Flutter区域与国家下拉菜单插件region_and_country_dropdown的使用
Flutter区域与国家下拉菜单插件region_and_country_dropdown的使用
Flutter插件 region_and_country_dropdown 可以帮助您在表单中选择国家和地区。以下是该插件的使用方法和完整示例。
开始使用
获取插件
在您的 pubspec.yaml 文件中添加以下依赖：
dependencies:
region_and_country_dropdown: ^版本号
然后运行以下命令以安装依赖：
flutter pub get
示例代码
以下是一个完整的示例代码，展示了如何使用 region_and_country_dropdown 插件。
示例代码
import 'package:flutter/material.dart';
import 'package:region_and_country_dropdown/models/country_model.dart';
import 'package:region_and_country_dropdown/models/region_model.dart';
import 'package:region_and_country_dropdown/widgets/country_dropdown.dart';
import 'package:region_and_country_dropdown/widgets/region_and_country_provider_sate.dart';
import 'package:region_and_country_dropdown/widgets/region_dropdown.dart';
void main() {
runApp(const RegionAndCountryProviderState(child: MyApp()));
}
class MyApp extends StatefulWidget {
const MyApp({super.key});
[@override](/user/override)
State<MyApp> createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
bool _countryError = false;
bool _regionError = false;
bool _countryCombinedWithRegionError = false;
bool _regionCombinedWithCountryError = false;
RegionModel? _selectedRegion;
CountryModel? _selectedCountryCombinedWithRegion;
RegionModel? _selectedRegionCombinedWithCountry;
CountryModel? _selectedCountryWithError;
RegionModel? _selectedRegionWithError;
CountryModel? _selectedCountryCombinedWithRegionWithError;
RegionModel? _selectedRegionCombinedWithCountryWithError;
[@override](/user/override)
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
appBar: AppBar(
title: const Text('插件示例应用'),
),
body: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
singleCountryDropdownExample(context),
singleRegionDropdownExample(),
countryCombinedWithRegionExample(),
singleCountryWithErrorHandlingExample(),
singleRegionWithErrorHandlingExample(),
countryCombinedWithRegionErrorHandlingExample()
],
),
),
),
);
}
Widget singleCountryDropdownExample(BuildContext context) {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text('仅包含国家下拉菜单的示例'),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {},
selectedItem: CountryModel.fromTranslatedName("科特迪瓦", context, 'fr'),
)),
],
);
}
Widget singleRegionDropdownExample() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text('仅包含地区下拉菜单的示例'),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: RegionDropdown(
onChanged: (RegionModel? region) async {
setState(() {
_selectedRegion = region;
});
},
selectedItem: _selectedRegion,
)),
],
);
}
Widget countryCombinedWithRegionExample() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text('混合国家和地区下拉菜单的示例'),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {
setState(() {
_selectedCountryCombinedWithRegion = country;
_selectedRegionCombinedWithCountry = null;
});
},
)),
Padding(
padding: const EdgeInsets.all(8.0),
child: RegionDropdown(
onChanged: (RegionModel? region) async {
setState(() {
_selectedRegionCombinedWithCountry = region;
});
},
selectedCountry: _selectedCountryCombinedWithRegion,
selectedItem: _selectedRegionCombinedWithCountry,
dependsOnTheChosenCountry: true,
)),
],
);
}
Widget singleCountryWithErrorHandlingExample() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text('带错误处理的国家下拉菜单示例'),
),
_countryError
? Padding(
padding: const EdgeInsets.all(8.0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {
setState(() {
_selectedCountryWithError = country;
_countryError = false;
});
},
requiredErrorMessage: '国家是必填项',
boxDecoration: BoxDecoration(
border: Border.all(color: Theme.of(context).errorColor),
borderRadius: const BorderRadius.all(Radius.circular(5))),
))
: Padding(
padding: const EdgeInsets.only(
top: 8.0, left: 8.0, right: 8.0, bottom: 0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {
setState(() {
_selectedCountryWithError = country;
});
},
)),
Padding(
padding:
const EdgeInsets.only(left: 8.0, right: 8.0, bottom: 8.0, top: 0),
child: ElevatedButton(
child: const Text('提交'),
onPressed: () {
if (_selectedCountryWithError == null) {
setState(() {
_countryError = true;
});
}
},
),
),
],
);
}
Widget singleRegionWithErrorHandlingExample() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text('带错误处理的地区下拉菜单示例'),
),
_regionError
? Padding(
padding: const EdgeInsets.all(8.0),
child: RegionDropdown(
onChanged: (RegionModel? country) async {
setState(() {
_selectedRegionWithError = country;
_regionError = false;
});
},
requiredErrorMessage: '地区是必填项',
boxDecoration: BoxDecoration(
border: Border.all(color: Theme.of(context).errorColor),
borderRadius: const BorderRadius.all(Radius.circular(5))),
selectedItem: _selectedRegionWithError,
))
: Padding(
padding: const EdgeInsets.only(
top: 8.0, left: 8.0, right: 8.0, bottom: 0),
child: RegionDropdown(
onChanged: (RegionModel? region) async {
setState(() {
_selectedRegionWithError = region;
});
},
selectedItem: _selectedRegionWithError,
)),
Padding(
padding: const EdgeInsets.all(10.0),
child: ElevatedButton(
child: const Text('提交'),
onPressed: () {
if (_selectedRegionWithError == null) {
setState(() {
_regionError = true;
});
}
},
),
)
],
);
}
Widget countryCombinedWithRegionErrorHandlingExample() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Padding(
padding: EdgeInsets.all(10.0),
child: Text(
'混合国家和地区下拉菜单的错误处理示例'),
),
_countryCombinedWithRegionError
? Padding(
padding: const EdgeInsets.all(8.0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {
setState(() {
_selectedCountryCombinedWithRegionWithError = country;
_countryCombinedWithRegionError = false;
});
},
requiredErrorMessage: '国家是必填项',
boxDecoration: BoxDecoration(
border: Border.all(color: Theme.of(context).errorColor),
borderRadius: const BorderRadius.all(Radius.circular(5))),
))
: Padding(
padding: const EdgeInsets.only(
top: 8.0, left: 8.0, right: 8.0, bottom: 0),
child: CountryDropdown(
onChanged: (CountryModel? country) async {
setState(() {
_selectedCountryCombinedWithRegionWithError = country;
});
},
)),
_regionCombinedWithCountryError
? Padding(
padding: const EdgeInsets.all(8.0),
child: RegionDropdown(
onChanged: (RegionModel? region) async {
setState(() {
_selectedRegionCombinedWithCountryWithError = region;
_regionCombinedWithCountryError = false;
});
},
dependsOnTheChosenCountry: true,
requiredErrorMessage: '地区是必填项',
selectedItem: _selectedRegionCombinedWithCountryWithError,
selectedCountry: _selectedCountryCombinedWithRegionWithError,
boxDecoration: BoxDecoration(
border: Border.all(color: Theme.of(context).errorColor),
borderRadius: const BorderRadius.all(Radius.circular(5))),
))
: Padding(
padding: const EdgeInsets.only(
top: 8.0, left: 8.0, right: 8.0, bottom: 0),
child: RegionDropdown(
onChanged: (RegionModel? region) async {
setState(() {
_selectedRegionCombinedWithCountryWithError = region;
});
},
selectedItem: _selectedRegionCombinedWithCountryWithError,
selectedCountry: _selectedCountryCombinedWithRegionWithError,
dependsOnTheChosenCountry: true,
)),
Padding(
padding: const EdgeInsets.only(
left: 8.0, right: 8.0, bottom: 8.0, top: 10.0),
child: ElevatedButton(
child: const Text('提交'),
onPressed: () {
if (_selectedCountryCombinedWithRegionWithError == null) {
setState(() {
_countryCombinedWithRegionError = true;
});
}
if (_selectedRegionCombinedWithCountryWithError == null) {
setState(() {
_regionCombinedWithCountryError = true;
});
}
},
),
),
],
);
}
}
更多关于Flutter区域与国家下拉菜单插件region_and_country_dropdown的使用的实战教程也可以访问 https://www.itying.com/category-92-b0.html
1 回复
更多关于Flutter区域与国家下拉菜单插件region_and_country_dropdown的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
region_and_country_dropdown 是一个 Flutter 插件，用于在应用程序中显示区域和国家（Region and Country）的下拉菜单。它可以帮助用户从预定义的列表中选择区域和国家。以下是如何在 Flutter 项目中使用 region_and_country_dropdown 插件的步骤：
1. 添加依赖
首先，你需要在 pubspec.yaml 文件中添加 region_and_country_dropdown 插件的依赖。
dependencies:
flutter:
sdk: flutter
region_and_country_dropdown: ^1.0.0 # 请使用最新版本
然后运行 flutter pub get 来获取依赖包。
2. 导入插件
在你的 Dart 文件中导入插件：
import 'package:region_and_country_dropdown/region_and_country_dropdown.dart';
3. 使用 RegionAndCountryDropdown
你可以在你的 Flutter 应用中使用 RegionAndCountryDropdown 小部件来显示区域和国家的下拉菜单。
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
String? selectedRegion;
String? selectedCountry;
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Region and Country Dropdown Example'),
),
body: Padding(
padding: const EdgeInsets.all(16.0),
child: Column(
children: [
RegionAndCountryDropdown(
onRegionChanged: (String? region) {
setState(() {
selectedRegion = region;
});
},
onCountryChanged: (String? country) {
setState(() {
selectedCountry = country;
});
},
),
SizedBox(height: 20),
Text('Selected Region: $selectedRegion'),
Text('Selected Country: $selectedCountry'),
],
),
),
);
}
}
4. 运行应用
现在你可以运行你的 Flutter 应用，并查看 RegionAndCountryDropdown 小部件的行为。用户可以选择区域和国家，你可以在 onRegionChanged 和 onCountryChanged 回调中获取用户选择的值。
5. 自定义选项
RegionAndCountryDropdown 小部件还提供了一些可选参数，允许你自定义下拉菜单的行为和外观。例如，你可以设置默认选择的区域和国家，或者自定义下拉菜单的样式。
RegionAndCountryDropdown(
initialRegion: 'Asia', // 设置默认选择的区域
initialCountry: 'India', // 设置默认选择的国家
onRegionChanged: (String? region) {
setState(() {
selectedRegion = region;
});
},
onCountryChanged: (String? country) {
setState(() {
selectedCountry = country;
});
},
dropdownDecoration: InputDecoration(
labelText: 'Select Region and Country',
border: OutlineInputBorder(),
),
)