Flutter - UIKit开发相关指南 - 导航
导航
两个页面之间切换
UIKit中,使用UINavigationController
来管理视图。Flutter中通过Navigator
和Routes
来实现相似的功能。
一个Route
是一个应用中屏幕或页的抽象,Navigator
是一个Widget来管理这些Routes
。Route
可以粗略的认为是一个UIViewController
,Navigator
类似iOS中的UINavigationController
,可以push
和pop
Routes。
切页面有两种方法
- 指定一个路由的映射表
- 直接导航到一个
Route
指定路由表 - pushName
import 'package:flutter/material.dart';
import 'package:navigation/second_route.dart';void main() {runApp(const MainApp());
}class MainApp extends StatelessWidget {const MainApp({super.key}); Widget build(BuildContext context) {return MaterialApp(title: "导航示例",home: Builder(builder:(context) => Scaffold(appBar: AppBar(title: Text("导航")),body: Center(child: ElevatedButton(onPressed: () {// 2. 跳转到SecondRouteNavigator.of(context).pushNamed('/second');},child: const Text("到第二个页面"),),),),),// 1.建立映射表 "/second"指向SecondRoute()routes: {'/second': (context) => const SecondRoute()},);}
}
import "package:flutter/cupertino.dart";
import "package:flutter/material.dart";class SecondRoute extends StatelessWidget {const SecondRoute({super.key});// 3. 显示Widget build(BuildContext context) {return Scaffold(appBar: AppBar(title: const Text("第二个路由页面")),body: Center(child: CupertinoButton(onPressed: () {// 4.点击返回Navigator.pop(context);},child: const Text("返回"),),),);}
}
返回 - pop
Flutter中使用如下代码实现pop
功能
# 或 Navigator.pop()
SystemNavigator.pop()
在iOS上约等于如下的实现
UIViewController* viewController = [UIApplication sharedApplication].keyWindow.rootViewController;
if ([viewController isKindOfClass:[UINavigationController class]]) {[((UINavigationController*)viewController) popViewControllerAnimated:NO];
}
指定路由表 - push
在push方法中直接用builder跳转,而不需要通过路由表
import 'package:flutter/material.dart';
import 'package:navigation/second_route.dart';void main() {runApp(const MainApp());
}class MainApp extends StatelessWidget {const MainApp({super.key}); Widget build(BuildContext context) {return MaterialApp(title: "导航示例",home: Builder(builder:(context) => Scaffold(appBar: AppBar(title: Text("导航")),body: Center(child: ElevatedButton(onPressed: () {// 点击直接指定跳转的界面Navigator.of(context).push(MaterialPageRoute(builder: (context) => const SecondRoute(),),);},child: const Text("到另一个页面"),),),),),);}
}
指定路由表 - go_router
go_router是一个用于Flutter声明式的路由包,使用Router API为不同屏幕间进行切换
$ flutter pub add go_router
会在pubspec.yaml
文件中添加go_router依赖包,并下载
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:navigation/second_route.dart';void main() {runApp(MaterialApp.router(title: '导航', routerConfig: _router));
}// 1.定义路由信息
final _router = GoRouter(routes: [GoRoute(path: '/', builder: (context, state) => const FirstScreen()),GoRoute(path: '/second', builder: (context, state) => const SecondRoute()),],
);class FirstScreen extends StatelessWidget {const FirstScreen({super.key}); Widget build(BuildContext context) {return Scaffold(appBar: AppBar(title: const Text('第一个界面')),body: Center(child: ElevatedButton(child: const Text('使用go_router跳转'),// 2.指定跳转界面onPressed: () => context.go('/second'),),),);}
}
import "package:flutter/cupertino.dart";
import "package:flutter/material.dart";
import "package:go_router/go_router.dart";class SecondRoute extends StatelessWidget {const SecondRoute({super.key}); Widget build(BuildContext context) {return Scaffold(appBar: AppBar(title: const Text("第二个路由页面")),body: Center(child: CupertinoButton(onPressed: () {// 3. 点击返回根目录context.go('/');},child: const Text("返回"),),),);}
}
导航到其它应用
在UIKit中使用URL scheme来实现。Flutter可以使用类似 url_launcher
的插件来实现。
Android | iOS | Linux | macOS | Web | Windows | |
---|---|---|---|---|---|---|
支持 | SDK 16+ | 12.0+ | Any | 10.14+ | Any | Window 10+ |
$ flutter pub add url_launcher
加载Web界面
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';final Uri _url = Uri.parse('https://flutter.cn');void main() => runApp(const MaterialApp(home: Material(child: Center(child: ElevatedButton(onPressed: _launchUrl,child: Text('Show Flutter homepage'),),),),),);Future<void> _launchUrl() async {if (!await launchUrl(_url)) {throw Exception('Could not launch $_url');}
}
加载其它应用
在Info.plist
添加允许打开短信和电话的配置
<key>LSApplicationQueriesSchemes</key>
<array><string>sms</string><string>tel</string>
</array>
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';final Uri _url = Uri.parse('tel://10000');void main() => runApp(const MaterialApp(home: Material(child: Center(child: ElevatedButton(// 1. 绑定对应方法onPressed: _launchUrl,child: Text('Show Flutter homepage'),),),),),
);Future<void> _launchUrl() async {// 2. 确认是否能打开对应url,已添加到plist文件if (await canLaunchUrl(_url)) {if (!await launchUrl(_url)) {throw Exception('Could not launch $_url');}}
}
参考
- 给 UIKit 开发者的 Flutter 指南
- url_launcher