Linking

Linking gives you a general interface to interact with both incoming and outgoing app links.

Basic Usage

Handling deep links

If your app was launched from an external url registered to your app you can access and handle it from any component you want with

componentDidMount() {
  Linking.getInitialURL().then((url) => {
    if (url) {
      console.log('Initial url is: ' + url);
    }
  }).catch(err => console.error('An error occurred', err));
}

For instructions on how to add support for deep linking on Android, refer to Enabling Deep Links for App Content - Add Intent Filters for Your Deep Links.

If you wish to receive the intent in an existing instance of MainActivity, you may set the launchMode of MainActivity to singleTask in AndroidManifest.xml. See <activity> documentation for more information.

<activity
  android:name=".MainActivity"
  android:launchMode="singleTask">

NOTE: On iOS, you'll need to link RCTLinking to your project by following the steps described here. If you also want to listen to incoming app links during your app's execution, you'll need to add the following lines to your *AppDelegate.m:

// iOS 9.x or newer
#import <React/RCTLinkingManager.h>

- (BOOL)application:(UIApplication *)application
   openURL:(NSURL *)url
   options:(NSDictionary<UIApplicationOpenURLOptionsKey,id> *)options
{
  return [RCTLinkingManager application:application openURL:url options:options];
}

If you're targeting iOS 8.x or older, you can use the following code instead:

// iOS 8.x or older
#import <React/RCTLinkingManager.h>

- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url
  sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
  return [RCTLinkingManager application:application openURL:url
                      sourceApplication:sourceApplication annotation:annotation];
}

If your app is using Universal Links, you'll need to add the following code as well:

- (BOOL)application:(UIApplication *)application continueUserActivity:(NSUserActivity *)userActivity
 restorationHandler:(void (^)(NSArray * _Nullable))restorationHandler
{
 return [RCTLinkingManager application:application
                  continueUserActivity:userActivity
                    restorationHandler:restorationHandler];
}

And then on your React component you'll be able to listen to the events on Linking as follows

componentDidMount() {
  Linking.addEventListener('url', this._handleOpenURL);
},
componentWillUnmount() {
  Linking.removeEventListener('url', this._handleOpenURL);
},
_handleOpenURL(event) {
  console.log(event.url);
}

Opening external links

To start the corresponding activity for a link (web URL, email, contact etc.), call

Linking.openURL(url).catch(err => console.error('An error occurred', err));

If you want to check if any installed app can handle a given URL beforehand you can call

Linking.canOpenURL(url).then(supported => {
  if (!supported) {
    console.log('Can\'t handle url: ' + url);
  } else {
    return Linking.openURL(url);
  }
}).catch(err => console.error('An error occurred', err));

Methods

• constructor
• addEventListener
• removeEventListener
• openURL
• canOpenURL
• getInitialURL

Reference

Methods

constructor()

constructor();

addEventListener()

addEventListener(type, handler);

Add a handler to Linking changes by listening to the url event type and providing the handler

removeEventListener()

removeEventListener(type, handler);

Remove a handler by passing the url event type and the handler

openURL()

openURL(url);

Try to open the given url with any of the installed apps.

You can use other URLs, like a location (e.g. "geo:37.484847,-122.148386" on Android or "http://maps.apple.com/?ll=37.484847,-122.148386" on iOS), a contact, or any other URL that can be opened with the installed apps.

The method returns a Promise object. If the user confirms the open dialog or the url automatically opens, the promise is resolved. If the user cancels the open dialog or there are no registered applications for the url, the promise is rejected.

Parameters:

Name	Type	Required	Description
url	string	Yes	The URL to open.

This method will fail if the system doesn't know how to open the specified URL. If you're passing in a non-http(s) URL, it's best to check {@code canOpenURL} first.

For web URLs, the protocol ("http://", "https://") must be set accordingly!

canOpenURL()

canOpenURL(url);

Determine whether or not an installed app can handle a given URL.

The method returns a Promise object. When it is determined whether or not the given URL can be handled, the promise is resolved and the first parameter is whether or not it can be opened.

Parameters:

Name	Type	Required	Description
url	string	Yes	The URL to open.

For web URLs, the protocol ("http://", "https://") must be set accordingly!

As of iOS 9, your app needs to provide the LSApplicationQueriesSchemes key inside Info.plist or canOpenURL will always return false.

getInitialURL()

getInitialURL();

If the app launch was triggered by an app link, it will give the link url, otherwise it will give null

To support deep linking on Android, refer http://developer.android.com/training/app-indexing/deep-linking.html#handling-intents