url_launcher (6.3.0+1)
Installation
dart pub add url_launcher:6.3.0+1 --hosted-url=About this package
url_launcher
A Flutter plugin for launching a URL.
| Android | iOS | Linux | macOS | Web | Windows | |
|---|---|---|---|---|---|---|
| Support | SDK 16+ | 12.0+ | Any | 10.14+ | Any | Windows 10+ |
Usage
To use this plugin, add url_launcher as a dependency in your pubspec.yaml file.
Example
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';
final Uri _url = Uri.parse('https://flutter.dev');
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');
}
}
See the example app for more complex examples.
Configuration
iOS
Add any URL schemes passed to canLaunchUrl as LSApplicationQueriesSchemes
entries in your Info.plist file, otherwise it will return false.
Example:
<key>LSApplicationQueriesSchemes</key>
<array>
<string>sms</string>
<string>tel</string>
</array>
See -[UIApplication canOpenURL:] for more details.
Android
Add any URL schemes passed to canLaunchUrl as <queries> entries in your
AndroidManifest.xml, otherwise it will return false in most cases starting
on Android 11 (API 30) or higher. Checking for
supportsLaunchMode(LaunchMode.inAppBrowserView) also requires
a <queries> entry to return anything but false. A <queries>
element must be added to your manifest as a child of the root element.
Example:
<!-- Provide required visibility configuration for API level 30 and above -->
<queries>
<!-- If your app checks for SMS support -->
<intent>
<action android:name="android.intent.action.VIEW" />
<data android:scheme="sms" />
</intent>
<!-- If your app checks for call support -->
<intent>
<action android:name="android.intent.action.VIEW" />
<data android:scheme="tel" />
</intent>
<!-- If your application checks for inAppBrowserView launch mode support -->
<intent>
<action android:name="android.support.customtabs.action.CustomTabsService" />
</intent>
</queries>
See the Android documentation for examples of other queries.
Web
Some web browsers may have limitations (e.g. a launch must be triggered by a user action). Check package:url_launcher_web for more web-specific information.
Supported URL schemes
The provided URL is passed directly to the host platform for handling. The supported URL schemes therefore depend on the platform and installed apps.
Commonly used schemes include:
| Scheme | Example | Action |
|---|---|---|
https:<URL> |
https://flutter.dev |
Open <URL> in the default browser |
mailto:<email address>?subject=<subject>&body=<body> |
mailto:smith@example.org?subject=News&body=New%20plugin |
Create email to <email address> in the default email app |
tel:<phone number> |
tel:+1-555-010-999 |
Make a phone call to <phone number> using the default phone app |
sms:<phone number> |
sms:5550101234 |
Send an SMS message to <phone number> using the default messaging app |
file:<path> |
file:/home |
Open file or folder using default app association, supported on desktop platforms |
More details can be found here for iOS and Android
URL schemes are only supported if there are apps installed on the device that can
support them. For example, iOS simulators don't have a default email or phone
apps installed, so can't open tel: or mailto: links.
Checking supported schemes
If you need to know at runtime whether a scheme is guaranteed to work before
using it (for instance, to adjust your UI based on what is available), you can
check with canLaunchUrl.
However, canLaunchUrl can return false even if launchUrl would work in
some circumstances (in web applications, on mobile without the necessary
configuration as described above, etc.), so in cases where you can provide
fallback behavior it is better to use launchUrl directly and handle failure.
For example, a UI button that would have sent feedback email using a mailto URL
might instead open a web-based feedback form using an https URL on failure,
rather than disabling the button if canLaunchUrl returns false for mailto.
Encoding URLs
URLs must be properly encoded, especially when including spaces or other special
characters. In general this is handled automatically by the
Uri class.
However, for any scheme other than http or https, you should use the
query parameter and the encodeQueryParameters function shown below rather
than Uri's queryParameters constructor argument for any query parameters,
due to a bug in the way Uri
encodes query parameters. Using queryParameters will result in spaces being
converted to + in many cases.
String? encodeQueryParameters(Map<String, String> params) {
return params.entries
.map((MapEntry<String, String> e) =>
'${Uri.encodeComponent(e.key)}=${Uri.encodeComponent(e.value)}')
.join('&');
}
// ···
final Uri emailLaunchUri = Uri(
scheme: 'mailto',
path: 'smith@example.com',
query: encodeQueryParameters(<String, String>{
'subject': 'Example Subject & Symbols are allowed!',
}),
);
launchUrl(emailLaunchUri);
Encoding for sms is slightly different:
final Uri smsLaunchUri = Uri(
scheme: 'sms',
path: '0118 999 881 999 119 7253',
queryParameters: <String, String>{
'body': Uri.encodeComponent('Example Subject & Symbols are allowed!'),
},
);
URLs not handled by Uri
In rare cases, you may need to launch a URL that the host system considers
valid, but cannot be expressed by Uri. For those cases, alternate APIs using
strings are available by importing url_launcher_string.dart.
Using these APIs in any other cases is strongly discouraged, as providing invalid URL strings was a very common source of errors with this plugin's original APIs.
File scheme handling
file: scheme can be used on desktop platforms: Windows, macOS, and Linux.
We recommend checking first whether the directory or file exists before calling launchUrl.
Example:
final String filePath = testFile.absolute.path;
final Uri uri = Uri.file(filePath);
if (!File(uri.toFilePath()).existsSync()) {
throw Exception('$uri does not exist!');
}
if (!await launchUrl(uri)) {
throw Exception('Could not launch $uri');
}
macOS file access configuration
If you need to access files outside of your application's sandbox, you will need to have the necessary entitlements.
Browser vs in-app handling
On some platforms, web URLs can be launched either in an in-app web view, or
in the default browser. The default behavior depends on the platform (see
launchUrl
for details), but a specific mode can be used on supported platforms by
passing a LaunchMode.
Platforms that do no support a requested LaunchMode will
automatically fall back to a supported mode (usually platformDefault). If
your application needs to avoid that fallback behavior, however, you can check
if the current platform supports a given mode with supportsLaunchMode before
calling launchUrl.