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<script src="https://snack.expo.io/embed.js" defer="defer"></script><title data-react-helmet="true">State · React Native</title><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="0.60"><meta data-react-helmet="true" name="docsearch:docusaurus_tag" content="docs-default-0.60"><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="State · React Native"><meta data-react-helmet="true" name="description" content="There are two types of data that control a component: props and state. props are set by the parent and they are fixed throughout the lifetime of a component. For data that is going to change, we have to use state."><meta data-react-helmet="true" property="og:description" content="There are two types of data that control a component: props and state. props are set by the parent and they are fixed throughout the lifetime of a component. For data that is going to change, we have to use state."><meta data-react-helmet="true" property="og:url" content="https://reactnative.dev/docs/0.60/state"><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/0.60/state"><link rel="stylesheet" href="/styles.f56da522.css">
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<nav aria-label="Skip navigation links"><button type="button" tabindex="0" class="skipToContent_3aLp">Skip to main content</button></nav><nav class="navbar navbar--fixed-top navbar--dark"><div class="navbar__inner"><div class="navbar__items"><div aria-label="Navigation bar toggle" class="navbar__toggle" role="button" tabindex="0"><svg aria-label="Menu" width="30" height="30" viewBox="0 0 30 30" role="img" focusable="false"><title>Menu</title><path stroke="currentColor" stroke-linecap="round" stroke-miterlimit="10" stroke-width="2" d="M4 7h22M4 15h22M4 23h22"></path></svg></div><a class="navbar__brand" href="/"><img src="/img/header_logo.svg" alt="React Native" class="themedImage_phiS themedImage--light_VJaY navbar__logo"><img src="/img/header_logo.svg" alt="React Native" class="themedImage_phiS themedImage--dark_1NF3 navbar__logo"><strong class="navbar__title">React Native</strong></a><div class="navbar__item dropdown dropdown--hoverable dropdown--left"><a class="navbar__item 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class="menu__list-item"><a href="https://github.com/facebook/react-native" target="_blank" rel="noopener noreferrer" class="menu__link navbar-github-link" aria-label="GitHub repository"></a></li></ul></div></div></div></nav><div class="main-wrapper"><div class="docPage_1mVJ"><main class="docMainContainer_1zi2"><div class="container padding-vert--lg docItemWrapper_1hMI"><div class="row"><div class="col docItemCol_2AGf"><div class="alert alert--warning margin-bottom--md" role="alert"><div>This is documentation for React Native <strong>0.60</strong>, which is no longer actively maintained.</div><div class="margin-top--md">For up-to-date documentation, see the <strong><a href="/docs/state">latest version</a></strong> (0.64).</div></div><div class="docItemContainer_1tAC"><article><div><span class="badge badge--secondary">Version: 0.60</span></div><header><h1 class="docTitle_cWlf">State</h1></header><div class="markdown"><p>There are two types of data that control a component: <code>props</code> and <code>state</code>. <code>props</code> are set by the parent and they are fixed throughout the lifetime of a component. For data that is going to change, we have to use <code>state</code>.</p><p>In general, you should initialize <code>state</code> in the constructor, and then call <code>setState</code> when you want to change it.</p><p>For example, let&#x27;s say we want to make text that blinks all the time. The text itself gets set once when the blinking component gets created, so the text itself is a <code>prop</code>. The &quot;whether the text is currently on or off&quot; changes over time, so that should be kept in <code>state</code>.</p><div class="snack-player" data-snack-name="State" data-snack-description="Example usage" data-snack-code="import%20React%2C%20%7B%20Component%20%7D%20from%20&#x27;react&#x27;%3B%0Aimport%20%7B%20Text%2C%20View%20%7D%20from%20&#x27;react-native&#x27;%3B%0A%0Aclass%20Blink%20extends%20Component%20%7B%0A%0A%20%20componentDidMount()%7B%0A%20%20%20%20%2F%2F%20Toggle%20the%20state%20every%20second%0A%20%20%20%20setInterval(()%20%3D%3E%20(%0A%20%20%20%20%20%20this.setState(previousState%20%3D%3E%20(%0A%20%20%20%20%20%20%20%20%7B%20isShowingText%3A%20!previousState.isShowingText%20%7D%0A%20%20%20%20%20%20))%0A%20%20%20%20)%2C%201000)%3B%0A%20%20%7D%0A%0A%20%20%2F%2Fstate%20object%0A%20%20state%20%3D%20%7B%20isShowingText%3A%20true%20%7D%3B%0A%0A%20%20render()%20%7B%0A%20%20%20%20if%20(!this.state.isShowingText)%20%7B%0A%20%20%20%20%20%20return%20null%3B%0A%20%20%20%20%7D%0A%0A%20%20%20%20return%20(%0A%20%20%20%20%20%20%3CText%3E%7Bthis.props.text%7D%3C%2FText%3E%0A%20%20%20%20)%3B%0A%20%20%7D%0A%7D%0A%0Aexport%20default%20class%20BlinkApp%20extends%20Component%20%7B%0A%20%20render()%20%7B%0A%20%20%20%20return%20(%0A%20%20%20%20%20%20%3CView%3E%0A%20%20%20%20%20%20%20%20%3CBlink%20text%3D&#x27;I%20love%20to%20blink&#x27;%20%2F%3E%0A%20%20%20%20%20%20%20%20%3CBlink%20text%3D&#x27;Yes%20blinking%20is%20so%20great&#x27;%20%2F%3E%0A%20%20%20%20%20%20%20%20%3CBlink%20text%3D&#x27;Why%20did%20they%20ever%20take%20this%20out%20of%20HTML&#x27;%20%2F%3E%0A%20%20%20%20%20%20%20%20%3CBlink%20text%3D&#x27;Look%20at%20me%20look%20at%20me%20look%20at%20me&#x27;%20%2F%3E%0A%20%20%20%20%20%20%3C%2FView%3E%0A%20%20%20%20)%3B%0A%20%20%7D%0A%7D" data-snack-dependencies="" data-snack-platform="web" data-snack-supported-platforms="ios,android,web" data-snack-theme="light" data-snack-preview="true" data-snack-loading="lazy"></div><p>In a real application, you probably won&#x27;t be setting state with a timer. You might set state when you have new data from the server, or from user input. You can also use a state container like <a href="https://redux.js.org/" target="_blank" rel="noopener noreferrer">Redux</a> or <a href="https://mobx.js.org/" target="_blank" rel="noopener noreferrer">Mobx</a> to control your data flow. In that case you would use Redux or Mobx to modify your state rather than calling <code>setState</code> directly.</p><p>When setState is called, BlinkApp will re-render its Component. By calling setState within the Timer, the component will re-render every time the Timer ticks.</p><p>State works the same way as it does in React, so for more details on handling state, you can look at the <a href="https://reactjs.org/docs/react-component.html#setstate" target="_blank" rel="noopener noreferrer">React.Component API</a>. At this point, you might be annoyed that most of our examples so far use the default text color. To customize the text color, you will have to <a href="/docs/0.60/style">learn about Style</a>.</p></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-0.60/state.md" target="_blank" rel="noreferrer noopener"><svg fill="currentColor" height="1.2em" width="1.2em" preserveAspectRatio="xMidYMid meet" role="img" viewBox="0 0 40 40" class="iconEdit_2Hwv"><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"></div><div class="pagination-nav__item pagination-nav__item--next"></div></nav></div></div></div><div class="col col--3"><div class="tableOfContents_1zTD thin-scrollbar"></div></div></div></div></main></div></div><footer class="footer footer--dark"><div class="container"><div class="row footer__links"><div class="col footer__col"><h4 class="footer__title">Docs</h4><ul class="footer__items"><li class="footer__item"><a class="footer__link-item" href="/docs/getting-started">Getting Started</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/tutorial">Tutorial</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/components-and-apis">Components and APIs</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/more-resources">More Resources</a></li></ul></div><div class="col footer__col"><h4 class="footer__title">Community</h4><ul class="footer__items"><li class="footer__item"><a class="footer__link-item" href="/help">The React Native Community</a></li><li class="footer__item"><a class="footer__link-item" href="/showcase">Who&#x27;s using React Native?</a></li><li class="footer__item"><a href="https://stackoverflow.com/questions/tagged/react-native" target="_blank" rel="noopener noreferrer" class="footer__link-item">Ask Questions on Stack Overflow</a></li><li class="footer__item"><a href="https://github.com/facebook/react-native/blob/master/CONTRIBUTING.md" target="_blank" rel="noopener noreferrer" class="footer__link-item">Contributor Guide</a></li><li class="footer__item"><a href="https://dev.to/t/reactnative" target="_blank" rel="noopener noreferrer" class="footer__link-item">DEV Community</a></li></ul></div><div class="col footer__col"><h4 class="footer__title">Find us</h4><ul class="footer__items"><li class="footer__item"><a class="footer__link-item" href="/blog">Blog</a></li><li class="footer__item"><a href="https://twitter.com/reactnative" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter</a></li><li class="footer__item"><a href="https://github.com/facebook/react-native" target="_blank" rel="noopener noreferrer" class="footer__link-item">GitHub</a></li></ul></div><div class="col footer__col"><h4 class="footer__title">More</h4><ul class="footer__items"><li class="footer__item"><a href="https://reactjs.org/" target="_blank" rel="noopener noreferrer" class="footer__link-item">React</a></li><li class="footer__item"><a href="https://opensource.facebook.com/legal/privacy" target="_blank" rel="noopener noreferrer" class="footer__link-item">Privacy Policy</a></li><li class="footer__item"><a href="https://opensource.facebook.com/legal/terms" target="_blank" rel="noopener noreferrer" class="footer__link-item">Terms of Service</a></li></ul></div></div><div class="footer__bottom text--center"><div class="margin-bottom--sm"><a href="https://opensource.facebook.com" target="_blank" rel="noopener noreferrer" class="footerLogoLink_3cAK"><img class="footer__logo" alt="Facebook Open Source Logo" src="/img/oss_logo.png"></a></div><div class="footer__copyright">Copyright © 2021 Facebook, Inc.</div></div></div></footer></div>
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