Data passing from One page to Another

 import "package:flutter/material.dart";

/// EXAMPLE 1 : Using StatelessWidget as shown below
// void main()
// {
//   runApp(MyApp());
// }
// class MyApp extends StatelessWidget
// {
//   MyApp({super.key});
//
//   @override
//   Widget build(BuildContext context)
//   {
//     return MaterialApp(
//       title: "Data Passing through TextField",
//       debugShowCheckedModeBanner: false,
//       theme: ThemeData(
//         primarySwatch: Colors.brown,
//       ),
//       home: FirstDemo(),
//     );
//   }
// }
//
// class FirstDemo extends StatefulWidget
// {
//   @override
//   State<FirstDemo> createState()
//   {
//     return FirstDemoState();
//   }
// }
//
// class FirstDemoState extends State<FirstDemo>
// {
//   TextEditingController txt1 = new TextEditingController();
//   TextEditingController txt2 = new TextEditingController();
//   TextEditingController txt3 = new TextEditingController();
//
//   @override
//   Widget build(BuildContext context)
//   {
//     return Scaffold(
//       appBar: AppBar(
//         title: const Text("This is First Page"),
//         centerTitle: true,
//       ),
//       body: Center(
//         child: Container(
//           width: 330.0,
//           child: Column(
//             mainAxisAlignment: MainAxisAlignment.center,
//             children: [
//               TextField(
//                 controller: txt1,
//                 decoration: InputDecoration(
//                   hintText: "Enter the Email",
//                   labelText: "Email",
//                   border: OutlineInputBorder(),
//                 ),
//               ),
//               const SizedBox(height: 20.0),
//               TextField(
//                 controller: txt2,
//                 decoration: InputDecoration(
//                   hintText: "Enter the Username",
//                   labelText: "Username",
//                   border: OutlineInputBorder(),
//                 ),
//               ),
//               const SizedBox(height: 20.0),
//               TextField(
//                 controller: txt3,
//                 decoration: InputDecoration(
//                   hintText: "Enter the Password",
//                   labelText: "Password",
//                   border: OutlineInputBorder(),
//                 ),
//               ),
//               const SizedBox(height: 30.0),
//               ElevatedButton(
//                 onPressed: (){
//                   Navigator.push(
//                     context,
//                     MaterialPageRoute(
//                       builder: (context){
//                         return SecondDemo(
//                           username: txt1.text,
//                           email: txt2.text,
//                           password: txt3.text,
//                         );
//                       },
//                     ),
//                   );
//                 },
//                 child: const Text("Go to Next Page"),
//               ),
//             ],
//           ),
//         ),
//       ),
//     );
//   }
// }
//
// class SecondDemo extends StatelessWidget
// {
//   final String username, email, password;
//   SecondDemo({super.key, required this.username, required this.email, required this.password});
//
//   @override
//   Widget build(BuildContext context)
//   {
//     return Scaffold(
//       appBar: AppBar(
//         title: const Text("This is Second page"),
//         centerTitle: true,
//       ),
//       body: Center(
//         child: Column(
//           mainAxisAlignment: MainAxisAlignment.center,
//           children: [
//             Text("Your details are here :",
//               style: TextStyle(
//                 fontSize: 40.0,
//                 fontWeight: FontWeight.bold,
//               ),
//             ),
//             const SizedBox(height: 30.0),
//             Row(
//               mainAxisAlignment: MainAxisAlignment.center,
//               children: [
//                 Text("Your Username is  :   ",
//                   style: TextStyle(
//                     fontWeight: FontWeight.bold,
//                     fontSize: 20.0,
//                   ),
//                 ),
//                 Text("${username}",
//                   style: TextStyle(fontSize: 20.0,),
//                 ),
//               ],
//             ),
//             const SizedBox(height: 30.0),
//             Row(
//               mainAxisAlignment: MainAxisAlignment.center,
//               children: [
//                 Text("Your Email is  :   ",
//                   style: TextStyle(
//                     fontWeight: FontWeight.bold,
//                     fontSize: 20.0,
//                   ),
//                 ),
//                 Text("${email}",
//                   style: TextStyle(fontSize: 20.0),
//                 ),
//               ],
//             ),
//             const SizedBox(height: 30.0),
//             Row(
//               mainAxisAlignment: MainAxisAlignment.center,
//               children: [
//                 Text("Your Password is  :  ",
//                   style: TextStyle(
//                     fontWeight: FontWeight.bold,
//                     fontSize: 20.0,
//                   ),
//                 ),
//                 Text("${password}",
//                   style: TextStyle(fontSize: 20.0),
//                 ),
//               ],
//             ),
//           ],
//         ),
//       ),
//     );
//   }
// }


/// EXAMPLE 2 : Using StatefulWidget as shown below
void main()
{
  runApp(MyApp());
}
class MyApp extends StatelessWidget
{
  MyApp({super.key});

  @override
  Widget build(BuildContext context)
  {
    return MaterialApp(
      title: "Data passing",
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.green,
      ),
      home: FirstDemo(),
    );
  }
}
class FirstDemo extends StatefulWidget
{
  @override
  State<FirstDemo> createState()
  {
    return FirstDemoState();
  }
}
class FirstDemoState extends State<FirstDemo>
{
  TextEditingController txt1 = new TextEditingController();
  TextEditingController txt2 = new TextEditingController();
  TextEditingController txt3 = new TextEditingController();

  @override
  Widget build(BuildContext context)
  {
    return GestureDetector(
      onTap: (){
        return FocusManager.instance.primaryFocus?.unfocus();
      },
      child: Scaffold(
        appBar: AppBar(
          title: const Text("This is First Page"),
          centerTitle: true,
        ),
        body: Center(
          child: Container(
            width: 300.0,
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                TextField(
                  controller: txt1,
                  decoration: InputDecoration(
                    hintText: "Enter the Information 1",
                    labelText: "Info 1",
                    border: OutlineInputBorder(
                      borderRadius: BorderRadius.circular(11.0),
                    ),
                  ),
                ),
                const SizedBox(height: 30.0),
                TextField(
                  controller: txt2,
                  decoration: InputDecoration(
                    hintText: "Enter the Information 2",
                    labelText: "Info 2",
                    border: OutlineInputBorder(
                      borderRadius: BorderRadius.circular(11.0),
                    ),
                  ),
                ),
                const SizedBox(height: 30.0),
                TextField(
                  controller: txt3,
                  decoration: InputDecoration(
                    hintText: "Enter the Information 3",
                    labelText: "Info 3",
                    border: OutlineInputBorder(
                      borderRadius: BorderRadius.circular(11.0),
                    ),
                  ),
                ),
                const SizedBox(height: 30.0),
                ElevatedButton(
                  onPressed: (){
                    Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context){
                          return SecondDemo(
                            txt1.text.toString(),
                            txt2.text.toString(),
                            txt3.text.toString()
                          );
                        },
                      ),
                    );
                  },
                  child: const Text("Go to Next Page"),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

class SecondDemo extends StatefulWidget
{
  String info1, info2, info3;
  SecondDemo(this.info1, this.info2, this.info3);

  @override
  State<SecondDemo> createState() => _SecondDemoState();
}

class _SecondDemoState extends State<SecondDemo> {
  @override
  Widget build(BuildContext context)
  {
    return Scaffold(
      appBar: AppBar(
        title: const Text("This is Second Page"),
        centerTitle: true,
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text("First Information is : ${widget.info1}",
              style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold),),
            const SizedBox(height: 20.0),
            Text("Second Information is : ${widget.info2}",
              style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold),),
            const SizedBox(height: 20.0),
            Text("Third Information is : ${widget.info3}",
              style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold),),
          ],
        ),
      ),
    );
  }
}