In this tutorial you will learn how to launch a web app using the URL launcher plugin. This is one of the most popular flutter plugins and such an action as launching a website from an app is quite common.
What is URL Launcher?
It is a Flutter plugin for launching a URL. Supports iOS, Android, web, Windows, macOS, and Linux.
Here are the steps to follow to use it.
Step 1: Install it
It's installation is very simple. Simply navigate over to your pubspec.yaml
and add it as a dependency:
dependencies:
url_launcher: ^6.0.9
Then sync or flutter pub get
to fetch it.
Step 2: Configure your app
Now that you've installed the package.
iOS
If you are using iOS, then any URL schemes passed to canLaunch
as LSApplicationQueriesSchemes
entries in your Info.plist file:
<key>LSApplicationQueriesSchemes</key>
<array>
<string>https</string>
<string>http</string>
</array>
Android
Starting from API 30 Android requires package visibility configuration in your AndroidManifest.xml
otherwise canLaunch
will return false
. A <queries>
element must be added to your manifest as a child of the root element.
<queries>
<!-- If your app opens https URLs -->
<intent>
<action android:name="android.intent.action.VIEW" />
<data android:scheme="https" />
</intent>
<!-- If your app makes calls -->
<intent>
<action android:name="android.intent.action.DIAL" />
<data android:scheme="tel" />
</intent>
<!-- If your app emails -->
<intent>
<action android:name="android.intent.action.SEND" />
<data android:mimeType="*/*" />
</intent>
</queries>
Step 3: Write Code
First of course you need to import it into your dart
file:
import 'package:url_launcher/url_launcher.dart';
Then for example if you want to launch webview with Javascript:
Future<void> _launchInWebViewWithJavaScript(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
enableJavaScript: true,
);
} else {
throw 'Could not launch $url';
}
}
And if you want to launch webview with DOm stroage:
Future<void> _launchInWebViewWithDomStorage(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
enableDomStorage: true,
);
} else {
throw 'Could not launch $url';
}
}
Then follow the following example to understand how to use this package:
main.dart
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:url_launcher/link.dart';
import 'package:url_launcher/url_launcher.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'URL Launcher',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'URL Launcher'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
Future<void>? _launched;
String _phone = '';
Future<void> _launchInBrowser(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: false,
forceWebView: false,
headers: <String, String>{'my_header_key': 'my_header_value'},
);
} else {
throw 'Could not launch $url';
}
}
Future<void> _launchInWebViewOrVC(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
headers: <String, String>{'my_header_key': 'my_header_value'},
);
} else {
throw 'Could not launch $url';
}
}
Future<void> _launchInWebViewWithJavaScript(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
enableJavaScript: true,
);
} else {
throw 'Could not launch $url';
}
}
Future<void> _launchInWebViewWithDomStorage(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
enableDomStorage: true,
);
} else {
throw 'Could not launch $url';
}
}
Future<void> _launchUniversalLinkIos(String url) async {
if (await canLaunch(url)) {
final bool nativeAppLaunchSucceeded = await launch(
url,
forceSafariVC: false,
universalLinksOnly: true,
);
if (!nativeAppLaunchSucceeded) {
await launch(
url,
forceSafariVC: true,
);
}
}
}
Widget _launchStatus(BuildContext context, AsyncSnapshot<void> snapshot) {
if (snapshot.hasError) {
return Text('Error: ${snapshot.error}');
} else {
return const Text('');
}
}
Future<void> _makePhoneCall(String url) async {
if (await canLaunch(url)) {
await launch(url);
} else {
throw 'Could not launch $url';
}
}
@override
Widget build(BuildContext context) {
const String toLaunch = 'https://www.cylog.org/headers/';
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: ListView(
children: <Widget>[
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(16.0),
child: TextField(
onChanged: (String text) => _phone = text,
decoration: const InputDecoration(
hintText: 'Input the phone number to launch')),
),
ElevatedButton(
onPressed: () => setState(() {
_launched = _makePhoneCall('tel:$_phone');
}),
child: const Text('Make phone call'),
),
const Padding(
padding: EdgeInsets.all(16.0),
child: Text(toLaunch),
),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchInBrowser(toLaunch);
}),
child: const Text('Launch in browser'),
),
const Padding(padding: EdgeInsets.all(16.0)),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchInWebViewOrVC(toLaunch);
}),
child: const Text('Launch in app'),
),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchInWebViewWithJavaScript(toLaunch);
}),
child: const Text('Launch in app(JavaScript ON)'),
),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchInWebViewWithDomStorage(toLaunch);
}),
child: const Text('Launch in app(DOM storage ON)'),
),
const Padding(padding: EdgeInsets.all(16.0)),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchUniversalLinkIos(toLaunch);
}),
child: const Text(
'Launch a universal link in a native app, fallback to Safari.(Youtube)'),
),
const Padding(padding: EdgeInsets.all(16.0)),
ElevatedButton(
onPressed: () => setState(() {
_launched = _launchInWebViewOrVC(toLaunch);
Timer(const Duration(seconds: 5), () {
print('Closing WebView after 5 seconds...');
closeWebView();
});
}),
child: const Text('Launch in app + close after 5 seconds'),
),
const Padding(padding: EdgeInsets.all(16.0)),
Link(
uri: Uri.parse(
'https://pub.dev/documentation/url_launcher/latest/link/link-library.html'),
target: LinkTarget.blank,
builder: (ctx, openLink) {
return TextButton.icon(
onPressed: openLink,
label: Text('Link Widget documentation'),
icon: Icon(Icons.read_more),
);
},
),
const Padding(padding: EdgeInsets.all(16.0)),
FutureBuilder<void>(future: _launched, builder: _launchStatus),
],
),
],
),
);
}
}
Reference
Here are the reference links:
Number | Link |
---|---|
1. | Download code |
2. | Read more |