Introducing login screen (zachran-jidlo#2)

* Add gradle signing configuration

* Add login screen frontend

* Introduce constants

* Extracting button to custom widget.

* Change button color.

* Extract text field to custom widget.

* Fix overflowing problem on login screen.

* Extract clickable text to custom widget.

* Introducing checkbox to remember user on login screen

* Changing text field style

* Adding simple home screen, provider and routing

* Adding simple login form validation

* Introducing newUser method in user model and unsetting user credentials after logout

* Commenting out wrapper for now

* Adding form validation error message to constants

* Fixing typo in a file name

* Introducing wrapper which checks whether the user is already logged in.

Co-authored-by: Jakub Timko <[email protected]>

lib/constants.dart

@@ -0,0 +1,18 @@
+import 'package:flutter/material.dart';
+
+class ZachranObedColors {
+  static const primary = Color.fromRGBO(226, 16, 19, 1);
+  static const primaryLight = Color.fromRGBO(250, 71, 71, 1);
+}
+
+class ZachranObedStrings {
+  static const emailAddress = 'E-mailová adresa';
+  static const password = 'Heslo';
+  static const login = 'Přihlásit se';
+  static const forgottenPassword = 'Zapomněl/a jsem heslo';
+  static const rememberUser = 'Zapamatovat';
+  static const requiredFieldError = 'Vyplňte prosím toto pole';
+
+  static const zjLogoPath = 'assets/zj-logo.svg';
+  static const placeholderImagePath = 'assets/placeholder-image.png';
+}

lib/main.dart

@@ -1,115 +1,26 @@
-import 'package:flutter/material.dart';
-
-void main() {
-  runApp(const MyApp());
-}
-
-class MyApp extends StatelessWidget {
-  const MyApp({super.key});
-
-  // 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: const MyHomePage(title: 'Flutter Demo Home Page'),
-    );
-  }
-}
-
-class MyHomePage extends StatefulWidget {
-  const MyHomePage({super.key, required this.title});
-
-  // 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
-  State<MyHomePage> 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 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>[
-            const Text(
-              'You have pushed the button this many times:',
-            ),
-            Text(
-              '$_counter',
-              style: Theme.of(context).textTheme.headline4,
-            ),
-          ],
-        ),
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: _incrementCounter,
-        tooltip: 'Increment',
-        child: const Icon(Icons.add),
-      ), // This trailing comma makes auto-formatting nicer for build methods.
-    );
-  }
-}
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:zachranobed/models/user.dart';
+import 'package:zachranobed/routes.dart';
+
+void main() {
+  runApp(const MyApp());
+}
+
+class MyApp extends StatelessWidget {
+  const MyApp({super.key});
+
+  // This widget is the root of your application.
+  @override
+  Widget build(BuildContext context) {
+    return ChangeNotifierProvider(
+      create: (context) => User(),
+      builder: (context, child) {
+        return const MaterialApp(
+          initialRoute: RouteManager.wrapper,
+          onGenerateRoute: RouteManager.generateRoute,
+        );
+      },
+    );
+  }
+}

lib/models/user.dart

@@ -0,0 +1,18 @@
+import 'package:flutter/material.dart';
+
+class User extends ChangeNotifier {
+
+  String email = "";
+  String password = "";
+
+  /*User(this.email, this.password) {
+    notifyListeners();
+  }*/
+
+  void newUser(String email, String password) {
+    this.email = email;
+    this.password = password;
+    notifyListeners();
+  }
+
+}

lib/routes.dart

@@ -0,0 +1,32 @@
+import 'package:flutter/material.dart';
+import 'package:zachranobed/ui/screens/home.dart';
+import 'package:zachranobed/ui/screens/login.dart';
+import 'package:zachranobed/ui/screens/wrapper.dart';
+
+class RouteManager {
+  static const String wrapper = '/';
+  static const String login = '/login';
+  static const String home = '/home';
+
+  static Route<dynamic> generateRoute(RouteSettings settings) {
+    switch (settings.name) {
+      case wrapper:
+        return MaterialPageRoute(
+          builder: (context) => const Wrapper(),
+        );
+
+      case login:
+        return MaterialPageRoute(
+          builder: (context) => const Login(),
+        );
+
+      case home:
+        return MaterialPageRoute(
+          builder: (context) => const Home(),
+        );
+
+      default:
+        throw const FormatException('Route not found!');
+    }
+  }
+}

lib/ui/screens/home.dart

@@ -0,0 +1,33 @@
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:zachranobed/models/user.dart';
+import 'package:zachranobed/routes.dart';
+
+class Home extends StatelessWidget {
+  const Home({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Home'),
+        actions: [
+          IconButton(
+            onPressed: () {
+              Provider.of<User>(context, listen: false).newUser('', '');
+              Navigator.of(context).pushReplacementNamed(RouteManager.login);
+            },
+            icon: Icon(Icons.exit_to_app),
+          ),
+        ],
+      ),
+      body: Center(
+        child: Consumer<User>(
+          builder: (context, user, child) {
+            return Text('Ahoj ${user.email}');
+          },
+        ),
+      ),
+    );
+  }
+}