delayed_consumer_hud 0.1.0

HUD with delayed start using a provider as trigger

example/lib/main.dart

import 'package:delayed_consumer_hud/delayed_consumer_hud.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
        // This makes the visual density adapt to the platform that you run
        // the app on. For desktop platforms, the controls will be smaller and
        // closer together (more dense) than on mobile platforms.
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Delayed Consumer HUD example'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;
  final testViewModel = TestViewModel();

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

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    widget.testViewModel.isBusy = true;

    Future<void>.delayed(Duration(seconds: 5)).then((value) {
      setState(() {
        // This call to setState tells the Flutter framework that something has
        // changed in this State, which causes it to rerun the build method below
        // so that the display can reflect the updated values. If we changed
        // _counter without calling setState(), then the build method would not be
        // called again, and so nothing would appear to happen.
        _counter++;
        widget.testViewModel.isBusy = false;
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return ChangeNotifierProvider<TestViewModel>.value(
        value: widget.testViewModel,
        builder: (context, child) {
          return DelayedHud1<TestViewModel>(
            hud: CircularProgressIndicator(),
            showHud: (value1) {
              return value1.isBusy;
            },
            delayedStart: Duration(seconds: 1),
            child: Scaffold(
              appBar: AppBar(
                // Here we take the value from the MyHomePage object that was created by
                // the App.build method, and use it to set our appbar title.
                title: Text(widget.title),
              ),
              body: Center(
                // Center is a layout widget. It takes a single child and positions it
                // in the middle of the parent.
                child: Column(
                  // Column is also a layout widget. It takes a list of children and
                  // arranges them vertically. By default, it sizes itself to fit its
                  // children horizontally, and tries to be as tall as its parent.
                  //
                  // Invoke "debug painting" (press "p" in the console, choose the
                  // "Toggle Debug Paint" action from the Flutter Inspector in Android
                  // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
                  // to see the wireframe for each widget.
                  //
                  // Column has various properties to control how it sizes itself and
                  // how it positions its children. Here we use mainAxisAlignment to
                  // center the children vertically; the main axis here is the vertical
                  // axis because Columns are vertical (the cross axis would be
                  // horizontal).
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: <Widget>[
                    Text(
                      'You have pushed the button this many times:',
                    ),
                    Text(
                      '$_counter',
                      style: Theme.of(context).textTheme.headline4,
                    ),
                  ],
                ),
              ),
              floatingActionButton: FloatingActionButton(
                onPressed: _incrementCounter,
                tooltip: 'Increment',
                child: Icon(Icons.add),
              ), // This trailing comma makes auto-formatting nicer for build methods.
            ),
          );
        });
  }
}

class TestViewModel extends ChangeNotifier {
  bool _isBusy = false;

  set isBusy(bool value) {
    _isBusy = value;
    notifyListeners();
  }

  bool get isBusy {
    return _isBusy;
  }
}