How can I pass arguments to the previous screen with pop()?

Question

On the screen, the user enters a message in the field and when the button is clicked, pop() fires. How can I pass the data from the field to the previous screen and display it? For implementation, I need to use pop() Screen with TextField:

// text controller for message input
  TextEditingController textController = TextEditingController();

  @override
  void dispose() {
    textController.dispose();
    super.dispose();
  }

  // go to result screen
  void getResult() {
    Navigator.pop(context, textController.text);
  }
  
  ElevatedButton(
                  onPressed: getResult, child: const Text('Display result'))

ResultScreen:

class ResultScreen extends StatefulWidget {

  @override
  State<ResultScreen> createState() => _ResultScreenState();
}

class _ResultScreenState extends State<ResultScreen> {
  @override
  Widget build(BuildContext context) {
    // navigation to text_screen
    void _navToTextScreen() {
      Navigator.push(
        context,
        MaterialPageRoute(builder: (context) => const TextScreen()),
      );
    }

    return Scaffold(
      appBar: AppBar(
        title: const Text('Results'),
      ),
      body: Center(
          child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          ElevatedButton(
            onPressed: _navToTextScreen,
            child: const Text('Enter data'),
          ),
          const SizedBox(
            height: 50
          ),
          Text('User Message:'),
          const SizedBox(
            height: 20
          ),
        ],
      )),
    );
  }
}

score 0 · Answer 1 · answered May 02 '22 at 15:54

0

await the pop and the result

Future<void> _navToTextScreen() async {
      final result = await Navigator.push(
        context,
        MaterialPageRoute(builder: (context) => const TextScreen()),
      );

answered May 02 '22 at 15:54

Mendoza

101
1
5

that's not what he asked, plz read the question again – iamdipanshus May 02 '22 at 16:05

score 0 · Answer 2 · answered May 02 '22 at 15:56

This is a working proof of concept:

import 'package:flutter/material.dart';

class FirstWidget extends StatefulWidget {
  const FirstWidget({Key? key}) : super(key: key);

  @override
  State<FirstWidget> createState() => _FirstWidgetState();
}

class _FirstWidgetState extends State<FirstWidget> {
  String text = 'Hello';
  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Text(text),
        //textbutton widget that waits for value from a new page, and when it's popped and sets it to the variable 'text'.
        TextButton(
          child: const Text('Click me'),
          onPressed: () async {
            final result = await Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => const FooWidget(),
              ),
            );
            setState(() {
              text = result;
            });
          },
        ),
      ],
    );
  }
}

class FooWidget extends StatelessWidget {
  const FooWidget({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return
    //text widget that passes it's value to the previous page.
        Column(
      children: [
        const Text('Hello'),
        TextButton(
          child: const Text('Click me'),
          onPressed: () {
            Navigator.pop(context, 'Hello from FooWidget');
          },
        ),
      ],
    );
  }
}

How can I pass arguments to the previous screen with pop()?

2 Answers2