| 1 | // Copyright 2014 The Flutter Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | import 'package:flutter/material.dart'; |
| 6 | |
| 7 | /// Flutter code sample for [DropdownButton.style]. |
| 8 | |
| 9 | void main() => runApp(const DropdownButtonApp()); |
| 10 | |
| 11 | class DropdownButtonApp extends StatelessWidget { |
| 12 | const DropdownButtonApp({super.key}); |
| 13 | |
| 14 | @override |
| 15 | Widget build(BuildContext context) { |
| 16 | return MaterialApp( |
| 17 | home: Scaffold( |
| 18 | appBar: AppBar(title: const Text('DropdownButton Sample')), |
| 19 | body: const DropdownButtonExample(), |
| 20 | ), |
| 21 | ); |
| 22 | } |
| 23 | } |
| 24 | |
| 25 | class DropdownButtonExample extends StatefulWidget { |
| 26 | const DropdownButtonExample({super.key}); |
| 27 | |
| 28 | @override |
| 29 | State<DropdownButtonExample> createState() => _DropdownButtonExampleState(); |
| 30 | } |
| 31 | |
| 32 | class _DropdownButtonExampleState extends State<DropdownButtonExample> { |
| 33 | List<String> options = <String>['One', 'Two', 'Three', 'Four']; |
| 34 | String dropdownValue = 'One'; |
| 35 | |
| 36 | @override |
| 37 | Widget build(BuildContext context) { |
| 38 | return Container( |
| 39 | alignment: Alignment.center, |
| 40 | color: Colors.blue, |
| 41 | child: DropdownButton<String>( |
| 42 | value: dropdownValue, |
| 43 | onChanged: (String? value) { |
| 44 | // This is called when the user selects an item. |
| 45 | setState(() { |
| 46 | dropdownValue = value!; |
| 47 | }); |
| 48 | }, |
| 49 | style: const TextStyle(color: Colors.blue), |
| 50 | selectedItemBuilder: (BuildContext context) { |
| 51 | // This is the widget that will be shown when you select an item. |
| 52 | // Here custom text style, alignment and layout size can be applied |
| 53 | // to selected item string. |
| 54 | return options.map((String value) { |
| 55 | return Align( |
| 56 | alignment: Alignment.centerLeft, |
| 57 | child: Text(dropdownValue, style: const TextStyle(color: Colors.white)), |
| 58 | ); |
| 59 | }).toList(); |
| 60 | }, |
| 61 | items: |
| 62 | options.map<DropdownMenuItem<String>>((String value) { |
| 63 | return DropdownMenuItem<String>(value: value, child: Text(value)); |
| 64 | }).toList(), |
| 65 | ), |
| 66 | ); |
| 67 | } |
| 68 | } |
| 69 |