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1<!doctype html><html lang=en dir=ltr class="docs-wrapper plugin-docs plugin-id-default docs-version-0.79 docs-doc-page docs-doc-id-backhandler" data-has-hydrated=false><meta charset=UTF-8><meta name=generator content="Docusaurus v3.8.0"><title data-rh=true>BackHandler · React Native</title><meta data-rh=true name=viewport content="width=device-width, initial-scale=1.0"><meta data-rh=true property=og:url content=https://reactnative.dev/docs/backhandler><meta data-rh=true property=og:locale content=en><meta data-rh=true name=docusaurus_locale content=en><meta data-rh=true name=docsearch:language content=en><meta data-rh=true property=og:image content=https://reactnative.dev/img/logo-share.png><meta data-rh=true name=twitter:card content=summary_large_image><meta data-rh=true name=twitter:image content=https://reactnative.dev/img/logo-share.png><meta data-rh=true name=twitter:site content=@reactnative><meta data-rh=true name=docusaurus_version content=0.79><meta data-rh=true name=docusaurus_tag content=docs-default-0.79><meta data-rh=true name=docsearch:version content=0.79><meta data-rh=true name=docsearch:docusaurus_tag content=docs-default-0.79><meta data-rh=true property=og:title content="BackHandler · React Native"><meta data-rh=true name=description content="The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system's back action, and lets you control how your application responds. It is Android-only."><meta data-rh=true property=og:description content="The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system's back action, and lets you control how your application responds. 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markdown"><header><h1>BackHandler</h1></header><p>The Backhandler API detects hardware button presses for back navigation, lets you register event listeners for the system's back action, and lets you control how your application responds. It is Android-only.</p> 5<p>The event subscriptions are called in reverse order (i.e. the last registered subscription is called first).</p> 6<ul> 7<li><strong>If one subscription returns true,</strong> then subscriptions registered earlier will not be called.</li> 8<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> 9</ul> 10<blockquote> 11<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> 12</blockquote> 13<h2 class="anchor anchorWithStickyNavbar_JmGV" id=pattern>Pattern<a href=#pattern class=hash-link aria-label="Direct link to Pattern" title="Direct link to Pattern">​</a></h2> 14<div class="language-tsx codeBlockContainer_mQmQ theme-code-block" style=--prism-color:#FFFFFF;--prism-background-color:#282C34><div class=codeBlockTitle_kY6l>tsx</div><div class=codeBlockContent_t_Hd><pre tabindex=0 class="prism-code language-tsx codeBlock_RMoD thin-scrollbar" style=color:#FFFFFF;background-color:#282C34><code class=codeBlockLines_AclH><span class=token-line style=color:#FFFFFF><span class="token keyword" style=color:#c5a5c5>const</span><span class="token plain"> subscription </span><span class="token operator" style=color:#fc929e>=</span><span class="token plain"> </span><span class="token maybe-class-name">BackHandler</span><span class="token punctuation" style=color:#657b83>.</span><span class="token method function property-access" style=color:#79b6f2>addEventListener</span><span class="token punctuation" style=color:#657b83>(</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token string" style=color:#8dc891>'hardwareBackPress'</span><span class="token punctuation" style=color:#657b83>,</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token keyword" style=color:#c5a5c5>function</span><span class="token plain"> </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><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token comment" style=color:#93a1a1>/**</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * this.onMainScreen and this.goBack are just examples,</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * you need to use your own implementation here.</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> *</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * Typically you would use the navigator here to go to the last state.</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> */</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain" style=display:inline-block></span><br></span><span class=token-line style=color:#FFFFFF><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 method function property-access" 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><br></span><span class=token-line style=color:#FFFFFF><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 method function property-access" 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><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token comment" style=color:#93a1a1>/**</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * When true is returned the event will not be bubbled up</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * & no other back action will execute</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> */</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><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><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token punctuation" style=color:#657b83>}</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token comment" style=color:#93a1a1>/**</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * Returning false will let the event to bubble up & let other event listeners</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> * or the system's default back action to be executed.</span><br></span><span class=token-line style=color:#FFFFFF><span class="token comment" style=color:#93a1a1> */</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><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><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token punctuation" style=color:#657b83>}</span><span class="token punctuation" style=color:#657b83>,</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"></span><span class="token punctuation" style=color:#657b83>)</span><span class="token punctuation" style=color:#657b83>;</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain" style=display:inline-block></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"></span><span class="token comment" style=color:#93a1a1>// Unsubscribe the listener on unmount</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain">subscription</span><span class="token punctuation" style=color:#657b83>.</span><span class="token method function property-access" style=color:#79b6f2>remove</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><br></span></code></pre></div></div> 15<h2 class="anchor anchorWithStickyNavbar_JmGV" id=example>Example<a href=#example class=hash-link aria-label="Direct link to Example" title="Direct link to Example">​</a></h2> 16<p>The following example implements a scenario where you confirm if the user wants to exit the app:</p> 17<div class=snack-player data-snack-name=BackHandler data-snack-description="Example usage" data-snack-files="%7B%22App.tsx%22%3A%7B%22type%22%3A%22CODE%22%2C%22contents%22%3A%22import%20React%2C%20%7BuseEffect%7D%20from%20'react'%3B%5Cnimport%20%7BText%2C%20StyleSheet%2C%20BackHandler%2C%20Alert%7D%20from%20'react-native'%3B%5Cnimport%20%7BSafeAreaView%2C%20SafeAreaProvider%7D%20from%20'react-native-safe-area-context'%3B%5Cn%5Cnconst%20App%20%3D%20()%20%3D%3E%20%7B%5Cn%20%20useEffect(()%20%3D%3E%20%7B%5Cn%20%20%20%20const%20backAction%20%3D%20()%20%3D%3E%20%7B%5Cn%20%20%20%20%20%20Alert.alert('Hold%20on!'%2C%20'Are%20you%20sure%20you%20want%20to%20go%20back%3F'%2C%20%5B%5Cn%20%20%20%20%20%20%20%20%7B%5Cn%20%20%20%20%20%20%20%20%20%20text%3A%20'Cancel'%2C%5Cn%20%20%20%20%20%20%20%20%20%20onPress%3A%20()%20%3D%3E%20null%2C%5Cn%20%20%20%20%20%20%20%20%20%20style%3A%20'cancel'%2C%5Cn%20%20%20%20%20%20%20%20%7D%2C%5Cn%20%20%20%20%20%20%20%20%7Btext%3A%20'YES'%2C%20onPress%3A%20()%20%3D%3E%20BackHandler.exitApp()%7D%2C%5Cn%20%20%20%20%20%20%5D)%3B%5Cn%20%20%20%20%20%20return%20true%3B%5Cn%20%20%20%20%7D%3B%5Cn%5Cn%20%20%20%20const%20backHandler%20%3D%20BackHandler.addEventListener(%5Cn%20%20%20%20%20%20'hardwareBackPress'%2C%5Cn%20%20%20%20%20%20backAction%2C%5Cn%20%20%20%20)%3B%5Cn%5Cn%20%20%20%20return%20()%20%3D%3E%20backHandler.remove()%3B%5Cn%20%20%7D%2C%20%5B%5D)%3B%5Cn%5Cn%20%20return%20(%5Cn%20%20%20%20%3CSafeAreaProvider%3E%5Cn%20%20%20%20%20%20%3CSafeAreaView%20style%3D%7Bstyles.container%7D%3E%5Cn%20%20%20%20%20%20%20%20%3CText%20style%3D%7Bstyles.text%7D%3EClick%20Back%20button!%3C%2FText%3E%5Cn%20%20%20%20%20%20%3C%2FSafeAreaView%3E%5Cn%20%20%20%20%3C%2FSafeAreaProvider%3E%5Cn%20%20)%3B%5Cn%7D%3B%5Cn%5Cnconst%20styles%20%3D%20StyleSheet.create(%7B%5Cn%20%20container%3A%20%7B%5Cn%20%20%20%20flex%3A%201%2C%5Cn%20%20%20%20alignItems%3A%20'center'%2C%5Cn%20%20%20%20justifyContent%3A%20'center'%2C%5Cn%20%20%7D%2C%5Cn%20%20text%3A%20%7B%5Cn%20%20%20%20fontSize%3A%2018%2C%5Cn%20%20%20%20fontWeight%3A%20'bold'%2C%5Cn%20%20%7D%2C%5Cn%7D)%3B%5Cn%5Cnexport%20default%20App%3B%22%7D%7D" data-snack-dependencies=react-native-safe-area-context data-snack-platform=web data-snack-supported-platforms=android data-snack-theme=light data-snack-preview=true data-snack-loading=lazy data-snack-device-frame=false></div> 18<p><code>BackHandler.addEventListener</code> creates an event listener & returns a <code>NativeEventSubscription</code> object which should be cleared using <code>NativeEventSubscription.remove</code> method.</p> 19<h2 class="anchor anchorWithStickyNavbar_JmGV" id=usage-with-react-navigation>Usage with React Navigation<a href=#usage-with-react-navigation class=hash-link aria-label="Direct link to Usage with React Navigation" title="Direct link to Usage with React Navigation">​</a></h2> 20<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> 21<h2 class="anchor anchorWithStickyNavbar_JmGV" id=backhandler-hook>Backhandler hook<a href=#backhandler-hook class=hash-link aria-label="Direct link to Backhandler hook" title="Direct link to Backhandler hook">​</a></h2> 22<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> 23<hr> 24<h1>Reference</h1> 25<h2 class="anchor anchorWithStickyNavbar_JmGV" id=methods>Methods<a href=#methods class=hash-link aria-label="Direct link to Methods" title="Direct link to Methods">​</a></h2> 26<h3 class="anchor anchorWithStickyNavbar_JmGV" id=addeventlistener><code>addEventListener()</code><a href=#addeventlistener class=hash-link aria-label="Direct link to addeventlistener" title="Direct link to addeventlistener">​</a></h3> 27<div class="language-tsx codeBlockContainer_mQmQ theme-code-block" style=--prism-color:#FFFFFF;--prism-background-color:#282C34><div class=codeBlockTitle_kY6l>tsx</div><div class=codeBlockContent_t_Hd><pre tabindex=0 class="prism-code language-tsx codeBlock_RMoD thin-scrollbar" style=color:#FFFFFF;background-color:#282C34><code class=codeBlockLines_AclH><span class=token-line style=color:#FFFFFF><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"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> eventName</span><span class="token operator" style=color:#fc929e>:</span><span class="token plain"> </span><span class="token maybe-class-name">BackPressEventName</span><span class="token punctuation" style=color:#657b83>,</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"> </span><span class="token function-variable function" style=color:#79b6f2>handler</span><span class="token operator" style=color:#fc929e>:</span><span class="token plain"> </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 arrow operator" style=color:#fc929e>=></span><span class="token plain"> </span><span class="token builtin" style=color:#2aa198>boolean</span><span class="token plain"> </span><span class="token operator" style=color:#fc929e>|</span><span class="token plain"> </span><span class="token keyword" style=color:#c5a5c5>null</span><span class="token plain"> </span><span class="token operator" style=color:#fc929e>|</span><span class="token plain"> </span><span class="token keyword" style=color:#c5a5c5>undefined</span><span class="token punctuation" style=color:#657b83>,</span><span class="token plain"></span><br></span><span class=token-line style=color:#FFFFFF><span class="token plain"></span><span class="token punctuation" style=color:#657b83>)</span><span class="token operator" style=color:#fc929e>:</span><span class="token plain"> </span><span class="token maybe-class-name">NativeEventSubscription</span><span class="token punctuation" style=color:#657b83>;</span><br></span></code></pre></div></div> 28<hr> 29<h3 class="anchor anchorWithStickyNavbar_JmGV" id=exitapp><code>exitApp()</code><a href=#exitapp class=hash-link aria-label="Direct link to exitapp" title="Direct link to exitapp">​</a></h3> 30<div class="language-tsx codeBlockContainer_mQmQ theme-code-block" style=--prism-color:#FFFFFF;--prism-background-color:#282C34><div class=codeBlockTitle_kY6l>tsx</div><div class=codeBlockContent_t_Hd><pre tabindex=0 class="prism-code language-tsx codeBlock_RMoD thin-scrollbar" style=color:#FFFFFF;background-color:#282C34><code class=codeBlockLines_AclH><span class=token-line style=color:#FFFFFF><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><span class="token punctuation" style=color:#657b83>;</span><br></span></code></pre></div></div></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="theme-doc-footer-edit-meta-row row"><div class=editButtons_t0bR><a href=https://github.com/facebook/react-native-website/edit/main/docs/backhandler.md target=_blank rel="noopener noreferrer" class=theme-edit-this-page><svg fill=currentColor height=20 width=20 viewBox="0 0 40 40" class=iconEdit_bHB7 aria-hidden=true><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"/></g></svg>Edit page for next release</a><a 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