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<script src="https://snack.expo.io/embed.js" defer="defer"></script><title data-react-helmet="true">BackHandler · React Native</title><meta data-react-helmet="true" property="twitter:image" content="https://reactnative.dev/img/logo-og.png"><meta data-react-helmet="true" name="twitter:image:alt" content="Image for React Native"><meta data-react-helmet="true" name="docsearch:language" content="en"><meta data-react-helmet="true" name="docsearch:version" content="0.63"><meta data-react-helmet="true" name="docsearch:docusaurus_tag" content="docs-default-0.63"><meta data-react-helmet="true" property="og:image" content="https://reactnative.dev/img/logo-og.png"><meta data-react-helmet="true" name="twitter:card" content="summary"><meta data-react-helmet="true" name="twitter:image" content="https://reactnative.dev/img/logo-og.png"><meta data-react-helmet="true" property="og:title" content="BackHandler · React Native"><meta data-react-helmet="true" name="description" content="The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system&#x27;s back action, and lets you control how your application responds. It is Android-only."><meta data-react-helmet="true" property="og:description" content="The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system&#x27;s back action, and lets you control how your application responds. It is Android-only."><meta data-react-helmet="true" property="og:url" content="https://reactnative.dev/docs/backhandler"><link data-react-helmet="true" rel="shortcut icon" href="/img/favicon.ico"><link data-react-helmet="true" rel="preconnect" href="https://BH4D9OD16A-dsn.algolia.net" crossorigin="anonymous"><link data-react-helmet="true" rel="canonical" href="https://reactnative.dev/docs/backhandler"><link rel="stylesheet" href="/styles.fccefeba.css">
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href="/docs/vibration">Vibration</a></li><li class="menu__list-item"><a class="menu__link menu__link--sublist" href="#!" tabindex="0">Hooks</a><ul class="menu__list"><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/usecolorscheme">useColorScheme</a></li><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/usewindowdimensions">useWindowDimensions</a></li></ul></li><li class="menu__list-item"><a class="menu__link menu__link--sublist menu__link--active" href="#!" tabindex="0">Android APIs</a><ul class="menu__list"><li class="menu__list-item"><a aria-current="page" class="menu__link menu__link--active active" tabindex="0" href="/docs/backhandler">BackHandler</a></li><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/permissionsandroid">PermissionsAndroid</a></li><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/toastandroid">ToastAndroid</a></li></ul></li><li class="menu__list-item"><a class="menu__link menu__link--sublist" href="#!" tabindex="0">iOS APIs</a><ul class="menu__list"><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/actionsheetios">ActionSheetIOS</a></li><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/dynamiccolorios">DynamicColorIOS</a></li><li class="menu__list-item"><a class="menu__link" tabindex="0" href="/docs/settings">Settings</a></li></ul></li></ul></li></ul></div></div></div><main class="docMainContainer_1rYT"><div class="container padding-vert--lg docItemWrapper_1Hme"><div class="row"><div class="col docItemCol_2AGf"><div class="docItemContainer_1tAC"><article><header><h1 class="docTitle_cWlf">BackHandler</h1></header><div class="markdown"><p>The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system&#x27;s back action, and lets you control how your application responds. It is Android-only.</p><p>The event subscriptions are called in reverse order (i.e. the last registered subscription is called first).</p><ul><li><strong>If one subscription returns true,</strong> then subscriptions registered earlier will not be called.</li><li><strong>If no subscription returns true or none are registered,</strong> it programmatically invokes the default back button functionality to exit the app.</li></ul><blockquote><p><strong>Warning for modal users:</strong> If your app shows an opened <code>Modal</code>, <code>BackHandler</code> will not publish any events (<a href="/docs/modal#onrequestclose">see <code>Modal</code> docs</a>).</p></blockquote><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="pattern"></a>Pattern<a aria-hidden="true" tabindex="-1" class="hash-link" href="#pattern" title="Direct link to heading">#</a></h2><div class="mdxCodeBlock_xYIz"><div class="codeBlockContent_rlEb"><button tabindex="0" type="button" aria-label="Copy code to clipboard" class="copyButton_kOW4">Copy</button><div class="prism-code language-jsx codeBlock_1AP7"><div class="codeBlockLines_1boI" style="color:#FFFFFF;background:#282C34"><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain">BackHandler</span><span class="token punctuation" style="color:#657b83">.</span><span class="token function" style="color:#79b6f2">addEventListener</span><span class="token punctuation" style="color:#657b83">(</span><span class="token string" style="color:#8dc891">&#x27;hardwareBackPress&#x27;</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">function</span><span class="token punctuation" style="color:#657b83">(</span><span class="token punctuation" style="color:#657b83">)</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">{</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token comment" style="color:#93a1a1">/**</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * this.onMainScreen and this.goBack are just examples,</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * you need to use your own implementation here.</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> *</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * Typically you would use the navigator here to go to the last state.</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> */</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">(</span><span class="token operator" style="color:#fc929e">!</span><span class="token keyword" style="color:#c5a5c5">this</span><span class="token punctuation" style="color:#657b83">.</span><span class="token function" style="color:#79b6f2">onMainScreen</span><span class="token punctuation" style="color:#657b83">(</span><span class="token punctuation" style="color:#657b83">)</span><span class="token punctuation" style="color:#657b83">)</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">{</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">this</span><span class="token punctuation" style="color:#657b83">.</span><span class="token function" style="color:#79b6f2">goBack</span><span class="token punctuation" style="color:#657b83">(</span><span class="token punctuation" style="color:#657b83">)</span><span class="token punctuation" style="color:#657b83">;</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token comment" style="color:#93a1a1">/**</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * When true is returned the event will not be bubbled up</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * &amp; no other back action will execute</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> */</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">return</span><span class="token plain"> </span><span class="token boolean" style="color:#ff8b50">true</span><span class="token punctuation" style="color:#657b83">;</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">}</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token comment" style="color:#93a1a1">/**</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * Returning false will let the event to bubble up &amp; let other event listeners</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> * or the system&#x27;s default back action to be executed.</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token comment" style="color:#93a1a1"> */</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">return</span><span class="token plain"> </span><span class="token boolean" style="color:#ff8b50">false</span><span class="token punctuation" style="color:#657b83">;</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token punctuation" style="color:#657b83">}</span><span class="token punctuation" style="color:#657b83">)</span><span class="token punctuation" style="color:#657b83">;</span></div></div></div></div></div><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="example"></a>Example<a aria-hidden="true" tabindex="-1" class="hash-link" href="#example" title="Direct link to heading">#</a></h2><p>The following example implements a scenario where you confirm if the user wants to exit the app:</p><div><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_3gSF tabs__item--active" style="outline:none">Function Component</li><li role="tab" tabindex="0" aria-selected="false" class="tabs__item tabItem_3gSF" style="outline:none">Class Component</li></ul><div role="tabpanel" class="margin-vert--md"><div><div class="snack-player" data-snack-name="BackHandler" data-snack-description="Example usage" data-snack-code="import%20React%2C%20%7B%20useEffect%20%7D%20from%20%22react%22%3B%0Aimport%20%7B%20Text%2C%20View%2C%20StyleSheet%2C%20BackHandler%2C%20Alert%20%7D%20from%20%22react-native%22%3B%0A%0Aconst%20App%20%3D%20()%20%3D%3E%20%7B%0A%20%20useEffect(()%20%3D%3E%20%7B%0A%20%20%20%20const%20backAction%20%3D%20()%20%3D%3E%20%7B%0A%20%20%20%20%20%20Alert.alert(%22Hold%20on!%22%2C%20%22Are%20you%20sure%20you%20want%20to%20go%20back%3F%22%2C%20%5B%0A%20%20%20%20%20%20%20%20%7B%0A%20%20%20%20%20%20%20%20%20%20text%3A%20%22Cancel%22%2C%0A%20%20%20%20%20%20%20%20%20%20onPress%3A%20()%20%3D%3E%20null%2C%0A%20%20%20%20%20%20%20%20%20%20style%3A%20%22cancel%22%0A%20%20%20%20%20%20%20%20%7D%2C%0A%20%20%20%20%20%20%20%20%7B%20text%3A%20%22YES%22%2C%20onPress%3A%20()%20%3D%3E%20BackHandler.exitApp()%20%7D%0A%20%20%20%20%20%20%5D)%3B%0A%20%20%20%20%20%20return%20true%3B%0A%20%20%20%20%7D%3B%0A%0A%20%20%20%20const%20backHandler%20%3D%20BackHandler.addEventListener(%0A%20%20%20%20%20%20%22hardwareBackPress%22%2C%0A%20%20%20%20%20%20backAction%0A%20%20%20%20)%3B%0A%0A%20%20%20%20return%20()%20%3D%3E%20backHandler.remove()%3B%0A%20%20%7D%2C%20%5B%5D)%3B%0A%0A%20%20return%20(%0A%20%20%20%20%3CView%20style%3D%7Bstyles.container%7D%3E%0A%20%20%20%20%20%20%3CText%20style%3D%7Bstyles.text%7D%3EClick%20Back%20button!%3C%2FText%3E%0A%20%20%20%20%3C%2FView%3E%0A%20%20)%3B%0A%7D%3B%0A%0Aconst%20styles%20%3D%20StyleSheet.create(%7B%0A%20%20container%3A%20%7B%0A%20%20%20%20flex%3A%201%2C%0A%20%20%20%20alignItems%3A%20%22center%22%2C%0A%20%20%20%20justifyContent%3A%20%22center%22%0A%20%20%7D%2C%0A%20%20text%3A%20%7B%0A%20%20%20%20fontSize%3A%2018%2C%0A%20%20%20%20fontWeight%3A%20%22bold%22%0A%20%20%7D%0A%7D)%3B%0A%0Aexport%20default%20App%3B" data-snack-platform="web" data-snack-supported-platforms="android" data-snack-theme="light" data-snack-preview="true"></div></div></div></div><p><code>BackHandler.addEventListener</code> creates an event listener &amp; returns a <code>NativeEventSubscription</code> object which should be cleared using <code>NativeEventSubscription.remove</code> method.</p><p>Additionally <code>BackHandler.removeEventListener</code> can also be used to clear the event listener. Ensure the callback has the reference to the same function used in the <code>addEventListener</code> call as shown the following example ﹣</p><div><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_3gSF tabs__item--active" style="outline:none">Function Component</li><li role="tab" tabindex="0" aria-selected="false" class="tabs__item tabItem_3gSF" style="outline:none">Class Component</li></ul><div role="tabpanel" class="margin-vert--md"><div><div class="snack-player" data-snack-name="BackHandler" data-snack-description="Example usage" data-snack-code="import%20React%2C%20%7B%20useEffect%20%7D%20from%20%22react%22%3B%0Aimport%20%7B%20Text%2C%20View%2C%20StyleSheet%2C%20BackHandler%2C%20Alert%20%7D%20from%20%22react-native%22%3B%0A%0Aconst%20App%20%3D%20()%20%3D%3E%20%7B%0A%20%20const%20backAction%20%3D%20()%20%3D%3E%20%7B%0A%20%20%20%20Alert.alert(%22Hold%20on!%22%2C%20%22Are%20you%20sure%20you%20want%20to%20go%20back%3F%22%2C%20%5B%0A%20%20%20%20%20%20%7B%0A%20%20%20%20%20%20%20%20text%3A%20%22Cancel%22%2C%0A%20%20%20%20%20%20%20%20onPress%3A%20()%20%3D%3E%20null%2C%0A%20%20%20%20%20%20%20%20style%3A%20%22cancel%22%0A%20%20%20%20%20%20%7D%2C%0A%20%20%20%20%20%20%7B%20text%3A%20%22YES%22%2C%20onPress%3A%20()%20%3D%3E%20BackHandler.exitApp()%20%7D%0A%20%20%20%20%5D)%3B%0A%20%20%20%20return%20true%3B%0A%20%20%7D%3B%0A%0A%20%20useEffect(()%20%3D%3E%20%7B%0A%20%20%20%20BackHandler.addEventListener(%22hardwareBackPress%22%2C%20backAction)%3B%0A%0A%20%20%20%20return%20()%20%3D%3E%0A%20%20%20%20%20%20BackHandler.removeEventListener(%22hardwareBackPress%22%2C%20backAction)%3B%0A%20%20%7D%2C%20%5B%5D)%3B%0A%0A%20%20return%20(%0A%20%20%20%20%3CView%20style%3D%7Bstyles.container%7D%3E%0A%20%20%20%20%20%20%3CText%20style%3D%7Bstyles.text%7D%3EClick%20Back%20button!%3C%2FText%3E%0A%20%20%20%20%3C%2FView%3E%0A%20%20)%3B%0A%7D%3B%0A%0Aconst%20styles%20%3D%20StyleSheet.create(%7B%0A%20%20container%3A%20%7B%0A%20%20%20%20flex%3A%201%2C%0A%20%20%20%20alignItems%3A%20%22center%22%2C%0A%20%20%20%20justifyContent%3A%20%22center%22%0A%20%20%7D%2C%0A%20%20text%3A%20%7B%0A%20%20%20%20fontSize%3A%2018%2C%0A%20%20%20%20fontWeight%3A%20%22bold%22%0A%20%20%7D%0A%7D)%3B%0A%0Aexport%20default%20App%3B" data-snack-platform="web" data-snack-supported-platforms="android" data-snack-theme="light" data-snack-preview="true"></div></div></div></div><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="usage-with-react-navigation"></a>Usage with React Navigation<a aria-hidden="true" tabindex="-1" class="hash-link" href="#usage-with-react-navigation" title="Direct link to heading">#</a></h2><p>If you are using React Navigation to navigate across different screens, you can follow their guide on <a href="https://reactnavigation.org/docs/custom-android-back-button-handling/" target="_blank" rel="noopener noreferrer">Custom Android back button behaviour</a></p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="backhandler-hook"></a>Backhandler hook<a aria-hidden="true" tabindex="-1" class="hash-link" href="#backhandler-hook" title="Direct link to heading">#</a></h2><p><a href="https://github.com/react-native-community/hooks#usebackhandler" target="_blank" rel="noopener noreferrer">React Native Hooks</a> has a nice <code>useBackHandler</code> hook which will simplify the process of setting up event listeners.</p><hr><h1><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="reference"></a>Reference<a aria-hidden="true" tabindex="-1" class="hash-link" href="#reference" title="Direct link to heading">#</a></h1><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="methods"></a>Methods<a aria-hidden="true" tabindex="-1" class="hash-link" href="#methods" title="Direct link to heading">#</a></h2><h3><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="addeventlistener"></a><code>addEventListener()</code><a aria-hidden="true" tabindex="-1" class="hash-link" href="#addeventlistener" title="Direct link to heading">#</a></h3><div class="mdxCodeBlock_xYIz"><div class="codeBlockContent_rlEb"><button tabindex="0" type="button" aria-label="Copy code to clipboard" class="copyButton_kOW4">Copy</button><div class="prism-code language-jsx codeBlock_1AP7"><div class="codeBlockLines_1boI" style="color:#FFFFFF;background:#282C34"><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token keyword" style="color:#c5a5c5">static</span><span class="token plain"> </span><span class="token function" style="color:#79b6f2">addEventListener</span><span class="token punctuation" style="color:#657b83">(</span><span class="token plain">eventName</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> handler</span><span class="token punctuation" style="color:#657b83">)</span></div></div></div></div></div><hr><h3><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="exitapp"></a><code>exitApp()</code><a aria-hidden="true" tabindex="-1" class="hash-link" href="#exitapp" title="Direct link to heading">#</a></h3><div class="mdxCodeBlock_xYIz"><div class="codeBlockContent_rlEb"><button tabindex="0" type="button" aria-label="Copy code to clipboard" class="copyButton_kOW4">Copy</button><div class="prism-code language-jsx codeBlock_1AP7"><div class="codeBlockLines_1boI" style="color:#FFFFFF;background:#282C34"><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token keyword" style="color:#c5a5c5">static</span><span class="token plain"> </span><span class="token function" style="color:#79b6f2">exitApp</span><span class="token punctuation" style="color:#657b83">(</span><span class="token punctuation" style="color:#657b83">)</span></div></div></div></div></div><hr><h3><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="removeeventlistener"></a><code>removeEventListener()</code><a aria-hidden="true" tabindex="-1" class="hash-link" href="#removeeventlistener" title="Direct link to heading">#</a></h3><div class="mdxCodeBlock_xYIz"><div class="codeBlockContent_rlEb"><button tabindex="0" type="button" aria-label="Copy code to clipboard" class="copyButton_kOW4">Copy</button><div class="prism-code language-jsx codeBlock_1AP7"><div class="codeBlockLines_1boI" style="color:#FFFFFF;background:#282C34"><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token keyword" style="color:#c5a5c5">static</span><span class="token plain"> </span><span class="token function" style="color:#79b6f2">removeEventListener</span><span class="token punctuation" style="color:#657b83">(</span><span class="token plain">eventName</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> handler</span><span class="token punctuation" style="color:#657b83">)</span></div></div></div></div></div></div></article><div class="docMetadata margin-vert--xl"><div class="row"><div class="col"><a href="https://github.com/facebook/react-native-website/blob/master/website/versioned_docs/version-0.63/backhandler.md" target="_blank" rel="noreferrer noopener"><svg fill="currentColor" height="1.2em" width="1.2em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 40 40" style="margin-right:0.3em;vertical-align:sub"><g><path d="m34.5 11.7l-3 3.1-6.3-6.3 3.1-3q0.5-0.5 1.2-0.5t1.1 0.5l3.9 3.9q0.5 0.4 0.5 1.1t-0.5 1.2z m-29.5 17.1l18.4-18.5 6.3 6.3-18.4 18.4h-6.3v-6.2z"></path></g></svg>Edit this page</a></div><div class="col text--right"><em><small class="docMetadata-updated">Last updated on <time datetime="2020-10-29T04:19:29.000Z" class="docLastUpdatedAt_1gIo">10/29/2020</time></small></em></div></div></div><div class="margin-vert--lg"><nav class="pagination-nav" aria-label="Blog list page navigation"><div class="pagination-nav__item"><a class="pagination-nav__link" href="/docs/usewindowdimensions"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">« useWindowDimensions</div></a></div><div class="pagination-nav__item pagination-nav__item--next"><a class="pagination-nav__link" href="/docs/permissionsandroid"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">PermissionsAndroid »</div></a></div></nav></div></div></div><div class="col col--3"><div class="tableOfContents_3iuQ"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#pattern" class="table-of-contents__link">Pattern</a></li><li><a href="#example" class="table-of-contents__link">Example</a></li><li><a href="#usage-with-react-navigation" class="table-of-contents__link">Usage with React Navigation</a></li><li><a href="#backhandler-hook" class="table-of-contents__link">Backhandler hook</a></li><li><a href="#methods" class="table-of-contents__link">Methods</a><ul><li><a href="#addeventlistener" class="table-of-contents__link"><code>addEventListener()</code></a></li><li><a href="#exitapp" class="table-of-contents__link"><code>exitApp()</code></a></li><li><a href="#removeeventlistener" 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