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<html><head><meta charset="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge, chrome=1"/><title>AccessibilityInfo · React Native</title><meta name="viewport" content="width=device-width"/><meta name="generator" content="Docusaurus"/><meta property="og:title" content="AccessibilityInfo · React Native"/><meta property="og:type" content="website"/><meta property="og:url" content="https://facebook.github.io/react-native/index.html"/><meta property="og:description" content="Sometimes it&#x27;s useful to know whether or not the device has a screen reader that is currently active. The `AccessibilityInfo` API is designed for this purpose. You can use it to query the current state of the screen reader as well as to register to be notified when the state of the screen reader changes."/><link rel="shortcut icon" href="/react-native/img/favicon.png"/><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://facebook.github.io/blog/atom.xml" title="React Native Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://facebook.github.io/blog/feed.xml" title="React Native Blog RSS Feed"/><script type="text/javascript" src="https://snack.expo.io/embed.js"></script><script type="text/javascript" src="/react-native/js/codeblocks.js"></script><link rel="stylesheet" href="/react-native/css/main.css"/></head><body class="sideNavVisible"><div class="fixedHeaderContainer"><div class="headerWrapper wrapper"><header><a href="/react-native/"><img class="logo" src="/react-native/img/header_logo.png"/><h2 class="headerTitle">React Native</h2></a><a href="/react-native/versions.html"><h3>0.41</h3></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li><a href="/react-native/docs/0.41/getting-started.html" target="_self">Docs</a></li><li><a href="/react-native/en/help.html" target="_self">Community</a></li><li><a href="/react-native/blog" target="_self">Blog</a></li><li class="navSearchWrapper reactNavSearchWrapper"><input type="text" id="search_input_react" placeholder="Search"/></li><li><a href="https://github.com/facebook/react-native" target="_self">GitHub</a></li><li><a href="https://reactjs.org/" target="_self">React</a></li></ul></nav></div></header></div></div><div class="navPusher"><div class="docMainWrapper wrapper"><div class="container mainContainer"><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/accessibilityinfo.md" target="_blank">Edit</a><h1>AccessibilityInfo</h1></header><article><div><span><p>Sometimes it's useful to know whether or not the device has a screen reader that is currently active. The <code>AccessibilityInfo</code> API is designed for this purpose. You can use it to query the current state of the screen reader as well as to register to be notified when the state of the screen reader changes.</p>
<p>Here's a small example illustrating how to use <code>AccessibilityInfo</code>:</p>
<pre><code class="hljs css javascript"><span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">ScreenReaderStatusExample</span> <span class="hljs-keyword">extends</span> <span class="hljs-title">React</span>.<span class="hljs-title">Component</span> </span>{
state = {
<span class="hljs-attr">screenReaderEnabled</span>: <span class="hljs-literal">false</span>,
};
componentDidMount() {
AccessibilityInfo.addEventListener(
<span class="hljs-string">'change'</span>,
<span class="hljs-keyword">this</span>._handleScreenReaderToggled
);
AccessibilityInfo.fetch().done(<span class="hljs-function">(<span class="hljs-params">isEnabled</span>) =&gt;</span> {
<span class="hljs-keyword">this</span>.setState({
<span class="hljs-attr">screenReaderEnabled</span>: isEnabled,
});
});
}
componentWillUnmount() {
AccessibilityInfo.removeEventListener(
<span class="hljs-string">'change'</span>,
<span class="hljs-keyword">this</span>._handleScreenReaderToggled
);
}
_handleScreenReaderToggled = <span class="hljs-function">(<span class="hljs-params">isEnabled</span>) =&gt;</span> {
<span class="hljs-keyword">this</span>.setState({
<span class="hljs-attr">screenReaderEnabled</span>: isEnabled,
});
};
render() {
<span class="hljs-keyword">return</span> (
<span class="xml"><span class="hljs-tag">&lt;<span class="hljs-name">View</span>&gt;</span>
<span class="hljs-tag">&lt;<span class="hljs-name">Text</span>&gt;</span>
The screen reader is{' '}
{this.state.screenReaderEnabled ? 'enabled' : 'disabled'}.
<span class="hljs-tag">&lt;/<span class="hljs-name">Text</span>&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">View</span>&gt;</span></span>
);
}
}
</code></pre>
<h3><a class="anchor" aria-hidden="true" name="methods"></a><a href="#methods" aria-hidden="true" class="hash-link" ><svg 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>Methods</h3>
<ul>
<li><a href="/react-native/docs/0.41/accessibilityinfo.html#fetch"><code>fetch</code></a></li>
<li><a href="/react-native/docs/0.41/accessibilityinfo.html#addeventlistener"><code>addEventListener</code></a></li>
<li><a href="/react-native/docs/0.41/accessibilityinfo.html#setaccessibilityfocus"><code>setAccessibilityFocus</code></a></li>
<li><a href="/react-native/docs/0.41/accessibilityinfo.html#announceforaccessibility"><code>announceForAccessibility</code></a></li>
<li><a href="/react-native/docs/0.41/accessibilityinfo.html#removeeventlistener"><code>removeEventListener</code></a></li>
</ul>
<hr>
<h1><a class="anchor" aria-hidden="true" name="reference"></a><a href="#reference" aria-hidden="true" class="hash-link" ><svg 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>Reference</h1>
<h2><a class="anchor" aria-hidden="true" name="methods"></a><a href="#methods" aria-hidden="true" class="hash-link" ><svg 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>Methods</h2>
<h3><a class="anchor" aria-hidden="true" name="fetch"></a><a href="#fetch" aria-hidden="true" class="hash-link" ><svg 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><code>fetch()</code></h3>
<pre><code class="hljs css javascript">AccessibilityInfo.fetch();
</code></pre>
<p>Query whether a screen reader is currently enabled. Returns a promise which resolves to a boolean. The result is <code>true</code> when a screen reader is enabled and <code>false</code> otherwise.</p>
<hr>
<h3><a class="anchor" aria-hidden="true" name="addeventlistener"></a><a href="#addeventlistener" aria-hidden="true" class="hash-link" ><svg 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><code>addEventListener()</code></h3>
<pre><code class="hljs css javascript">AccessibilityInfo.addEventListener(eventName, handler);
</code></pre>
<p>Add an event handler.</p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>eventName</td><td>string</td><td>Yes</td><td>Name of the event</td></tr>
<tr><td>handler</td><td>function</td><td>Yes</td><td>Event handler</td></tr>
</tbody>
</table>
<p>Supported events:</p>
<ul>
<li><code>change</code>: Fires when the state of the screen reader changes. The argument to the event handler is a boolean. The boolean is <code>true</code> when a screen reader is enabled and <code>false</code> otherwise.</li>
<li><code>announcementFinished</code>: iOS-only event. Fires when the screen reader has finished making an announcement. The argument to the event handler is a dictionary with these keys:
<ul>
<li><code>announcement</code>: The string announced by the screen reader.</li>
<li><code>success</code>: A boolean indicating whether the announcement was successfully made.</li>
</ul></li>
</ul>
<hr>
<h3><a class="anchor" aria-hidden="true" name="setaccessibilityfocus"></a><a href="#setaccessibilityfocus" aria-hidden="true" class="hash-link" ><svg 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><code>setAccessibilityFocus()</code></h3>
<pre><code class="hljs css javascript">AccessibilityInfo.setAccessibilityFocus(reactTag);
</code></pre>
<p>Set accessibility focus to a React component.</p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>reactTag</td><td>number</td><td>Yes</td><td>React component tag</td></tr>
</tbody>
</table>
<table>
<thead>
<tr><th>Platform</th></tr>
</thead>
<tbody>
<tr><td>iOS</td></tr>
</tbody>
</table>
<hr>
<h3><a class="anchor" aria-hidden="true" name="announceforaccessibility"></a><a href="#announceforaccessibility" aria-hidden="true" class="hash-link" ><svg 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><code>announceForAccessibility()</code></h3>
<pre><code class="hljs css javascript">AccessibilityInfo.announceForAccessibility(announcement);
</code></pre>
<p>Post a string to be announced by the screen reader.</p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>announcement</td><td>string</td><td>Yes</td><td>String to be announced</td></tr>
</tbody>
</table>
<table>
<thead>
<tr><th>Platform</th></tr>
</thead>
<tbody>
<tr><td>iOS</td></tr>
</tbody>
</table>
<hr>
<h3><a class="anchor" aria-hidden="true" name="removeeventlistener"></a><a href="#removeeventlistener" aria-hidden="true" class="hash-link" ><svg 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><code>removeEventListener()</code></h3>
<pre><code class="hljs css javascript">AccessibilityInfo.removeEventListener(eventName, handler);
</code></pre>
<p>Remove an event handler.</p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>eventName</td><td>string</td><td>Yes</td><td>Name of the event</td></tr>
<tr><td>handler</td><td>function</td><td>Yes</td><td>Event handler</td></tr>
</tbody>
</table>
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