How to add DropdownButton in AppBar in Flutter

In this Google flutter code example we are going to learn how to add dropdownbutton in AppBar in flutter.

The code is based on flutter version 1.0.0

Main.dart (App entry point)

import 'package:flutter/material.dart';
import 'dropdownbutton_appbar.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      //home: MyHomePage(title: 'Flutter Demo Home Page'),
      home: KeyValuePairDropdown(),
    );
  }
}
dropdownbutton_appbar.dart
import 'package:flutter/material.dart';

class KeyValuePairDropdown extends StatefulWidget {
  @override
  KeyValuePairDropdownState createState() {
    return new KeyValuePairDropdownState();
  }
}

class KeyValuePairDropdownState extends State<KeyValuePairDropdown> {
  final List<String> _dropdownValues = [
    "One",
    "Two",
    "Three",
    "Four",
    "Five"
  ]; //The list of values we want on the dropdown
  String _currentlySelected = ""; //var to hold currently selected value

  //make the drop down its own widget for readability
  Widget dropdownWidget() {
    return DropdownButton(
      //map each value from the lIst to our dropdownMenuItem widget
      items: _dropdownValues
          .map((value) => DropdownMenuItem(
                child: Text(value),
                value: value,
              ))
          .toList(),
      onChanged: (String value) {
        //once dropdown changes, update the state of out currentValue
        setState(() {
          _currentlySelected = value;
        });
      },
      //this wont make dropdown expanded and fill the horizontal space
      isExpanded: false,
      //make default value of dropdown the first value of our list
      value: _dropdownValues.first,
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('DropdownButton in AppBar'),
        actions: <Widget>[
          //Add the dropdown widget to the `Action` part of our appBar. it can also be among the `leading` part
          dropdownWidget(),
        ],
      ),
      //display currently selected item on dropdown
      body: Center(child: Text(_currentlySelected)),
    );
  }
}

flutter dropdownbutton in appbar

If you have any questions or suggestions kindly use the comment box or you can contact us directly through our contact page below.

 

Add a Comment