flutter 1.5 in action

https://flutter.dev/docs/get-started/flutter-for/react-native-devs

https://flutter.dev/docs/get-started/flutter-for/web-devs

open ios simulator from terminal

# simulator

$ open -a Simulator

https://flutter.dev/docs/get-started/install/macos#set-up-the-ios-simulator

run ios simulator in spotlight

https://stackoverflow.com/questions/10379622/how-to-run-iphone-emulator-without-starting-xcode

https://facebook.github.io/react-native/docs/running-on-simulator-ios

https://itnext.io/you-dont-need-gui-or-how-to-control-ios-simulator-from-command-line-bf5cfa60aed2

https://developer.apple.com/library/archive/documentation/IDEs/Conceptual/iOS_Simulator_Guide/GettingStartedwithiOSSimulator/GettingStartedwithiOSSimulator.html

run

https://flutter.dev/docs/get-started/test-drive?tab=terminal#run-the-app-2

# Check that an Android device is running

$ flutter devices

$ flutter run

$ flutter devices

$ flutter run -d all

env

https://flutter.dev/docs/get-started/install/macos#update-your-path

$ which .zshrc

$ which flutter

#  edit $HOME/.zshrc

$ cat $HOME/.zshrc

$ vim $HOME/.zshrc

$ code .  $HOME/.zshrc

export PATH="$PATH:[PATH_TO_FLUTTER_GIT_DIRECTORY]/flutter/bin"

export PATH=/usr/local/mongodb/bin:$PATH

1.2.1

import 'package:flutter/material.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,

      ),

      home: MyHomePage(title: 'Flutter Demo Home Page'),

    );

  }

}

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;

  @override

  _MyHomePageState createState() => _MyHomePageState();

}

class _MyHomePageState extends State<MyHomePage> {

  int _counter = 0;

  void _incrementCounter() {

    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++;

    });

  }

  @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 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 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.display1,

            ),

          ],

        ),

      ),

      floatingActionButton: FloatingActionButton(

        onPressed: _incrementCounter,

        tooltip: 'Increment',

        child: Icon(Icons.add),

      ), // This trailing comma makes auto-formatting nicer for build methods.

    );

  }

}

1.5.4 install

https://flutter.dev/docs/get-started/install/macos

upgrade

https://flutter.dev/docs/development/tools/sdk/upgrading

$ flutter channel

$ flutter upgrade

# stable, beta, dev, and master

$ flutter channel stable

$ flutter upgrade

https://github.com/flutter/flutter/tree/master/examples

https://github.com/flutter/flutter/blob/master/examples/hello_world/lib/main.dart

delete old & rename new

Flutter versions

flutter_macos_v1.2.1-stable.zip & 464 MB

2019.03.16

flutter_macos_v1.5.4-hotfix.2-stable.zip & 576 MB

2019.06.16

Stable channel

Select from the following scrollable list



Version    Ref    Release Date

v1.5.4-hotfix.2    7a4c334    5/8/2019

v1.2.1    8661d8a    2/27/2019

v1.0.0    5391447    12/5/2018

demo

// Copyright 2019 xgqfrms

import 'package:flutter/widgets.dart';

void main() => runApp(const Center(child: Text('Hello, world!', textDirection: TextDirection.ltr)));