

class MainPageWrapper extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return TrainDataSourceWidget(
      child: MainPage()
    );
  }
}

class MainPage extends StatefulWidget {
  @override
  _MainPageState createState() => _MainPageState();
}

class _MainPageState extends State<MainPage> {
  final trainNumberController = TextEditingController();
  bool showAlternate = false;

  bool get shouldTap {
    return trainNumberController.text.isNotEmpty;
  }

  onTap(BuildContext context) {
    FocusScope.of(context).requestFocus(FocusNode());
    TrainDataSourceWidget.of(context).lookup(trainNumberController.text, showAlternate);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Info Tren"),
        centerTitle: true,
        actions: <Widget>[
          IconButton(
            icon: Icon(Icons.settings),
            onPressed: () {
              showModalBottomSheet(context: context, builder: (context) {
                return StatefulBuilder(
                  builder: (context, ssSheet) =>
                    SafeArea(
                      bottom: true,
                      top: false,
                      left: true,
                      right: true,
                      child: Column(
                        mainAxisSize: MainAxisSize.min,
                        children: <Widget>[
                          ListTile(
                            title: Text(
                              showAlternate
                                ? "Afișează rezultatul principal"
                                : "Afișează rezultatul alternativ"
                            ),
                            onTap: () {
                              showAlternate = !showAlternate;
                              setState(() {});
                              ssSheet(() {});
                            },
                          )
                        ],
                      ),
                    ),
                );
              });
            },
          )
        ],
      ),
      body: Column(
        children: <Widget>[
          Row(
            children: <Widget>[
              Expanded(
                child: Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: TextField(
                    controller: trainNumberController,
                    onChanged: (_) => setState(() => {}),
                    autofocus: true,
                    decoration: InputDecoration(
                      labelText: "Numărul trenului",
                      border: OutlineInputBorder(),
                      hintText: "Scrieți doar numărul"
                    ),
                    onSubmitted: (_) {
                      if (shouldTap) {
                        onTap(context);
                      }
                    },
                    keyboardType: TextInputType.numberWithOptions(),
                    textInputAction: TextInputAction.search,
                  ),
                ),
              ),
              Padding(
                padding: const EdgeInsets.all(8.0),
                child: RaisedButton(
                  child: Text("Caută"),
                  onPressed: (() {
                    if (!shouldTap) return null;
                    return () {
                      onTap(context);
                    };
                  })(),
                ),
              )
            ],
          ),
          Text(
            showAlternate
              ? "Se va afișa rezultatul alternativ\nla următoarea căutare"
              : "Se va afișa rezultatul principal\nla următoarea căutare",
            style: Theme.of(context).textTheme.caption.copyWith(fontStyle: FontStyle.italic),
            textAlign: TextAlign.center,
          ),
          Divider(
            color: Theme.of(context).accentColor,
            height: 4,
          ),
          Expanded(
            child: Padding(
              padding: const EdgeInsets.all(8.0),
              child: TrainInfoDisplay(),
            ),
          )
        ],
      ),
    );
  }
}

class TrainInfoDisplay extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return StreamBuilder<TrainDataEvent>(
      stream: TrainDataSourceWidget.of(context).dataStream,
      builder: (context, snapshot) {
        if (snapshot.connectionState != ConnectionState.active) {
          return Container();
        }

        if (snapshot.hasError) {
          final error = snapshot.error as TrainDataEvent;

          if (error.kind == TrainDataEventKind.NOT_FOUND) {
            return Center(
              child: Text(
                "Train number ${error.trainNumber}\nwas not found!",
                style: Theme.of(context).textTheme.headline,
                textAlign: TextAlign.center,
              )
            );
          }

          if (error.kind == TrainDataEventKind.TIMEOUT) {
            return Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: <Widget>[
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: Text(
                      "The request has timed out!",
                      style: Theme.of(context).textTheme.headline,
                      textAlign: TextAlign.center,
                    ),
                  ),
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: RaisedButton(
                      child: Text("Retry"),
                      onPressed: () {
                        TrainDataSourceWidget.of(context).lookup(error.trainNumber);
                      },
                    ),
                  )
                ],
              )
            );
          }

          if (error.kind == TrainDataEventKind.UNKNOWN_ERROR) {
            return Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: <Widget>[
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: Text("An unknown error with the status code ${error.errorStatusCode} has occured."),
                  ),
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: RaisedButton(
                      child: Text("Retry"),
                      onPressed: () {
                        TrainDataSourceWidget.of(context).lookup(error.trainNumber);
                      },
                    ),
                  )
                ],
              ),
            );
          }
        }

        if (snapshot.hasData) {
          if (snapshot.data.kind == TrainDataEventKind.LOADING) {
            return Center(
              child: CircularProgressIndicator(),
            );
          }

          if (snapshot.data.kind == TrainDataEventKind.GOT_DATA) {
            return TrainInfoDisplayData(snapshot.data.trainData);
          }
        }

        return Placeholder();
      },
    );
  }
}