refactor: split app wrapper from focused example code (multi-file apps)

Convert 17 multi-file apps to the validated pattern: lib/main.dart keeps
only the MaterialApp bootstrap; a new lib/example.dart holds the full entry
screen and focused example code, importing existing supporting files
(screens/, tabs/, services/, models/, widgets/, utils/).

Apps: analytics_integration, animation_example, biometrics, bottom_sheet,
custom_home_drawer, google_signin, grid_layout, handling_routes,
image_editor, scan_qr_code, statless_counter_app, using_bottom_nav_bar,
using_custom_fonts, using_listview, using_listwheelscrollview,
using_platform_adaptive, view_pdf_file

analytics_integration/lib/example.dart

@@ -0,0 +1,106 @@
+// Example: Analytics tracking with Firebase Analytics showing a list of items
+import 'package:analytics_integration/single_item_tile.dart';
+import 'package:firebase_analytics/firebase_analytics.dart';
+import 'package:flutter/material.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  /// create instance of FirebaseAnalytics as [analytics]
+  static FirebaseAnalytics analytics = FirebaseAnalytics.instance;
+
+  /// create observer for FirebaseAnalytics as [observer]
+  /// this observer sends events to Firebase Analytics when the
+  /// currently active route changes.
+  static FirebaseAnalyticsObserver observer =
+      FirebaseAnalyticsObserver(analytics: analytics);
+
+  @override
+  _ExampleState createState() => _ExampleState();
+}
+
+class _ExampleState extends State<Example> {
+  late FirebaseAnalytics _analytics;
+
+  @override
+  void initState() {
+    /// initializing data to local variable [_analytics] for Firebase Analytics
+    /// that we made before for local use
+    _analytics = Example.analytics;
+    //// below three events are related to user which we are
+    //// sending to Firebase Analytics
+    _setUserIdInAnalytics();
+    _setUserPropertyInAnalytics();
+    _currentScreen();
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: Colors.white,
+      appBar: AppBar(
+        title: Center(
+          child: Text('Flutter Analytics'),
+        ),
+      ),
+      body: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: ListView(
+          shrinkWrap: true,
+          children: <Widget>[
+            SizedBox(
+              height: 16,
+            ),
+            SingleItemTile(
+              itemName: 'Carrot',
+              analytics: _analytics,
+              quantity: 1,
+              price: '100Rs',
+            ),
+            SizedBox(
+              height: 16,
+            ),
+            SingleItemTile(
+              itemName: 'Baby Carrot',
+              analytics: _analytics,
+              quantity: .5,
+              price: '50Rs',
+            ),
+            SizedBox(
+              height: 16,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  //// to create a unique user identifier for Analytics
+  //// send user id(if you app has)
+  Future<void> _setUserIdInAnalytics() async {
+    await _analytics.setUserId(id: 'alksj39hnfn49skvnghqwp40sm');
+  }
+
+  //// sending user related field to Analytics
+  /// below [name] is the name of the user property to set
+  /// [value] is the values of that property
+  Future<void> _setUserPropertyInAnalytics() async {
+    await _analytics.setUserProperty(
+      name: 'email',
+      value: 'johndoe@gmail.com',
+    );
+  }
+
+  /// Setting the current Screen of the app in [screenName]
+  /// and sending back to Analytics
+  Future<void> _currentScreen() async {
+    await _analytics.logEvent(
+      name: 'screen_view',
+      parameters: <String, Object>{
+        'screen_name': 'FlutterAnalyticsHome',
+        'screen_class': 'FlutterAnalyticsHome',
+      },
+    );
+  }
+}

analytics_integration/lib/main.dart

@@ -1,5 +1,4 @@
-import 'package:analytics_integration/single_item_tile.dart';
+import 'package:analytics_integration/example.dart';
-import 'package:firebase_analytics/firebase_analytics.dart';
 import 'package:firebase_core/firebase_core.dart';
 import 'package:flutter/material.dart';
 
@@ -8,19 +7,10 @@ void main() async {
 
   /// initialize your firebase project
   await Firebase.initializeApp();
-  runApp(FlutterAnalyticsApp());
+  runApp(const FlutterAnalyticsApp());
 }
 
 class FlutterAnalyticsApp extends StatelessWidget {
-  /// create instance of FirebaseAnalytics as [analytics]
-  static FirebaseAnalytics analytics = FirebaseAnalytics.instance;
-
-  /// create observer for FirebaseAnalytics as [observer]
-  /// this observer sends events to Firebase Analytics when the
-  /// currently active route changes.
-  static FirebaseAnalyticsObserver observer =
-      FirebaseAnalyticsObserver(analytics: analytics);
-
   const FlutterAnalyticsApp({super.key});
 
   @override
@@ -35,114 +25,8 @@ class FlutterAnalyticsApp extends StatelessWidget {
 
       /// this is used to observe navigation changes in the app
       /// and sending data back to Firebase Analytics
-      navigatorObservers: <NavigatorObserver>[observer],
+      navigatorObservers: <NavigatorObserver>[Example.observer],
-      home: FlutterAnalyticsHome(
+      home: const Example(),
-        title: 'Flutter Analytics',
-        analytics: analytics,
-        observer: observer,
-      ),
-    );
-  }
-}
-
-class FlutterAnalyticsHome extends StatefulWidget {
-  final String title;
-  final FirebaseAnalytics analytics;
-  final FirebaseAnalyticsObserver observer;
-
-  const FlutterAnalyticsHome({
-    super.key,
-    required this.title,
-    required this.analytics,
-    required this.observer,
-  });
-
-  @override
-  _FlutterAnalyticsHomeState createState() => _FlutterAnalyticsHomeState();
-}
-
-class _FlutterAnalyticsHomeState extends State<FlutterAnalyticsHome> {
-  late FirebaseAnalytics _analytics;
-
-  @override
-  void initState() {
-    /// initializing data to local variable [_analytics] for Firebase Analytics
-    /// that we made before for local use
-    _analytics = widget.analytics;
-    //// below three events are related to user which we are
-    //// sending to Firebase Analytics
-    _setUserIdInAnalytics();
-    _setUserPropertyInAnalytics();
-    _currentScreen();
-    super.initState();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      backgroundColor: Colors.white,
-      appBar: AppBar(
-        title: Center(
-          child: Text(widget.title),
-        ),
-      ),
-      body: Padding(
-        padding: const EdgeInsets.all(16.0),
-        child: ListView(
-          shrinkWrap: true,
-          children: <Widget>[
-            SizedBox(
-              height: 16,
-            ),
-            SingleItemTile(
-              itemName: 'Carrot',
-              analytics: _analytics,
-              quantity: 1,
-              price: '100Rs',
-            ),
-            SizedBox(
-              height: 16,
-            ),
-            SingleItemTile(
-              itemName: 'Baby Carrot',
-              analytics: _analytics,
-              quantity: .5,
-              price: '50Rs',
-            ),
-            SizedBox(
-              height: 16,
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-
-  //// to create a unique user identifier for Analytics
-  //// send user id(if you app has)
-  Future<void> _setUserIdInAnalytics() async {
-    await _analytics.setUserId(id: 'alksj39hnfn49skvnghqwp40sm');
-  }
-
-  //// sending user related field to Analytics
-  /// below [name] is the name of the user property to set
-  /// [value] is the values of that property
-  Future<void> _setUserPropertyInAnalytics() async {
-    await _analytics.setUserProperty(
-      name: 'email',
-      value: 'johndoe@gmail.com',
-    );
-  }
-
-  /// Setting the current Screen of the app in [screenName]
-  /// and sending back to Analytics
-  Future<void> _currentScreen() async {
-    await _analytics.logEvent(
-      name: 'screen_view',
-      parameters: <String, Object>{
-        'screen_name': 'FlutterAnalyticsHome',
-        'screen_class': 'FlutterAnalyticsHome',
-      },
     );
   }
 }

animation_example/lib/example.dart

@@ -1,14 +1,15 @@
+// Example: A compass-like animation demo where tapping rotates a pen image
+// and points it toward a direction (north/west/south/east).
 import 'package:flutter/material.dart';
 
-class HomePage extends StatefulWidget {
+class Example extends StatefulWidget {
-  const HomePage({super.key});
+  const Example({super.key});
 
   @override
-  _HomePageState createState() => _HomePageState();
+  _ExampleState createState() => _ExampleState();
 }
 
-class _HomePageState extends State<HomePage>
+class _ExampleState extends State<Example> with SingleTickerProviderStateMixin {
-    with SingleTickerProviderStateMixin {
   late AnimationController controller;
   var target = 0.0;
   final Map<double, String> data = {
@@ -54,8 +55,7 @@ class _HomePageState extends State<HomePage>
                 child: TextButton(
                     onPressed: () {},
                     style: ButtonStyle(
-                        backgroundColor:
+                        backgroundColor: WidgetStateProperty.all(Colors.green)),
-                            WidgetStateProperty.all(Colors.green)),
                     child: const Text(
                       "North",
                       style: TextStyle(
@@ -104,8 +104,7 @@ class _HomePageState extends State<HomePage>
                 child: TextButton(
                     onPressed: () {},
                     style: ButtonStyle(
-                        backgroundColor:
+                        backgroundColor: WidgetStateProperty.all(Colors.green)),
-                            WidgetStateProperty.all(Colors.green)),
                     child: const Text(
                       "North",
                       style: TextStyle(

animation_example/lib/main.dart

@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 
-import 'home_page.dart';
+import 'example.dart';
 
 void main() {
   runApp(const MyApp());
@@ -15,10 +15,9 @@ class MyApp extends StatelessWidget {
     return MaterialApp(
       title: 'Pen Assignement',
       theme: ThemeData(
-
         primarySwatch: Colors.blue,
       ),
-      home:HomePage(),
+      home: const Example(),
     );
   }
 }

biometrics/lib/example.dart

@@ -0,0 +1,88 @@
+// Example: Biometric verification screen
+import 'package:biometrics/biometrics_verifier.dart';
+import 'package:flutter/material.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  @override
+  State<Example> createState() => _ExampleState();
+}
+
+class _ExampleState extends State<Example> {
+  late bool isVerified;
+
+  late BiometricsVerifier verifier;
+
+  @override
+  void initState() {
+    super.initState();
+    isVerified = false;
+    verifier = BiometricsVerifier();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(),
+      body: SizedBox(
+        width: double.infinity,
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Text(
+              isVerified ? 'Verification Complete' : 'Unverified',
+              style: const TextStyle(
+                fontSize: 16,
+                fontWeight: FontWeight.bold,
+              ),
+            ),
+            const SizedBox(height: 10),
+            isVerified
+                ? TextButton(
+                    onPressed: () {
+                      setState(() {
+                        isVerified = false;
+                      });
+                    },
+                    child: const Text('Unverify'),
+                  )
+                : TextButton(
+                    onPressed: () async {
+                      try {
+                        await verifier
+                            .verifyBiometrics('Please enter your fingerprint');
+                        // ---- Add your logic after finger print verification here
+                        // ---
+                        // ---
+                        setState(() {
+                          isVerified = true;
+                        });
+                      } catch (e) {
+                        // ---- Verification Failed
+                        if (!context.mounted) return;
+                        showDialog(
+                          context: context,
+                          builder: (c) => AlertDialog(
+                            title: const Text('Error !'),
+                            content: Text(e.toString()),
+                            actions: [
+                              TextButton(
+                                onPressed: () {
+                                  Navigator.of(context).pop();
+                                },
+                                child: const Text('Ok'),
+                              )
+                            ],
+                          ),
+                        );
+                      }
+                    },
+                    child: const Text('Verify with Fingerprint'),
+                  ),
+          ],
+        ),
+      ),
+    );
+  }
+}

biometrics/lib/main.dart

@@ -1,7 +1,7 @@
-import 'package:biometrics/biometrics_verifier.dart';
+import 'package:biometrics/example.dart';
 import 'package:flutter/material.dart';
 
-void main() => runApp(Biometrics());
+void main() => runApp(const Biometrics());
 
 class Biometrics extends StatelessWidget {
   const Biometrics({super.key});
@@ -13,92 +13,7 @@ class Biometrics extends StatelessWidget {
       theme: ThemeData(
         appBarTheme: const AppBarTheme(elevation: 0),
       ),
-      home: Home(),
+      home: const Example(),
-    );
-  }
-}
-
-class Home extends StatefulWidget {
-  const Home({super.key});
-
-  @override
-  State<Home> createState() => _HomeState();
-}
-
-class _HomeState extends State<Home> {
-  late bool isVerified;
-
-  late BiometricsVerifier verifier;
-
-  @override
-  void initState() {
-    super.initState();
-    isVerified = false;
-    verifier = BiometricsVerifier();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      appBar: AppBar(),
-      body: SizedBox(
-        width: double.infinity,
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: [
-            Text(
-              isVerified ? 'Verification Complete' : 'Unverified',
-              style: const TextStyle(
-                fontSize: 16,
-                fontWeight: FontWeight.bold,
-              ),
-            ),
-            const SizedBox(height: 10),
-            isVerified
-                ? TextButton(
-                    onPressed: () {
-                      setState(() {
-                        isVerified = false;
-                      });
-                    },
-                    child: const Text('Unverify'),
-                  )
-                : TextButton(
-                    onPressed: () async {
-                      try {
-                        await verifier
-                            .verifyBiometrics('Please enter your fingerprint');
-                        // ---- Add your logic after finger print verification here
-                        // ---
-                        // ---
-                        setState(() {
-                          isVerified = true;
-                        });
-                      } catch (e) {
-                        // ---- Verification Failed
-                        if (!context.mounted) return;
-                        showDialog(
-                          context: context,
-                          builder: (c) => AlertDialog(
-                            title: const Text('Error !'),
-                            content: Text(e.toString()),
-                            actions: [
-                              TextButton(
-                                onPressed: () {
-                                  Navigator.of(context).pop();
-                                },
-                                child: const Text('Ok'),
-                              )
-                            ],
-                          ),
-                        );
-                      }
-                    },
-                    child: const Text('Verify with Fingerprint'),
-                  ),
-          ],
-        ),
-      ),
     );
   }
 }

bottom_sheet/lib/example.dart

@@ -0,0 +1,12 @@
+// Example: Bottom sheet
+import 'package:bottom_sheet/home.dart';
+import 'package:flutter/material.dart';
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const MyHomePage(title: 'Bottom Sheet');
+  }
+}

bottom_sheet/lib/main.dart

@@ -1,8 +1,8 @@
+import 'package:bottom_sheet/example.dart';
 import 'package:flutter/material.dart';
-import 'package:bottom_sheet/home.dart';
 
 void main() {
-  runApp(MyApp());
+  runApp(const MyApp());
 }
 
 class MyApp extends StatelessWidget {
@@ -17,8 +17,7 @@ class MyApp extends StatelessWidget {
         primarySwatch: Colors.red,
         visualDensity: VisualDensity.adaptivePlatformDensity,
       ),
-      home: MyHomePage(title: 'Bottom Sheet'),
+      home: const Example(),
     );
   }
 }
-

custom_home_drawer/lib/example.dart

@@ -0,0 +1,12 @@
+// Example: Custom home drawer
+import 'package:custom_home_drawer/screen/home_screen.dart';
+import 'package:flutter/material.dart';
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const HomeScreen();
+  }
+}

custom_home_drawer/lib/main.dart

@@ -1,4 +1,4 @@
-import 'package:custom_home_drawer/screen/home_screen.dart';
+import 'package:custom_home_drawer/example.dart';
 import 'package:flutter/material.dart';
 
 void main() {
@@ -15,7 +15,7 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.blue,
       ),
-      home: const HomeScreen(),
+      home: const Example(),
     );
   }
 }

google_signin/lib/example.dart

@@ -0,0 +1,76 @@
+// Example: Sign in to Google and display the signed-in user's profile.
+import 'dart:async';
+
+import 'package:firebase_auth/firebase_auth.dart';
+import 'package:flutter/material.dart';
+import 'package:google_sign_in/google_sign_in.dart';
+
+import 'home.dart';
+import 'user.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  @override
+  ExampleState createState() => ExampleState();
+}
+
+class ExampleState extends State<Example> {
+  final GoogleSignIn googleSignIn = GoogleSignIn.instance;
+  late Widget userPage;
+
+  @override
+  void initState() {
+    super.initState();
+    userPage = Home(
+      onSignin: _signin,
+      onLogout: _logout,
+      showLoading: false,
+    );
+  }
+
+  Future<User?> _signin() async {
+    setState(() {
+      userPage = Home(onSignin: null, onLogout: _logout, showLoading: true);
+    });
+    try {
+      await googleSignIn.initialize();
+      final GoogleSignInAccount account = await googleSignIn.authenticate();
+      final GoogleSignInAuthentication auth = account.authentication;
+      final AuthCredential credential = GoogleAuthProvider.credential(
+        idToken: auth.idToken,
+      );
+      final UserCredential authRes =
+          await FirebaseAuth.instance.signInWithCredential(credential);
+      final User? user = authRes.user;
+      if (user == null) return null;
+
+      setState(() {
+        userPage = UserProfile(onLogout: _logout, user: user);
+      });
+
+      return user;
+    } catch (e) {
+      print(e.toString());
+      return null;
+    }
+  }
+
+  Future<void> _logout() async {
+    await googleSignIn.signOut();
+    setState(() {
+      userPage = Home(
+        onSignin: _signin,
+        onLogout: _logout,
+        showLoading: false,
+      );
+    });
+
+    print("Logged Out");
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return userPage;
+  }
+}

google_signin/lib/main.dart

@@ -1,81 +1,18 @@
-import 'dart:async';
-
-import 'package:firebase_auth/firebase_auth.dart';
 import 'package:flutter/material.dart';
-import 'package:google_sign_in/google_sign_in.dart';
 
-import 'home.dart';
+import 'example.dart';
-import 'user.dart';
 
 void main() {
-  runApp(const App());
+  runApp(const MyApp());
 }
 
-class App extends StatefulWidget {
+class MyApp extends StatelessWidget {
-  const App({super.key});
+  const MyApp({super.key});
-
-  @override
-  AppState createState() => AppState();
-}
-
-class AppState extends State<App> {
-  final GoogleSignIn googleSignIn = GoogleSignIn.instance;
-  late Widget userPage;
-
-  @override
-  void initState() {
-    super.initState();
-    userPage = Home(
-      onSignin: _signin,
-      onLogout: _logout,
-      showLoading: false,
-    );
-  }
-
-  Future<User?> _signin() async {
-    setState(() {
-      userPage = Home(onSignin: null, onLogout: _logout, showLoading: true);
-    });
-    try {
-      await googleSignIn.initialize();
-      final GoogleSignInAccount account = await googleSignIn.authenticate();
-      final GoogleSignInAuthentication auth = account.authentication;
-      final AuthCredential credential = GoogleAuthProvider.credential(
-        idToken: auth.idToken,
-      );
-      final UserCredential authRes =
-          await FirebaseAuth.instance.signInWithCredential(credential);
-      final User? user = authRes.user;
-      if (user == null) return null;
-
-      setState(() {
-        userPage = UserProfile(onLogout: _logout, user: user);
-      });
-
-      return user;
-    } catch (e) {
-      print(e.toString());
-      return null;
-    }
-  }
-
-  Future<void> _logout() async {
-    await googleSignIn.signOut();
-    setState(() {
-      userPage = Home(
-        onSignin: _signin,
-        onLogout: _logout,
-        showLoading: false,
-      );
-    });
-
-    print("Logged Out");
-  }
 
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-      home: userPage,
+      home: const Example(),
     );
   }
 }

grid_layout/lib/example.dart

@@ -0,0 +1,22 @@
+// Example: A grid layout displaying social network icons in a 2-column grid.
+import 'package:flutter/material.dart';
+
+import 'gridview.dart';
+
+class Example extends StatelessWidget {
+  Example({super.key});
+
+  final MyGridView myGridView = MyGridView();
+
+  @override
+  Widget build(BuildContext context) {
+    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("GridView Example"),
+      ),
+      body: myGridView.build(),
+    );
+  }
+}

grid_layout/lib/main.dart

@@ -1,25 +1,17 @@
 import 'package:flutter/material.dart';
-import 'package:grid_layout/gridview.dart';
+
+import 'example.dart';
 
 void main() => runApp(MyApp());
 
 class MyApp extends StatelessWidget {
-  final MyGridView myGridView = MyGridView();
+  const MyApp({super.key});
-
-  MyApp({super.key});
 
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
       debugShowCheckedModeBanner: false,
-      home: Scaffold(
+      home: Example(),
-        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("GridView Example"),
-        ),
-        body: myGridView.build(),
-      ),
     );
   }
 }

handling_routes/lib/example.dart

@@ -1,7 +1,8 @@
+// Example: A home screen with navigation to an About page via named routes.
 import 'package:flutter/material.dart';
 
-class HomePage extends StatelessWidget {
+class Example extends StatelessWidget {
-  const HomePage({super.key});
+  const Example({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -26,7 +27,9 @@ class HomePage extends StatelessWidget {
               Text(
                 "Home Page\nClick on below icon to goto About Page",
                 // Setting the style for the Text
-                style: TextStyle(fontSize: 20.0,),
+                style: TextStyle(
+                  fontSize: 20.0,
+                ),
                 // Set text alignment to center
                 textAlign: TextAlign.center,
               ),

handling_routes/lib/main.dart

@@ -1,10 +1,11 @@
 import 'package:flutter/material.dart';
 import 'package:handling_routes/screens/about.dart';
-import 'package:handling_routes/screens/home.dart';
+
+import 'example.dart';
 
 void main() {
   runApp(MaterialApp(
-    home: HomePage(), // home has implicit route set at '/'
+    home: const Example(), // home has implicit route set at '/'
     // Setup routes
     routes: <String, WidgetBuilder>{
       // Set named routes

image_editor/lib/example.dart

@@ -0,0 +1,129 @@
+// Example: Image editor screen
+import 'package:flutter/material.dart';
+import 'package:image_editor/ApplyFilters.dart';
+import 'package:image_editor/EditImg.dart';
+import 'package:image_editor/GetImg.dart';
+import 'package:image_editor/SaveInGallery.dart';
+import 'dart:io';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  @override
+  _ExampleState createState() => _ExampleState();
+}
+
+class _ExampleState extends State<Example> {
+  bool _selected = false; //to check if a image is selected or not
+  late File
+      _image; //here we will store the selected image and apply modifications
+  final double _ImageContainerHeight = 450;
+  final double _ImageContainerWidth = 400;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        backgroundColor: Colors.greenAccent[400],
+        title: Text('Flutter Image Editor'),
+      ),
+      body: Container(
+          child: Column(
+        children: <Widget>[
+          SizedBox(
+              height: _ImageContainerHeight,
+              width: _ImageContainerWidth,
+              child: _selected // checks if a image is selected or not
+                  ? Image.file(_image)
+                  : Image.asset('images/cam.png')),
+          Row(
+            children: <Widget>[
+              Spacer(
+                flex: 2,
+              ),
+              ElevatedButton(
+                  style: ElevatedButton.styleFrom(
+                      backgroundColor: Colors.greenAccent[400]),
+                  child: Text(
+                    'Get_Image', // to select a image from gallery
+                    style: TextStyle(color: Colors.white),
+                  ),
+                  onPressed: () async {
+                    var Ifile = await GetiImg(
+                        _image); // function called from GetImg.dart
+                    if (Ifile != null) {
+                      setState(() {
+                        _image = Ifile;
+                        _selected = true;
+                      });
+                    }
+                  }),
+              Spacer(
+                flex: 1,
+              ),
+              ElevatedButton(
+                  style: ElevatedButton.styleFrom(
+                      backgroundColor: Colors.greenAccent[400]),
+                  child: Text(
+                    'Edit Image', //to start editing the shape, size, etc of the selected image
+                    style: TextStyle(color: Colors.white),
+                  ),
+                  onPressed: () async {
+                    var Ifile0 = await EditImg(
+                        _image); // function called from EditImg.dart
+                    if (Ifile0 != null) {
+                      setState(() {
+                        _image = Ifile0;
+                      });
+                    }
+                  }),
+              Spacer(
+                flex: 2,
+              ),
+            ],
+          ),
+          Row(
+            children: <Widget>[
+              Spacer(
+                flex: 2,
+              ),
+              ElevatedButton(
+                  style: ElevatedButton.styleFrom(
+                      backgroundColor: Colors.greenAccent[400]),
+                  child: Text(
+                    'Apply Filters', //to start apply various photo filters to the selected image
+                    style: TextStyle(color: Colors.white),
+                  ),
+                  onPressed: () async {
+                    var Ifile0 = await ApplyFilters(context,
+                        _image); // function called from ApplyFilters.dart
+                    if (Ifile0 != null) {
+                      setState(() {
+                        _image = Ifile0;
+                      });
+                    }
+                  }),
+              Spacer(
+                flex: 1,
+              ),
+              ElevatedButton(
+                  style: ElevatedButton.styleFrom(
+                      backgroundColor: Colors.greenAccent[400]),
+                  child: Text(
+                    'Download Editted image', //to save the edited  image to gallery
+                    style: TextStyle(color: Colors.white),
+                  ),
+                  onPressed: () async {
+                    await SaveImg(
+                        _image); // function called from SaveInGallery.dart
+                  }),
+              Spacer(
+                flex: 2,
+              ),
+            ],
+          ),
+        ],
+      )),
+    );
+  }
+}

image_editor/lib/main.dart

@@ -1,8 +1,8 @@
 import 'package:flutter/material.dart';
-import 'package:image_editor/HomePage.dart';
+import 'package:image_editor/example.dart';
 
 void main() {
-  runApp(MyApp());
+  runApp(const MyApp());
 }
 
 class MyApp extends StatelessWidget {
@@ -11,10 +11,8 @@ class MyApp extends StatelessWidget {
   // This widget is the root of your application.
   @override
   Widget build(BuildContext context) {
-    return MaterialApp(
+    return const MaterialApp(
-      home: HomePage()
+      home: Example(),
     );
   }
 }
-
-

scan_qr_code/lib/example.dart

@@ -0,0 +1,80 @@
+// Example: Scan QR code
+import 'package:flutter/material.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
+import 'package:scan_qr_code/utils/qr_code_scanner.dart';
+import 'package:scan_qr_code/utils/scanner_box_border_painter.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key, this.title = 'Code Scanner Demo'});
+
+  final String title;
+
+  @override
+  State<Example> createState() => _ExampleState();
+}
+
+class _ExampleState extends State<Example> {
+  final MobileScannerController _mobileScannerController =
+      MobileScannerController();
+  late void Function(BarcodeCapture) _onDetect;
+  bool _isScanning = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _onDetect = (BarcodeCapture capture) {
+      _mobileScannerController.stop();
+      showDialog(
+          context: context,
+          builder: (BuildContext context) {
+            return AlertDialog(
+              title: const Text('Code info'),
+              content: Text(
+                  capture.barcodes.first.rawValue?.trim() ?? 'No data found',
+                  textAlign: TextAlign.center),
+              actions: [
+                TextButton(
+                    onPressed: () => Navigator.pop(context),
+                    child: const Text('OK'))
+              ],
+            );
+          }).then((value) {
+        _mobileScannerController.start();
+        setState(() {
+          _isScanning = true;
+        });
+      });
+
+      setState(() {
+        _isScanning = false;
+      });
+    };
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: Text(widget.title)),
+      body: Center(
+        child: SizedBox.square(
+          dimension: MediaQuery.of(context).size.width - 48.0,
+          child: Padding(
+            padding: const EdgeInsets.all(
+                2.5), // Required otherwise side edges hides under outside padding
+            child: CustomPaint(
+              foregroundPainter: ScannerBoxBorderPainter(
+                  borderColor: _isScanning ? Colors.black : Colors.green),
+              child: Padding(
+                padding: const EdgeInsets.all(
+                    2.5), // Required otherwise scanner hides under side edges
+                child: QRCodeScanner(
+                    mobileScannerController: _mobileScannerController,
+                    onDetect: _onDetect),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

scan_qr_code/lib/main.dart

@@ -1,8 +1,5 @@
-
 import 'package:flutter/material.dart';
-import 'package:mobile_scanner/mobile_scanner.dart';
+import 'package:scan_qr_code/example.dart';
-import 'package:scan_qr_code/utils/qr_code_scanner.dart';
-import 'package:scan_qr_code/utils/scanner_box_border_painter.dart';
 
 void main() => runApp(const MyApp());
 
@@ -13,82 +10,7 @@ class MyApp extends StatelessWidget {
   Widget build(BuildContext context) {
     return const MaterialApp(
       title: 'Code Scanner',
-      home: MyHomePage(title: 'Code Scanner Demo'),
+      home: Example(),
-    );
-  }
-}
-
-class MyHomePage extends StatefulWidget {
-  const MyHomePage({super.key, required this.title});
-
-  final String title;
-
-  @override
-  State<MyHomePage> createState() => _MyHomePageState();
-}
-
-class _MyHomePageState extends State<MyHomePage> {
-  final MobileScannerController _mobileScannerController =
-      MobileScannerController();
-  late void Function(BarcodeCapture) _onDetect;
-  bool _isScanning = true;
-
-  @override
-  void initState() {
-    super.initState();
-    _onDetect = (BarcodeCapture capture) {
-      _mobileScannerController.stop();
-      showDialog(
-          context: context,
-          builder: (BuildContext context) {
-            return AlertDialog(
-              title: const Text('Code info'),
-              content: Text(
-                  capture.barcodes.first.rawValue?.trim() ?? 'No data found',
-                  textAlign: TextAlign.center),
-              actions: [
-                TextButton(
-                    onPressed: () => Navigator.pop(context),
-                    child: const Text('OK'))
-              ],
-            );
-          }).then((value) {
-        _mobileScannerController.start();
-        setState(() {
-          _isScanning = true;
-        });
-      });
-
-      setState(() {
-        _isScanning = false;
-      });
-    };
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      appBar: AppBar(title: Text(widget.title)),
-      body: Center(
-        child: SizedBox.square(
-          dimension: MediaQuery.of(context).size.width - 48.0,
-          child: Padding(
-            padding: const EdgeInsets.all(
-                2.5), // Required otherwise side edges hides under outside padding
-            child: CustomPaint(
-              foregroundPainter: ScannerBoxBorderPainter(
-                  borderColor: _isScanning ? Colors.black : Colors.green),
-              child: Padding(
-                padding: const EdgeInsets.all(
-                    2.5), // Required otherwise scanner hides under side edges
-                child: QRCodeScanner(
-                    mobileScannerController: _mobileScannerController,
-                    onDetect: _onDetect),
-              ),
-            ),
-          ),
-        ),
-      ),
     );
   }
 }

statless_counter_app/lib/example.dart

@@ -0,0 +1,42 @@
+// Example: Stateless widget counter using MobX
+import 'package:flutter/material.dart';
+import 'package:flutter_mobx/flutter_mobx.dart';
+
+import 'counter.dart'; // Import the Counter
+
+final counter = Counter(); // Instantiate the store
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('MobX Stateless Widget Counter'),
+      ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            Text(
+              'You have pushed the button this many times:',
+            ),
+            // Wrapping in the Observer will automatically re-render on changes to counter.value
+            Observer(
+              builder: (_) => Text(
+                '${counter.value}',
+                style: Theme.of(context).textTheme.headlineSmall,
+              ),
+            ),
+          ],
+        ),
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: counter.increment,
+        tooltip: 'Increment',
+        child: Icon(Icons.add),
+      ),
+    );
+  }
+}

statless_counter_app/lib/main.dart

@@ -1,11 +1,8 @@
 import 'package:flutter/material.dart';
-import 'package:flutter_mobx/flutter_mobx.dart';
 
-import 'counter.dart'; // Import the Counter
+import 'example.dart';
 
-final counter = Counter(); // Instantiate the store
+void main() => runApp(const MyApp());
-
-void main() => runApp(MyApp());
 
 class MyApp extends StatelessWidget {
   const MyApp({super.key});
@@ -19,42 +16,7 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.blue,
       ),
-      home: const MyHomePage(),
+      home: const Example(),
     );
   }
 }
-
-class MyHomePage extends StatelessWidget {
-  const MyHomePage({super.key});
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      appBar: AppBar(
-        title: Text('MobX Stateless Widget Counter'),
-      ),
-      body: Center(
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
-            Text(
-              'You have pushed the button this many times:',
-            ),
-            // Wrapping in the Observer will automatically re-render on changes to counter.value
-            Observer(
-              builder: (_) => Text(
-                '${counter.value}',
-                style: Theme.of(context).textTheme.headlineSmall,
-              ),
-            ),
-          ],
-        ),
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: counter.increment,
-        tooltip: 'Increment',
-        child: Icon(Icons.add),
-      ),
-    );
-  }
-}

using_bottom_nav_bar/lib/example.dart

@@ -0,0 +1,75 @@
+// Example: Using bottom navigation bar with tabs
+import 'package:flutter/material.dart';
+import 'package:using_bottom_nav_bar/tabs/first.dart';
+import 'package:using_bottom_nav_bar/tabs/second.dart';
+import 'package:using_bottom_nav_bar/tabs/third.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  @override
+  ExampleState createState() => ExampleState();
+}
+
+// SingleTickerProviderStateMixin is used for animation
+class ExampleState extends State<Example> with SingleTickerProviderStateMixin {
+  // Create a tab controller
+  late TabController controller;
+
+  @override
+  void initState() {
+    super.initState();
+
+    // Initialize the Tab Controller
+    controller = TabController(length: 3, vsync: this);
+  }
+
+  @override
+  void dispose() {
+    // Dispose of the Tab Controller
+    controller.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      // Appbar
+      appBar: AppBar(
+        // Title
+        title: Text("Using Bottom Navigation Bar"),
+        // Set the background color of the App Bar
+        backgroundColor: Colors.blue,
+      ),
+      // Set the TabBar view as the body of the Scaffold
+      body: TabBarView(
+        // Add tabs as widgets
+        controller: controller,
+        // Add tabs as widgets
+        children: <Widget>[FirstTab(), SecondTab(), ThirdTab()],
+      ),
+      // Set the bottom navigation bar
+      bottomNavigationBar: Material(
+        // set the color of the bottom navigation bar
+        color: Colors.blue,
+        // set the tab bar as the child of bottom navigation bar
+        child: TabBar(
+          tabs: <Tab>[
+            Tab(
+              // set icon to the tab
+              icon: Icon(Icons.favorite),
+            ),
+            Tab(
+              icon: Icon(Icons.adb),
+            ),
+            Tab(
+              icon: Icon(Icons.airport_shuttle),
+            ),
+          ],
+          // setup the controller
+          controller: controller,
+        ),
+      ),
+    );
+  }
+}

using_bottom_nav_bar/lib/main.dart

@@ -1,82 +1,20 @@
 import 'package:flutter/material.dart';
-import 'package:using_bottom_nav_bar/tabs/first.dart';
+import 'package:using_bottom_nav_bar/example.dart';
-import 'package:using_bottom_nav_bar/tabs/second.dart';
-import 'package:using_bottom_nav_bar/tabs/third.dart';
 
 void main() {
-  runApp(MaterialApp(
+  runApp(const MyApp());
-      // Title
-      title: "Using Tabs",
-      // Home
-      home: MyHome()));
 }
 
-class MyHome extends StatefulWidget {
+class MyApp extends StatelessWidget {
-  const MyHome({super.key});
+  const MyApp({super.key});
-
-  @override
-  MyHomeState createState() => MyHomeState();
-}
-
-// SingleTickerProviderStateMixin is used for animation
-class MyHomeState extends State<MyHome> with SingleTickerProviderStateMixin {
-  // Create a tab controller
-  late TabController controller;
-
-  @override
-  void initState() {
-    super.initState();
-
-    // Initialize the Tab Controller
-    controller = TabController(length: 3, vsync: this);
-  }
-
-  @override
-  void dispose() {
-    // Dispose of the Tab Controller
-    controller.dispose();
-    super.dispose();
-  }
 
   @override
   Widget build(BuildContext context) {
-    return Scaffold(
+    return MaterialApp(
-      // Appbar
+      // Title
-      appBar: AppBar(
+      title: "Using Tabs",
-        // Title
+      // Home
-        title: Text("Using Bottom Navigation Bar"),
+      home: const Example(),
-        // Set the background color of the App Bar
-        backgroundColor: Colors.blue,
-      ),
-      // Set the TabBar view as the body of the Scaffold
-      body: TabBarView(
-        // Add tabs as widgets
-        controller: controller,
-        // Add tabs as widgets
-        children: <Widget>[FirstTab(), SecondTab(), ThirdTab()],
-      ),
-      // Set the bottom navigation bar
-      bottomNavigationBar: Material(
-        // set the color of the bottom navigation bar
-        color: Colors.blue,
-        // set the tab bar as the child of bottom navigation bar
-        child: TabBar(
-          tabs: <Tab>[
-            Tab(
-              // set icon to the tab
-              icon: Icon(Icons.favorite),
-            ),
-            Tab(
-              icon: Icon(Icons.adb),
-            ),
-            Tab(
-              icon: Icon(Icons.airport_shuttle),
-            ),
-          ],
-          // setup the controller
-          controller: controller,
-        ),
-      ),
     );
   }
 }

using_custom_fonts/lib/example.dart

@@ -0,0 +1,31 @@
+// Example: Displays text using a custom font loaded from the app's assets.
+import 'package:flutter/material.dart';
+
+import './utils.dart' as utils;
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      // Appbar
+      appBar: AppBar(
+        // Title
+        title: Text("Using Custom Fonts"),
+      ),
+      // Body
+      body: Container(
+        // Center the content
+        child: Center(
+          // Add Text
+          child: Text("The quick brown fox jumps over the lazy dog",
+              // Center align text
+              textAlign: TextAlign.center,
+              // set a text style which defines a custom font
+              style: utils.getCustomFontTextStyle()),
+        ),
+      ),
+    );
+  }
+}

using_custom_fonts/lib/main.dart

@@ -1,29 +1,12 @@
 import 'package:flutter/material.dart';
 
-import './utils.dart' as utils;
+import 'example.dart';
 
 void main() {
   runApp(MaterialApp(
-      // Title
+    // Title
-      title: "Using Custom Fonts",
+    title: "Using Custom Fonts",
-      // Home
+    // Home
-      home: Scaffold(
+    home: const Example(),
-        // Appbar
+  ));
-        appBar: AppBar(
-          // Title
-          title: Text("Using Custom Fonts"),
-        ),
-        // Body
-        body: Container(
-          // Center the content
-          child: Center(
-            // Add Text
-            child: Text("The quick brown fox jumps over the lazy dog",
-                // Center align text
-                textAlign: TextAlign.center,
-                // set a text style which defines a custom font
-                style: utils.getCustomFontTextStyle()),
-          ),
-        ),
-      )));
 }

using_listview/lib/example.dart

@@ -0,0 +1,17 @@
+// Example: A scrollable list of contacts with avatar, name, and email.
+import 'package:flutter/material.dart';
+import 'package:using_listview/contact_page.dart';
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text("Using Listview"),
+      ),
+      body: const ContactPage(),
+    );
+  }
+}

using_listview/lib/main.dart

@@ -1,14 +1,10 @@
 import 'package:flutter/material.dart';
-import 'package:using_listview/contact_page.dart';
+
+import 'example.dart';
 
 void main() {
   runApp(MaterialApp(
     debugShowCheckedModeBanner: false,
-    home: Scaffold(
+    home: const Example(),
-      appBar: AppBar(
-        title: Text("Using Listview"),
-      ),
-      body: ContactPage(),
-    ),
   ));
 }

using_listwheelscrollview/lib/example.dart

@@ -0,0 +1,12 @@
+// Example: List wheel scroll view
+import 'package:flutter/material.dart';
+import 'listwheel.dart';
+
+class Example extends StatelessWidget {
+  const Example({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const Listwheel();
+  }
+}

using_listwheelscrollview/lib/main.dart

@@ -1,21 +1,21 @@
-import 'package:flutter/material.dart';
+import 'package:flutter/material.dart';
-import 'listwheel.dart';
+import 'example.dart';
-
+
-void main() {
+void main() {
-  runApp(MyApp());
+  runApp(const MyApp());
-}
+}
-
+
-class MyApp extends StatelessWidget {
+class MyApp extends StatelessWidget {
-  const MyApp({super.key});
+  const MyApp({super.key});
-
+
-  // This widget is the root of your application.
+  // This widget is the root of your application.
-  @override
+  @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context) {
-    return MaterialApp(
+    return MaterialApp(
-      theme: ThemeData.dark().copyWith(
+      theme: ThemeData.dark().copyWith(
-        scaffoldBackgroundColor: Color(0XFF0A0E21),
+        scaffoldBackgroundColor: Color(0XFF0A0E21),
-      ),
+      ),
-      home: Listwheel(),
+      home: const Example(),
-    );
+    );
-  }
+  }
-}
+}

using_platform_adaptive/lib/example.dart

@@ -0,0 +1,123 @@
+// Example: Platform adaptive widgets
+import 'package:flutter/material.dart';
+import 'package:using_platform_adaptive/common_widgets/adaptive_button.dart';
+import 'package:using_platform_adaptive/common_widgets/adaptive_date_picker.dart';
+import 'package:using_platform_adaptive/common_widgets/adaptive_indicator.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key, this.title = 'Using Platform Adaptive'});
+  final String title;
+
+  @override
+  State<Example> createState() => _ExampleState();
+}
+
+class _ExampleState extends State<Example> {
+  TargetPlatform? selectedPlatform;
+  final String introText = "Flutter's flagship feature is it's ability to write"
+      " code once and have it run on multiple devices. While this is great, sometimes"
+      " you want the user interface to look more native to its platform. This project"
+      " showcases the Platform Adaptive pattern, a powerful pattern that allows you"
+      " to create widgets that you write once and look natural on any device. The"
+      " demo is just set up to work on android and iOS but can be extended to work"
+      " on web, native and any other platform flutter supports.";
+
+  @override
+  Widget build(BuildContext context) {
+    final platforms = {
+      "Default": null,
+      "Android": TargetPlatform.android,
+      "iOS": TargetPlatform.iOS,
+    };
+    return Scaffold(
+      backgroundColor: Colors.white,
+      appBar: AppBar(
+        title: Text(widget.title),
+      ),
+      body: Container(
+        padding: const EdgeInsets.all(30),
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.start,
+          children: <Widget>[
+            Text(introText),
+            const SizedBox(height: 30),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                const Text("Force a platform:  "),
+                DropdownButton(
+                  value: selectedPlatform,
+                  items: List<DropdownMenuItem>.from(platforms.entries.map(
+                      (e) => DropdownMenuItem(
+                          value: e.value, child: Text(e.key)))),
+                  onChanged: (value) {
+                    setState(() {
+                      selectedPlatform = value;
+                    });
+                  },
+                ),
+              ],
+            ),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                const Text("Buttons:  "),
+                AdaptiveButton(
+                  forcePlatform: selectedPlatform,
+                  color: Colors.teal,
+                  onPressed: () {},
+                  child: const Text("I'm a button"),
+                ),
+              ],
+            ),
+            const SizedBox(height: 10),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                const Text("Dialogs:  "),
+                AdaptiveButton(
+                  forcePlatform: selectedPlatform,
+                  color: Colors.teal,
+                  onPressed: () {
+                    showDialog(
+                        context: context,
+                        builder: (context) {
+                          return AdaptiveDialog(
+                            title: "Test",
+                            content: const Text("This is the content area"),
+                            actions: [
+                              AdaptiveDialogAction(
+                                text: "Action 1",
+                                forcePlatform: selectedPlatform,
+                                onPressed: () {},
+                              ),
+                              AdaptiveDialogAction(
+                                text: "Action 2",
+                                forcePlatform: selectedPlatform,
+                                onPressed: () {},
+                              ),
+                            ],
+                            forcePlatform: selectedPlatform,
+                          );
+                        });
+                  },
+                  child: const Text("Show"),
+                ),
+              ],
+            ),
+            const SizedBox(height: 10),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                const Text("Loading Indicator:   "),
+                AdaptiveIndicator(
+                  forcePlatform: selectedPlatform,
+                ),
+              ],
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

using_platform_adaptive/lib/main.dart

@@ -1,7 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:using_platform_adaptive/common_widgets/adaptive_button.dart';
+import 'package:using_platform_adaptive/example.dart';
-import 'package:using_platform_adaptive/common_widgets/adaptive_date_picker.dart';
-import 'package:using_platform_adaptive/common_widgets/adaptive_indicator.dart';
 
 void main() {
   runApp(const MyApp());
@@ -18,125 +16,7 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.teal,
       ),
-      home: const MyHomePage(title: 'Using Platform Adaptive'),
+      home: const Example(),
-    );
-  }
-}
-
-class MyHomePage extends StatefulWidget {
-  const MyHomePage({super.key, required this.title});
-  final String title;
-
-  @override
-  State<MyHomePage> createState() => _MyHomePageState();
-}
-
-class _MyHomePageState extends State<MyHomePage> {
-  TargetPlatform? selectedPlatform;
-  final String introText = "Flutter's flagship feature is it's ability to write"
-      " code once and have it run on multiple devices. While this is great, sometimes"
-      " you want the user interface to look more native to its platform. This project"
-      " showcases the Platform Adaptive pattern, a powerful pattern that allows you"
-      " to create widgets that you write once and look natural on any device. The"
-      " demo is just set up to work on android and iOS but can be extended to work"
-      " on web, native and any other platform flutter supports.";
-
-  @override
-  Widget build(BuildContext context) {
-    final platforms = {
-      "Default": null,
-      "Android": TargetPlatform.android,
-      "iOS": TargetPlatform.iOS,
-    };
-    return Scaffold(
-      backgroundColor: Colors.white,
-      appBar: AppBar(
-        title: Text(widget.title),
-      ),
-      body: Container(
-        padding: const EdgeInsets.all(30),
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.start,
-          children: <Widget>[
-            Text(introText),
-            const SizedBox(height: 30),
-            Row(
-              mainAxisAlignment: MainAxisAlignment.center,
-              children: [
-                const Text("Force a platform:  "),
-                DropdownButton(
-                  value: selectedPlatform,
-                  items: List<DropdownMenuItem>.from(platforms.entries.map(
-                      (e) => DropdownMenuItem(
-                          value: e.value, child: Text(e.key)))),
-                  onChanged: (value) {
-                    setState(() {
-                      selectedPlatform = value;
-                    });
-                  },
-                ),
-              ],
-            ),
-            Row(
-              mainAxisAlignment: MainAxisAlignment.center,
-              children: [
-                const Text("Buttons:  "),
-                AdaptiveButton(
-                  forcePlatform: selectedPlatform,
-                  color: Colors.teal,
-                  onPressed: () {},
-                  child: const Text("I'm a button"),
-                ),
-              ],
-            ),
-            const SizedBox(height: 10),
-            Row(
-              mainAxisAlignment: MainAxisAlignment.center,
-              children: [
-                const Text("Dialogs:  "),
-                AdaptiveButton(
-                  forcePlatform: selectedPlatform,
-                  color: Colors.teal,
-                  onPressed: () {
-                    showDialog(
-                        context: context,
-                        builder: (context) {
-                          return AdaptiveDialog(
-                            title: "Test",
-                            content: const Text("This is the content area"),
-                            actions: [
-                              AdaptiveDialogAction(
-                                text: "Action 1",
-                                forcePlatform: selectedPlatform,
-                                onPressed: () {},
-                              ),
-                              AdaptiveDialogAction(
-                                text: "Action 2",
-                                forcePlatform: selectedPlatform,
-                                onPressed: () {},
-                              ),
-                            ],
-                            forcePlatform: selectedPlatform,
-                          );
-                        });
-                  },
-                  child: const Text("Show"),
-                ),
-              ],
-            ),
-            const SizedBox(height: 10),
-            Row(
-              mainAxisAlignment: MainAxisAlignment.center,
-              children: [
-                const Text("Loading Indicator:   "),
-                AdaptiveIndicator(
-                  forcePlatform: selectedPlatform,
-                ),
-              ],
-            ),
-          ],
-        ),
-      ),
     );
   }
 }

view_pdf_file/lib/example.dart

@@ -0,0 +1,84 @@
+// Example: View PDF file
+import 'package:flutter/material.dart';
+import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
+import 'package:view_pdf_file/constants.dart';
+import 'package:view_pdf_file/viewPDF.dart';
+
+class Example extends StatefulWidget {
+  const Example({super.key});
+
+  @override
+  ExampleState createState() => ExampleState();
+}
+
+class ExampleState extends State<Example> {
+  bool isLoading = false;
+  late Widget pdfViewer;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text("View PDF File"),
+      ),
+      body: Container(
+        child: Center(
+          child: isLoading
+              ? CircularProgressIndicator()
+              : Column(
+                  crossAxisAlignment: CrossAxisAlignment.center,
+                  mainAxisAlignment: MainAxisAlignment.center,
+                  mainAxisSize: MainAxisSize.max,
+                  children: [
+                    ElevatedButton(
+                      onPressed: () {
+                        loadFromAsset();
+                      },
+                      child: Text("Load local PDF"),
+                    ),
+                    ElevatedButton(
+                      onPressed: () {
+                        loadFromURL();
+                      },
+                      child: Text("Load PDF via URL"),
+                    ),
+                  ],
+                ),
+        ),
+      ),
+    );
+  }
+
+  Future<void> loadFromAsset() async {
+    setState(() {
+      isLoading = true;
+    });
+    pdfViewer = SfPdfViewer.asset('assets/Hello.pdf');
+    setState(() {
+      isLoading = false;
+    });
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (_) => ViewPDF(viewer: pdfViewer),
+      ),
+    );
+  }
+
+  Future<void> loadFromURL() async {
+    setState(() {
+      isLoading = true;
+    });
+
+    pdfViewer = SfPdfViewer.network(Constants.pdfURL);
+    setState(() {
+      isLoading = false;
+    });
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (_) => ViewPDF(viewer: pdfViewer),
+      ),
+    );
+  }
+}

view_pdf_file/lib/main.dart

@@ -1,10 +1,8 @@
 import 'package:flutter/material.dart';
-import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
+import 'package:view_pdf_file/example.dart';
-import 'package:view_pdf_file/constants.dart';
-import 'package:view_pdf_file/viewPDF.dart';
 
 void main() {
-  runApp(MyApp());
+  runApp(const MyApp());
 }
 
 class MyApp extends StatelessWidget {
@@ -18,85 +16,6 @@ class MyApp extends StatelessWidget {
           primarySwatch: Colors.blue,
           visualDensity: VisualDensity.adaptivePlatformDensity,
         ),
-        home: HomePage());
+        home: const Example());
-  }
-}
-
-class HomePage extends StatefulWidget {
-  const HomePage({super.key});
-
-  @override
-  _HomePageState createState() => _HomePageState();
-}
-
-class _HomePageState extends State<HomePage> {
-  bool isLoading = false;
-  late Widget pdfViewer;
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      appBar: AppBar(
-        title: Text("View PDF File"),
-      ),
-      body: Container(
-        child: Center(
-          child: isLoading
-              ? CircularProgressIndicator()
-              : Column(
-                  crossAxisAlignment: CrossAxisAlignment.center,
-                  mainAxisAlignment: MainAxisAlignment.center,
-                  mainAxisSize: MainAxisSize.max,
-                  children: [
-                    ElevatedButton(
-                      onPressed: () {
-                        loadFromAsset();
-                      },
-                      child: Text("Load local PDF"),
-                    ),
-                    ElevatedButton(
-                      onPressed: () {
-                        loadFromURL();
-                      },
-                      child: Text("Load PDF via URL"),
-                    ),
-                  ],
-                ),
-        ),
-      ),
-    );
-  }
-
-  Future<void> loadFromAsset() async {
-    setState(() {
-      isLoading = true;
-    });
-    pdfViewer = SfPdfViewer.asset('assets/Hello.pdf');
-    setState(() {
-      isLoading = false;
-    });
-    Navigator.push(
-      context,
-      MaterialPageRoute(
-        builder: (_) => ViewPDF(viewer: pdfViewer),
-      ),
-    );
-  }
-
-  Future<void> loadFromURL() async {
-    setState(() {
-      isLoading = true;
-    });
-
-    pdfViewer = SfPdfViewer.network(Constants.pdfURL);
-    setState(() {
-      isLoading = false;
-    });
-    Navigator.push(
-      context,
-      MaterialPageRoute(
-        builder: (_) => ViewPDF(viewer: pdfViewer),
-      ),
-    );
   }
 }