DropdownButton in Flutter

DropdownButton widget is used to create a dropdown menu. A dropdown menu allows users to select a single item from a list of options.

There Are Some Common Attributes for DropdownButton

Here's a simple example of using a DropdownButton in Flutter:

File open lib->main.dart file −

import 'package:flutter/material.dart';

void main() {
  runApp(
    MyApp()
  );
}
class MyApp extends StatefulWidget{

  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
   String _selectedItem="Flutter";

  // List of items for the dropdown
  List<String> _items = ['Flutter', 'Java', 'Kotlin', 'JetPack'];
  @override
  Widget build(BuildContext context) {
    return   MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          backgroundColor: Colors.blue,
          title: Text('DropdownButton Example',
              style:TextStyle(fontSize: 20,color: Colors.white)),
        ),
        body:
        Center(

          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            crossAxisAlignment: CrossAxisAlignment.center,
            children: [

              DropdownButton(
                value: _selectedItem,
                items: _items.map((String item) {
                  return DropdownMenuItem(
                    value: item,
                    child: Text(item),
                  );
                }).toList(),
                onChanged: (value) {
                  setState(() {
                    _selectedItem = value!;
                  });
                },
              ),
              SizedBox(height: 20),
              Text('Selected Item: $_selectedItem'),
            ],
          ),
        )

    ));

  }
}

Open Device Manager, run the emulator, and then run the application. Next, check the working output and check the output you declared in your code.

Output: