timbergus

import 'package:flutter/material.dart';

class Login extends StatefulWidget {
  @override
  _LoginState createState() => _LoginState();
}

class _LoginState extends State<Login> {
  String _email;
  String _password;

timbergus

import 'package:flutter/material.dart';
import 'package:flutter_app/login.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(

timbergus

import React, { Component, createRef } from 'react';

export default class CMP extends Component {
  constructor(props) {
    super(props);
    this.refA = createRef();
    this.refB = createRef();
  }
  
  render() {

timbergus

final _loginFormKey = GlobalKey<FormState>();

// This method call the functions in our component's
// validator property.

_loginFormKey.currentState.validate();

// This method call the functions in our component's
// onSaved method.

timbergus

final _loginFormKey = GlobalKey<FormState>();

// This method call the functions in our component's
// validator property.

_loginFormKey.currentState.validate();

// This method call the functions in our component's
// onSaved method.

timbergus

TextFormField(
  validator: (val) {
    if (val.isEmpty) {
      return 'You must enter a valid email!';
    }
    return null;
  },
  onSaved: (val) => _email = val,
),

timbergus

RaisedButton(
  child: Text('Login'),
  onPressed: () {
    if (_loginFormKey.currentState.validate()) {
      _loginFormKey.currentState.save();
      print('Email: $_email, password: $_password');
    }
  },
),

timbergus

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'My Weather App',
      home: MyHomePage(),

timbergus

import 'package:geolocator/geolocator.dart';

class _MyHomePageState extends State<MyHomePage> {
  
  [...]
  
  Future<Position> getPosition() async {
    Position position = await Geolocator()
      .getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
    return position;

timbergus

import 'package:geolocator/geolocator.dart';

class _MyHomePageState extends State<MyHomePage> {
  
  [...]
  
  String _locality = '';
  
  Future<Placemark> getPlacemark(double latitude, double longitude) async {
    List<Placemark> placemark = await Geolocator()