Initial Commit

example/lib/main.dart

@@ -0,0 +1,199 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:modal_progress_hud_nsn/modal_progress_hud_nsn.dart';
+
+void main() => runApp(MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      theme: ThemeData(
+        primarySwatch: Colors.blue,
+      ),
+      home: LoginPage(
+        onSignIn: () => print('login successful!'),
+      ),
+    );
+  }
+}
+
+class LoginPage extends StatefulWidget {
+  final VoidCallback _onSignIn;
+
+  LoginPage({@required onSignIn})
+      : assert(onSignIn != null),
+        _onSignIn = onSignIn;
+
+  @override
+  _LoginPageState createState() => _LoginPageState();
+}
+
+class _LoginPageState extends State<LoginPage> {
+  // maintains validators and state of form fields
+  final GlobalKey<FormState> _loginFormKey = GlobalKey<FormState>();
+
+  // manage state of modal progress HUD widget
+  bool _isInAsyncCall = false;
+
+  bool _isInvalidAsyncUser = false; // managed after response from server
+  bool _isInvalidAsyncPass = false; // managed after response from server
+
+  String _username;
+  String _password;
+  bool _isLoggedIn = false;
+
+  // validate user name
+  String _validateUserName(String userName) {
+    if (userName.length < 8) {
+      return 'Username must be at least 8 characters';
+    }
+
+    if (_isInvalidAsyncUser) {
+      // disable message until after next async call
+      _isInvalidAsyncUser = false;
+      return 'Incorrect user name';
+    }
+
+    return null;
+  }
+
+  // validate password
+  String _validatePassword(String password) {
+    if (password.length < 8) {
+      return 'Password must be at least 8 characters';
+    }
+
+    if (_isInvalidAsyncPass) {
+      // disable message until after next async call
+      _isInvalidAsyncPass = false;
+      return 'Incorrect password';
+    }
+
+    return null;
+  }
+
+  void _submit() {
+    if (_loginFormKey.currentState.validate()) {
+      _loginFormKey.currentState.save();
+
+      // dismiss keyboard during async call
+      FocusScope.of(context).requestFocus(new FocusNode());
+
+      // start the modal progress HUD
+      setState(() {
+        _isInAsyncCall = true;
+      });
+
+      // Simulate a service call
+      Future.delayed(Duration(seconds: 1), () {
+        final _accountUsername = 'username1';
+        final _accountPassword = 'password1';
+        setState(() {
+          if (_username == _accountUsername) {
+            _isInvalidAsyncUser = false;
+            if (_password == _accountPassword) {
+              // username and password are correct
+              _isInvalidAsyncPass = false;
+              _isLoggedIn = true;
+            } else
+              // username is correct, but password is incorrect
+              _isInvalidAsyncPass = true;
+          } else {
+            // incorrect username and have not checked password result
+            _isInvalidAsyncUser = true;
+            // no such user, so no need to trigger async password validator
+            _isInvalidAsyncPass = false;
+          }
+          // stop the modal progress HUD
+          _isInAsyncCall = false;
+        });
+        if (_isLoggedIn)
+          // do something
+          widget._onSignIn();
+      });
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Modal Progress HUD Demo'),
+        backgroundColor: Colors.blue,
+      ),
+      // display modal progress HUD (heads-up display, or indicator)
+      // when in async call
+      body: ModalProgressHUD(
+        child: SingleChildScrollView(
+          child: Container(
+            padding: const EdgeInsets.all(16.0),
+            child: buildLoginForm(context),
+          ),
+        ),
+        inAsyncCall: _isInAsyncCall,
+        // demo of some additional parameters
+        opacity: 0.5,
+        progressIndicator: CircularProgressIndicator(),
+      ),
+    );
+  }
+
+  Widget buildLoginForm(BuildContext context) {
+    final TextTheme textTheme = Theme.of(context).textTheme;
+    // run the validators on reload to process async results
+    _loginFormKey.currentState?.validate();
+    return Form(
+      key: this._loginFormKey,
+      child: Column(
+        children: [
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: TextFormField(
+              key: Key('username'),
+              decoration: InputDecoration(
+                  hintText: 'enter username', labelText: 'User Name'),
+              style: TextStyle(fontSize: 20.0, color: textTheme.button.color),
+              validator: _validateUserName,
+              onSaved: (value) => _username = value,
+            ),
+          ),
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: TextFormField(
+              key: Key('password'),
+              obscureText: true,
+              decoration: InputDecoration(
+                  hintText: 'enter password', labelText: 'Password'),
+              style: TextStyle(fontSize: 20.0, color: textTheme.button.color),
+              validator: _validatePassword,
+              onSaved: (value) => _password = value,
+            ),
+          ),
+          Padding(
+            padding: const EdgeInsets.all(32.0),
+            child: ElevatedButton(
+              onPressed: _submit,
+              child: Text('Login'),
+            ),
+          ),
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: _isLoggedIn
+                ? Text(
+                    'Login successful!',
+                    key: Key('loggedIn'),
+                    style: TextStyle(fontSize: 20.0),
+                  )
+                : Text(
+                    'Not logged in',
+                    key: Key('notLoggedIn'),
+                    style: TextStyle(fontSize: 20.0),
+                  ),
+          ),
+        ],
+      ),
+    );
+  }
+}