react-native/website/versioned_docs/0.21/linking.md

---
id: version-0.21-linking
title: linking
original_id: linking
---
<a id="content"></a><table width="100%"><tbody><tr><td><h1><a class="anchor" name="linking"></a>Linking <a class="hash-link" href="undefined#linking">#</a></h1></td><td style="text-align:right;"><a target="_blank" href="https://github.com/facebook/react-native/blob/master/Libraries/Linking/Linking.js">Edit on GitHub</a></td></tr></tbody></table><div><div><p><code>Linking</code> gives you a general interface to interact with both incoming
and outgoing app links.</p><h3><a class="anchor" name="basic-usage"></a>Basic Usage <a class="hash-link" href="undefined#basic-usage">#</a></h3><h4><a class="anchor" name="handling-deep-links"></a>Handling deep links <a class="hash-link" href="undefined#handling-deep-links">#</a></h4><p>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</p><div class="prism language-javascript"><span class="token function">componentDidMount<span class="token punctuation">(</span></span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  <span class="token keyword">var</span> url <span class="token operator">=</span> Linking<span class="token punctuation">.</span><span class="token function">getInitialURL<span class="token punctuation">(</span></span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">then<span class="token punctuation">(</span></span><span class="token punctuation">(</span>url<span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>url<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      console<span class="token punctuation">.</span><span class="token function">log<span class="token punctuation">(</span></span><span class="token string">'Initial url is: '</span> <span class="token operator">+</span> url<span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token keyword">catch</span><span class="token punctuation">(</span>err <span class="token operator">=</span><span class="token operator">&gt;</span> console<span class="token punctuation">.</span><span class="token function">error<span class="token punctuation">(</span></span><span class="token string">'An error occurred'</span><span class="token punctuation">,</span> err<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span></div><p>NOTE: For instructions on how to add support for deep linking on Android,
refer <a href="http://developer.android.com/training/app-indexing/deep-linking.html#adding-filters" target="_blank">Enabling Deep Links for App Content - Add Intent Filters for Your Deep Links</a>.</p><p>NOTE: For iOS, in case you also want to listen to incoming app links during your app's
execution you'll need to add the following lines to you <code>*AppDelegate.m</code>:</p><div class="prism language-javascript">#import <span class="token string">"RCTLinkingManager.h"</span>

<span class="token operator">-</span> <span class="token punctuation">(</span>BOOL<span class="token punctuation">)</span>application<span class="token punctuation">:</span><span class="token punctuation">(</span>UIApplication <span class="token operator">*</span><span class="token punctuation">)</span>application openURL<span class="token punctuation">:</span><span class="token punctuation">(</span>NSURL <span class="token operator">*</span><span class="token punctuation">)</span>url
  sourceApplication<span class="token punctuation">:</span><span class="token punctuation">(</span>NSString <span class="token operator">*</span><span class="token punctuation">)</span>sourceApplication annotation<span class="token punctuation">:</span><span class="token punctuation">(</span>id<span class="token punctuation">)</span>annotation
<span class="token punctuation">{</span>
  <span class="token keyword">return</span> <span class="token punctuation">[</span>RCTLinkingManager application<span class="token punctuation">:</span>application openURL<span class="token punctuation">:</span>url
                      sourceApplication<span class="token punctuation">:</span>sourceApplication annotation<span class="token punctuation">:</span>annotation<span class="token punctuation">]</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token comment" spellcheck="true">
// Only if your app is using [Universal Links](https://developer.apple.com/library/prerelease/ios/documentation/General/Conceptual/AppSearch/UniversalLinks.html).
</span><span class="token operator">-</span> <span class="token punctuation">(</span>BOOL<span class="token punctuation">)</span>application<span class="token punctuation">:</span><span class="token punctuation">(</span>UIApplication <span class="token operator">*</span><span class="token punctuation">)</span>application continueUserActivity<span class="token punctuation">:</span><span class="token punctuation">(</span>NSUserActivity <span class="token operator">*</span><span class="token punctuation">)</span>userActivity
 restorationHandler<span class="token punctuation">:</span><span class="token punctuation">(</span>void <span class="token punctuation">(</span><span class="token operator">^</span><span class="token punctuation">)</span><span class="token punctuation">(</span>NSArray <span class="token operator">*</span> _Nullable<span class="token punctuation">)</span><span class="token punctuation">)</span>restorationHandler
<span class="token punctuation">{</span>
 <span class="token keyword">return</span> <span class="token punctuation">[</span>RCTLinkingManager application<span class="token punctuation">:</span>application
                  continueUserActivity<span class="token punctuation">:</span>userActivity
                    restorationHandler<span class="token punctuation">:</span>restorationHandler<span class="token punctuation">]</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span></div><p>And then on your React component you'll be able to listen to the events on
<code>Linking</code> as follows</p><div class="prism language-javascript"><span class="token function">componentDidMount<span class="token punctuation">(</span></span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  Linking<span class="token punctuation">.</span><span class="token function">addEventListener<span class="token punctuation">(</span></span><span class="token string">'url'</span><span class="token punctuation">,</span> <span class="token keyword">this</span><span class="token punctuation">.</span>_handleOpenURL<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span><span class="token punctuation">,</span>
<span class="token function">componentWillUnmount<span class="token punctuation">(</span></span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  Linking<span class="token punctuation">.</span><span class="token function">removeEventListener<span class="token punctuation">(</span></span><span class="token string">'url'</span><span class="token punctuation">,</span> <span class="token keyword">this</span><span class="token punctuation">.</span>_handleOpenURL<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span><span class="token punctuation">,</span>
<span class="token function">_handleOpenURL<span class="token punctuation">(</span></span>event<span class="token punctuation">)</span> <span class="token punctuation">{</span>
  console<span class="token punctuation">.</span><span class="token function">log<span class="token punctuation">(</span></span>event<span class="token punctuation">.</span>url<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span></div><p>Note that this is only supported on iOS.</p><h4><a class="anchor" name="opening-external-links"></a>Opening external links <a class="hash-link" href="undefined#opening-external-links">#</a></h4><p>To start the corresponding activity for a link (web URL, email, contact etc.), call</p><div class="prism language-javascript">Linking<span class="token punctuation">.</span><span class="token function">openURL<span class="token punctuation">(</span></span>url<span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token keyword">catch</span><span class="token punctuation">(</span>err <span class="token operator">=</span><span class="token operator">&gt;</span> console<span class="token punctuation">.</span><span class="token function">error<span class="token punctuation">(</span></span><span class="token string">'An error occurred'</span><span class="token punctuation">,</span> err<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span></div><p>If you want to check if any installed app can handle a given URL beforehand you can call</p><div class="prism language-javascript">Linking<span class="token punctuation">.</span><span class="token function">canOpenURL<span class="token punctuation">(</span></span>url<span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">then<span class="token punctuation">(</span></span>supported <span class="token operator">=</span><span class="token operator">&gt;</span> <span class="token punctuation">{</span>
  <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>supported<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    console<span class="token punctuation">.</span><span class="token function">log<span class="token punctuation">(</span></span><span class="token string">'Can\'t handle url: '</span> <span class="token operator">+</span> url<span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> Linking<span class="token punctuation">.</span><span class="token function">openURL<span class="token punctuation">(</span></span>url<span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token keyword">catch</span><span class="token punctuation">(</span>err <span class="token operator">=</span><span class="token operator">&gt;</span> console<span class="token punctuation">.</span><span class="token function">error<span class="token punctuation">(</span></span><span class="token string">'An error occurred'</span><span class="token punctuation">,</span> err<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span></div></div><span><h3><a class="anchor" name="methods"></a>Methods <a class="hash-link" href="undefined#methods">#</a></h3><div class="props"><div class="prop"><h4 class="propTitle"><a class="anchor" name="addeventlistener"></a><span class="propType">static </span>addEventListener<span class="propType">(type: string, handler: Function)</span> <a class="hash-link" href="undefined#addeventlistener">#</a></h4><div><p>Add a handler to Linking changes by listening to the <code>url</code> event type
and providing the handler</p><p>@platform ios</p></div></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="removeeventlistener"></a><span class="propType">static </span>removeEventListener<span class="propType">(type: string, handler: Function)</span> <a class="hash-link" href="undefined#removeeventlistener">#</a></h4><div><p>Remove a handler by passing the <code>url</code> event type and the handler</p><p>@platform ios</p></div></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="openurl"></a><span class="propType">static </span>openURL<span class="propType">(url: string)</span> <a class="hash-link" href="undefined#openurl">#</a></h4><div><p>Try to open the given <code>url</code> with any of the installed apps.</p><p>You can use other URLs, like a location (e.g. "geo:37.484847,-122.148386"), a contact,
or any other URL that can be opened with the installed apps.</p><p>NOTE: 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.</p><p>NOTE: For web URLs, the protocol ("http://", "https://") must be set accordingly!</p></div></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="canopenurl"></a><span class="propType">static </span>canOpenURL<span class="propType">(url: string)</span> <a class="hash-link" href="undefined#canopenurl">#</a></h4><div><p>Determine whether or not an installed app can handle a given URL.</p><p>NOTE: For web URLs, the protocol ("http://", "https://") must be set accordingly!</p><p>NOTE: As of iOS 9, your app needs to provide the <code>LSApplicationQueriesSchemes</code> key
inside <code>Info.plist</code>.</p><p>@param URL the URL to open</p></div></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="getinitialurl"></a><span class="propType">static </span>getInitialURL<span class="propType">()</span> <a class="hash-link" href="undefined#getinitialurl">#</a></h4><div><p>If the app launch was triggered by an app link with,
it will give the link url, otherwise it will give <code>null</code></p><p>NOTE: To support deep linking on Android, refer <a href="http://developer.android.com/training/app-indexing/deep-linking.html#handling-intents">http://developer.android.com/training/app-indexing/deep-linking.html#handling-intents</a></p></div></div></div></span></div><div class="docs-prevnext"><a class="docs-next" href="linkingios.html#content">Next →</a></div>