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<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Headless JS · React Native</title><meta name="viewport" content="width=device-width"/><meta name="generator" content="Docusaurus"/><meta name="description" content="Headless JS is a way to run tasks in JavaScript while your app is in the background. It can be used, for example, to sync fresh data, handle push notifications, or play music."/><meta name="docsearch:version" content="0.52"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Headless JS · React Native"/><meta property="og:type" content="website"/><meta property="og:url" content="https://reactnative.dev/"/><meta property="og:description" content="Headless JS is a way to run tasks in JavaScript while your app is in the background. It can be used, for example, to sync fresh data, handle push notifications, or play music."/><meta property="og:image" content="https://reactnative.dev/img/logo-og.png"/><meta name="twitter:card" content="summary"/><meta name="twitter:image" content="https://reactnative.dev/img/logo-og.png"/><link rel="shortcut icon" href="/img/favicon.ico"/><link rel="stylesheet" href="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.css"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/solarized-dark.min.css"/><link rel="alternate" type="application/atom+xml" href="https://reactnative.dev/blog/atom.xml" title="React Native Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://reactnative.dev/blog/feed.xml" title="React Native Blog RSS Feed"/><script>
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</script></nav></div><div class="container mainContainer docsContainer"><div class="wrapper"><div class="post"><header class="postHeader"><a class="edit-page-link button" href="https://github.com/facebook/react-native-website/blob/master/docs/headless-js-android.md" target="_blank" rel="noreferrer noopener">Edit</a><h1 id="__docusaurus" class="postHeaderTitle">Headless JS</h1></header><article><div><span><p>Headless JS is a way to run tasks in JavaScript while your app is in the background. It can be used, for example, to sync fresh data, handle push notifications, or play music.</p>
<h2><a class="anchor" aria-hidden="true" id="the-js-api"></a><a href="#the-js-api" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>The JS API</h2>
<p>A task is an async function that you register on <code>AppRegistry</code>, similar to registering React applications:</p>
<pre><code class="hljs css language-jsx">AppRegistry<span class="token punctuation">.</span><span class="token function">registerHeadlessTask</span><span class="token punctuation">(</span><span class="token string">'SomeTaskName'</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=></span>
<span class="token function">require</span><span class="token punctuation">(</span><span class="token string">'SomeTaskName'</span><span class="token punctuation">)</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre>
<p>Then, in <code>SomeTaskName.js</code>:</p>
<pre><code class="hljs css language-jsx">module<span class="token punctuation">.</span><span class="token function-variable function">exports</span> <span class="token operator">=</span> <span class="token keyword">async</span> <span class="token punctuation">(</span><span class="token parameter">taskData</span><span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
<span class="token comment">// do stuff</span>
<span class="token punctuation">}</span><span class="token punctuation">;</span>
</code></pre>
<p>You can do anything in your task such as network requests, timers and so on, as long as it doesn't touch UI. Once your task completes (i.e. the promise is resolved), React Native will go into &quot;paused&quot; mode (unless there are other tasks running, or there is a foreground app).</p>
<h2><a class="anchor" aria-hidden="true" id="the-java-api"></a><a href="#the-java-api" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>The Java API</h2>
<p>Yes, this does still require some native code, but it's pretty thin. You need to extend <code>HeadlessJsTaskService</code> and override <code>getTaskConfig</code>, e.g.:</p>
<pre><code class="hljs css language-java"><span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">MyTaskService</span> <span class="token keyword">extends</span> <span class="token class-name">HeadlessJsTaskService</span> <span class="token punctuation">{</span>
<span class="token annotation punctuation">@Override</span>
<span class="token keyword">protected</span> <span class="token annotation punctuation">@Nullable</span> <span class="token class-name">HeadlessJsTaskConfig</span> <span class="token function">getTaskConfig</span><span class="token punctuation">(</span><span class="token class-name">Intent</span> intent<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token class-name">Bundle</span> extras <span class="token operator">=</span> intent<span class="token punctuation">.</span><span class="token function">getExtras</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>extras <span class="token operator">!=</span> <span class="token keyword">null</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token keyword">new</span> <span class="token class-name">HeadlessJsTaskConfig</span><span class="token punctuation">(</span>
<span class="token string">"SomeTaskName"</span><span class="token punctuation">,</span>
<span class="token class-name">Arguments</span><span class="token punctuation">.</span><span class="token function">fromBundle</span><span class="token punctuation">(</span>extras<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token number">5000</span><span class="token punctuation">,</span> <span class="token comment">// timeout for the task</span>
<span class="token boolean">false</span> <span class="token comment">// optional: defines whether or not the task is allowed in foreground. Default is false</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> <span class="token keyword">null</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>
<p>Then add the service to your <code>AndroidManifest.xml</code> file:</p>
<pre><code class="hljs">&lt;service android:<span class="hljs-built_in">name</span>=<span class="hljs-string">"com.example.MyTaskService"</span> /&gt;
</code></pre>
<p>Now, whenever you <a href="https://developer.android.com/reference/android/content/Context.html#startService(android.content.Intent)">start your service</a>, e.g. as a periodic task or in response to some system event / broadcast, JS will spin up, run your task, then spin down.</p>
<p>Example:</p>
<pre><code class="hljs css language-java"><span class="token class-name">Intent</span> service <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Intent</span><span class="token punctuation">(</span><span class="token function">getApplicationContext</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token class-name">MyTaskService</span><span class="token punctuation">.</span><span class="token keyword">class</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">Bundle</span> bundle <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Bundle</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
bundle<span class="token punctuation">.</span><span class="token function">putString</span><span class="token punctuation">(</span><span class="token string">"foo"</span><span class="token punctuation">,</span> <span class="token string">"bar"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
service<span class="token punctuation">.</span><span class="token function">putExtras</span><span class="token punctuation">(</span>bundle<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token function">getApplicationContext</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">startService</span><span class="token punctuation">(</span>service<span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="retries"></a><a href="#retries" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Retries</h2>
<p>By default, the headless JS task will not perform any retries. In order to do so, you need to create a <code>HeadlessJsRetryPolicy</code> and throw a specfic <code>Error</code>.</p>
<p><code>LinearCountingRetryPolicy</code> is an implementation of <code>HeadlessJsRetryPolicy</code> that allows you to specify a maximum number of retries with a fixed delay between each attempt. If that does not suit your needs then you can implement your own <code>HeadlessJsRetryPolicy</code>. These policies can be passed as an extra argument to the <code>HeadlessJsTaskConfig</code> constructor, e.g.</p>
<pre><code class="hljs css language-java"><span class="token class-name">HeadlessJsRetryPolicy</span> retryPolicy <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">LinearCountingRetryPolicy</span><span class="token punctuation">(</span>
<span class="token number">3</span><span class="token punctuation">,</span> <span class="token comment">// Max number of retry attempts</span>
<span class="token number">1000</span> <span class="token comment">// Delay between each retry attempt</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">return</span> <span class="token keyword">new</span> <span class="token class-name">HeadlessJsTaskConfig</span><span class="token punctuation">(</span>
<span class="token string">'SomeTaskName'</span><span class="token punctuation">,</span>
<span class="token class-name">Arguments</span><span class="token punctuation">.</span><span class="token function">fromBundle</span><span class="token punctuation">(</span>extras<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token number">5000</span><span class="token punctuation">,</span>
<span class="token boolean">false</span><span class="token punctuation">,</span>
retryPolicy
<span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre>
<p>A retry attempt will only be made when a specific <code>Error</code> is thrown. Inside a headless JS task, you can import the error and throw it when a retry attempt is required.</p>
<p>Example:</p>
<pre><code class="hljs css language-jsx"><span class="token keyword">import</span> <span class="token punctuation">{</span>HeadlessJsTaskError<span class="token punctuation">}</span> <span class="token keyword">from</span> <span class="token string">'HeadlessJsTask'</span><span class="token punctuation">;</span>
module<span class="token punctuation">.</span><span class="token function-variable function">exports</span> <span class="token operator">=</span> <span class="token keyword">async</span> <span class="token punctuation">(</span><span class="token parameter">taskData</span><span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
<span class="token keyword">const</span> condition <span class="token operator">=</span> <span class="token operator">...</span><span class="token punctuation">;</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>condition<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">throw</span> <span class="token keyword">new</span> <span class="token class-name">HeadlessJsTaskError</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 punctuation">;</span>
</code></pre>
<p>If you wish all errors to cause a retry attempt, you will need to catch them and throw the above error.</p>
<h2><a class="anchor" aria-hidden="true" id="caveats"></a><a href="#caveats" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Caveats</h2>
<ul>
<li>The function passed to <code>setTimeout</code> does not always behave as expected. Instead the function is called only when the application is launched again. If you only need to wait, use the retry functionality.</li>
<li>By default, your app will crash if you try to run a task while the app is in the foreground. This is to prevent developers from shooting themselves in the foot by doing a lot of work in a task and slowing the UI. You can pass a fourth <code>boolean</code> argument to control this behaviour.</li>
<li>If you start your service from a <code>BroadcastReceiver</code>, make sure to call <code>HeadlessJsTaskService.acquireWakeLockNow()</code> before returning from <code>onReceive()</code>.</li>
</ul>
<h2><a class="anchor" aria-hidden="true" id="example-usage"></a><a href="#example-usage" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Example Usage</h2>
<p>Service can be started from Java API. First you need to decide when the service should be started and implement your solution accordingly. Here is an example that reacts to network connection change.</p>
<p>Following lines shows part of Android manifest file for registering broadcast receiver.</p>
<pre><code class="hljs css language-xml"><span class="hljs-tag">&lt;<span class="hljs-name">receiver</span> <span class="hljs-attr">android:name</span>=<span class="hljs-string">".NetworkChangeReceiver"</span> &gt;</span>
<span class="hljs-tag">&lt;<span class="hljs-name">intent-filter</span>&gt;</span>
<span class="hljs-tag">&lt;<span class="hljs-name">action</span> <span class="hljs-attr">android:name</span>=<span class="hljs-string">"android.net.conn.CONNECTIVITY_CHANGE"</span> /&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">intent-filter</span>&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">receiver</span>&gt;</span>
</code></pre>
<p>Broadcast receiver then handles intent that was broadcasted in onReceive function. This is a great place to check whether your app is on foreground or not. If app is not on foreground we can prepare our intent to be started, with no information or additional information bundled using <code>putExtra</code> (keep in mind bundle can handle only parcelable values). In the end service is started and wakelock is acquired.</p>
<pre><code class="hljs css language-java"><span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">NetworkChangeReceiver</span> <span class="token keyword">extends</span> <span class="token class-name">BroadcastReceiver</span> <span class="token punctuation">{</span>
<span class="token annotation punctuation">@Override</span>
<span class="token keyword">public</span> <span class="token keyword">void</span> <span class="token function">onReceive</span><span class="token punctuation">(</span><span class="token keyword">final</span> <span class="token class-name">Context</span> context<span class="token punctuation">,</span> <span class="token keyword">final</span> <span class="token class-name">Intent</span> intent<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token comment">/**
This part will be called everytime network connection is changed
e.g. Connected -> Not Connected
**/</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span><span class="token function">isAppOnForeground</span><span class="token punctuation">(</span><span class="token punctuation">(</span>context<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token comment">/**
We will start our service and send extra info about
network connections
**/</span>
<span class="token keyword">boolean</span> hasInternet <span class="token operator">=</span> <span class="token function">isNetworkAvailable</span><span class="token punctuation">(</span>context<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">Intent</span> serviceIntent <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Intent</span><span class="token punctuation">(</span>context<span class="token punctuation">,</span> <span class="token class-name">MyTaskService</span><span class="token punctuation">.</span><span class="token keyword">class</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
serviceIntent<span class="token punctuation">.</span><span class="token function">putExtra</span><span class="token punctuation">(</span><span class="token string">"hasInternet"</span><span class="token punctuation">,</span> hasInternet<span class="token punctuation">)</span><span class="token punctuation">;</span>
context<span class="token punctuation">.</span><span class="token function">startService</span><span class="token punctuation">(</span>serviceIntent<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">HeadlessJsTaskService</span><span class="token punctuation">.</span><span class="token function">acquireWakeLockNow</span><span class="token punctuation">(</span>context<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">private</span> <span class="token keyword">boolean</span> <span class="token function">isAppOnForeground</span><span class="token punctuation">(</span><span class="token class-name">Context</span> context<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token comment">/**
We need to check if app is in foreground otherwise the app will crash.
http://stackoverflow.com/questions/8489993/check-android-application-is-in-foreground-or-not
**/</span>
<span class="token class-name">ActivityManager</span> activityManager <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token class-name">ActivityManager</span><span class="token punctuation">)</span> context<span class="token punctuation">.</span><span class="token function">getSystemService</span><span class="token punctuation">(</span><span class="token class-name">Context</span><span class="token punctuation">.</span>ACTIVITY_SERVICE<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">List</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">ActivityManager</span><span class="token punctuation">.</span><span class="token class-name">RunningAppProcessInfo</span><span class="token punctuation">></span></span> appProcesses <span class="token operator">=</span>
activityManager<span class="token punctuation">.</span><span class="token function">getRunningAppProcesses</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>appProcesses <span class="token operator">==</span> <span class="token keyword">null</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">final</span> <span class="token class-name">String</span> packageName <span class="token operator">=</span> context<span class="token punctuation">.</span><span class="token function">getPackageName</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token class-name">ActivityManager</span><span class="token punctuation">.</span><span class="token class-name">RunningAppProcessInfo</span> appProcess <span class="token operator">:</span> appProcesses<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>appProcess<span class="token punctuation">.</span>importance <span class="token operator">==</span>
<span class="token class-name">ActivityManager</span><span class="token punctuation">.</span><span class="token class-name">RunningAppProcessInfo</span><span class="token punctuation">.</span>IMPORTANCE_FOREGROUND <span class="token operator">&amp;&amp;</span>
appProcess<span class="token punctuation">.</span>processName<span class="token punctuation">.</span><span class="token function">equals</span><span class="token punctuation">(</span>packageName<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">boolean</span> <span class="token function">isNetworkAvailable</span><span class="token punctuation">(</span><span class="token class-name">Context</span> context<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token class-name">ConnectivityManager</span> cm <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token class-name">ConnectivityManager</span><span class="token punctuation">)</span>
context<span class="token punctuation">.</span><span class="token function">getSystemService</span><span class="token punctuation">(</span><span class="token class-name">Context</span><span class="token punctuation">.</span>CONNECTIVITY_SERVICE<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">NetworkInfo</span> netInfo <span class="token operator">=</span> cm<span class="token punctuation">.</span><span class="token function">getActiveNetworkInfo</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">return</span> <span class="token punctuation">(</span>netInfo <span class="token operator">!=</span> <span class="token keyword">null</span> <span class="token operator">&amp;&amp;</span> netInfo<span class="token punctuation">.</span><span class="token function">isConnected</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 punctuation">}</span>
</code></pre>
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