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<script src="https://snack.expo.io/embed.js" defer="defer"></script><title data-react-helmet="true">Learn the Basics · 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="Learn the Basics · React Native"><meta data-react-helmet="true" name="description" content="React Native is like React, but it uses native components instead of web components as building blocks. So to understand the basic structure of a React Native app, you need to understand some of the basic React concepts, like JSX, components, state, and props. If you already know React, you still need to learn some React-Native-specific stuff, like the native components. This tutorial is aimed at all audiences, whether you have React experience or not."><meta data-react-helmet="true" property="og:description" content="React Native is like React, but it uses native components instead of web components as building blocks. So to understand the basic structure of a React Native app, you need to understand some of the basic React concepts, like JSX, components, state, and props. If you already know React, you still need to learn some React-Native-specific stuff, like the native components. This tutorial is aimed at all audiences, whether you have React experience or not."><meta data-react-helmet="true" property="og:url" content="https://reactnative.dev/docs/tutorial"><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/tutorial"><link rel="stylesheet" href="/styles.fccefeba.css">
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href="/docs/next/tutorial">Next</a></li><li class="menu__list-item"><a aria-current="page" class="menu__link menu__link--active" href="/docs/tutorial">0.63</a></li><li class="menu__list-item"><a class="menu__link" href="/docs/0.62/tutorial">0.62</a></li><li class="menu__list-item"><a class="menu__link" href="/docs/0.61/tutorial">0.61</a></li><li class="menu__list-item"><a class="menu__link" href="/docs/0.60/tutorial">0.60</a></li><li class="menu__list-item"><a class="menu__link" href="/versions">All versions</a></li></ul></li><li 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_2UBv"><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">Learn the Basics</h1></header><div class="markdown"><p>React Native is like React, but it uses native components instead of web components as building blocks. So to understand the basic structure of a React Native app, you need to understand some of the basic React concepts, like JSX, components, <code>state</code>, and <code>props</code>. If you already know React, you still need to learn some React-Native-specific stuff, like the native components. This tutorial is aimed at all audiences, whether you have React experience or not.</p><p>Let's do this thing.</p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="hello-world"></a>Hello World<a aria-hidden="true" tabindex="-1" class="hash-link" href="#hello-world" title="Direct link to heading">#</a></h2><p>In accordance with the ancient traditions of our people, we must first build an app that does nothing except say "Hello, world!". Here it is:</p><div class="snack-player" data-snack-name="Hello World" data-snack-description="Example usage" data-snack-code="import%20React%20from%20'react'%3B%0Aimport%20%7B%20Text%2C%20View%20%7D%20from%20'react-native'%3B%0A%0Aconst%20HelloWorldApp%20%3D%20()%20%3D%3E%20%7B%0A%20%20return%20(%0A%20%20%20%20%3CView%0A%20%20%20%20%20%20style%3D%7B%7B%0A%20%20%20%20%20%20%20%20flex%3A%201%2C%0A%20%20%20%20%20%20%20%20justifyContent%3A%20%22center%22%2C%0A%20%20%20%20%20%20%20%20alignItems%3A%20%22center%22%0A%20%20%20%20%20%20%7D%7D%3E%0A%20%20%20%20%20%20%3CText%3EHello%2C%20world!%3C%2FText%3E%0A%20%20%20%20%3C%2FView%3E%0A%20%20)%0A%7D%0Aexport%20default%20HelloWorldApp%3B" 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>If you are feeling curious, you can play around with sample code directly in the web simulators. You can also paste it into your <code>App.js</code> file to create a real app on your local machine.</p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="whats-going-on-here"></a>What's going on here?<a aria-hidden="true" tabindex="-1" class="hash-link" href="#whats-going-on-here" title="Direct link to heading">#</a></h2><ol><li>First of all, we need to import <code>React</code> to be able to use <code>JSX</code>, which will then be transformed to the native components of each platform.</li><li>On line 2, we import the <code>Text</code> and <code>View</code> components from <code>react-native</code></li></ol><p>Then we find the <code>HelloWorldApp</code> function, which is a <a href="https://reactjs.org/docs/components-and-props.html#function-and-class-components" target="_blank" rel="noopener noreferrer">functional component</a> and behaves in the same way as in React for the web. This function returns a <code>View</code> component with some styles and a<code>Text</code> as its child.</p><p>The <code>Text</code> component allows us to render a text, while the <code>View</code> component renders a container. This container has several styles applied, let's analyze what each one is doing.</p><p>The first style that we find is <code>flex: 1</code>, the <a href="/docs/layout-props#flex"><code>flex</code></a> prop will define how your items are going to "fill" over the available space along your main axis. Since we only have one container, it will take all the available space of the parent component. In this case, it is the only component, so it will take all the available screen space.</p><p>The following style is <a href="/docs/layout-props#justifycontent"><code>justifyContent</code></a>: "center". This aligns children of a container in the center of the container's main axis and finally we have <a href="/docs/layout-props#alignitems"><code>alignItems</code></a>: "center", which align children of a container in the center of the container's cross axis.</p><p>Some of the things in here might not look like JavaScript to you. Don't panic. <em>This is the future</em>.</p><p>First of all, ES2015 (also known as ES6) is a set of improvements to JavaScript that is now part of the official standard, but not yet supported by all browsers, so often it isn't used yet in web development. React Native ships with ES2015 support, so you can use this stuff without worrying about compatibility. <code>import</code>, <code>export</code>, <code>const</code> and <code>from</code> in the example above are all ES2015 features. If you aren't familiar with ES2015, you can probably pick it up by reading through sample code like this tutorial has. If you want, <a href="https://babeljs.io/learn-es2015/" target="_blank" rel="noopener noreferrer">this page</a> has a good overview of ES2015 features.</p><p>The other unusual thing in this code example is <code><View><Text>Hello world!</Text></View></code>. This is JSX - a syntax for embedding XML within JavaScript. Many frameworks use a specialized templating language which lets you embed code inside markup language. In React, this is reversed. JSX lets you write your markup language inside code. It looks like HTML on the web, except instead of web things like <code><div></code> or <code><span></code>, you use React components. In this case, <code><Text></code> is a <a href="/docs/intro-react-native-components">Core Component</a> that displays some text and <code>View</code> is like the <code><div></code> or <code><span></code>.</p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="components"></a>Components<a aria-hidden="true" tabindex="-1" class="hash-link" href="#components" title="Direct link to heading">#</a></h2><p>So this code is defining <code>HelloWorldApp</code>, a new <code>Component</code>. When you're building a React Native app, you'll be making new components a lot. Anything you see on the screen is some sort of component.</p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="props"></a>Props<a aria-hidden="true" tabindex="-1" class="hash-link" href="#props" title="Direct link to heading">#</a></h2><p>Most components can be customized when they are created, with different parameters. These creation parameters are called props.</p><p>Your own components can also use <code>props</code>. This lets you make a single component that is used in many different places in your app, with slightly different properties in each place. Refer to <code>props.{NAME}</code> in your functional components or <code>this.props.{NAME}</code> in your class components. Here's an example:</p><div class="snack-player" data-snack-name="Hello Props" data-snack-description="Example usage" data-snack-code="import%20React%20from%20'react'%3B%0Aimport%20%7B%20Text%2C%20View%2C%20StyleSheet%20%7D%20from%20'react-native'%3B%0A%0Aconst%20styles%20%3D%20StyleSheet.create(%7B%0A%20%20center%3A%20%7B%0A%20%20%20%20alignItems%3A%20'center'%0A%20%20%7D%0A%7D)%0A%0Aconst%20Greeting%20%3D%20(props)%20%3D%3E%20%7B%0A%20%20return%20(%0A%20%20%20%20%3CView%20style%3D%7Bstyles.center%7D%3E%0A%20%20%20%20%20%20%3CText%3EHello%20%7Bprops.name%7D!%3C%2FText%3E%0A%20%20%20%20%3C%2FView%3E%0A%20%20)%3B%0A%7D%0A%0Aconst%20LotsOfGreetings%20%3D%20()%20%3D%3E%20%7B%0A%20%20return%20(%0A%20%20%20%20%3CView%20style%3D%7B%5Bstyles.center%2C%20%7Btop%3A%2050%7D%5D%7D%3E%0A%20%20%20%20%20%20%3CGreeting%20name%3D'Rexxar'%20%2F%3E%0A%20%20%20%20%20%20%3CGreeting%20name%3D'Jaina'%20%2F%3E%0A%20%20%20%20%20%20%3CGreeting%20name%3D'Valeera'%20%2F%3E%0A%20%20%20%20%3C%2FView%3E%0A%20%20)%3B%0A%7D%0A%0Aexport%20default%20LotsOfGreetings%3B" 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>Using <code>name</code> as a prop lets us customize the <code>Greeting</code> component, so we can reuse that component for each of our greetings. This example also uses the <code>Greeting</code> component in JSX. The power to do this is what makes React so cool.</p><p>The other new thing going on here is the <a href="/docs/view"><code>View</code></a> component. A <a href="/docs/view"><code>View</code></a> is useful as a container for other components, to help control style and layout.</p><p>With <code>props</code> and the basic <a href="/docs/text"><code>Text</code></a>, <a href="/docs/image"><code>Image</code></a>, and <a href="/docs/view"><code>View</code></a> components, you can build a wide variety of static screens. To learn how to make your app change over time, you need to <a href="#state">learn about State</a>.</p><h2><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="state"></a>State<a aria-hidden="true" tabindex="-1" class="hash-link" href="#state" title="Direct link to heading">#</a></h2><p>Unlike props <a href="https://reactjs.org/docs/components-and-props.html#props-are-read-only" target="_blank" rel="noopener noreferrer">that are read-only</a> and should not be modified, the <code>state</code> allows React components to change their output over time in response to user actions, network responses and anything else.</p><h4><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="whats-the-difference-between-state-and-props-in-react"></a>What's the difference between state and props in React?<a aria-hidden="true" tabindex="-1" class="hash-link" href="#whats-the-difference-between-state-and-props-in-react" title="Direct link to heading">#</a></h4><p>In a React component, the props are the variables that we pass from a parent component to a child component. Similarly, the state are also variables, with the difference that they are not passed as parameters, but rather that the component initializes and manages them internally.</p><h4><a aria-hidden="true" tabindex="-1" class="anchor enhancedAnchor_3pqN" id="are-there-differences-between-react-and-react-native-to-handle-the-state"></a>Are there differences between React and React Native to handle the state?<a aria-hidden="true" tabindex="-1" class="hash-link" href="#are-there-differences-between-react-and-react-native-to-handle-the-state" title="Direct link to heading">#</a></h4><div class="two-columns"><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 comment" style="color:#93a1a1">// ReactJS Counter Example using Hooks!</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token keyword" style="color:#c5a5c5">const</span><span class="token plain"> </span><span class="token function-variable function" style="color:#79b6f2">App</span><span class="token plain"> </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 operator" style="color:#fc929e">=></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">const</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">[</span><span class="token plain">count</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> setCount</span><span class="token punctuation" style="color:#657b83">]</span><span class="token plain"> </span><span class="token operator" style="color:#fc929e">=</span><span class="token plain"> </span><span class="token function" style="color:#79b6f2">useState</span><span class="token punctuation" style="color:#657b83">(</span><span class="token number" style="color:#5a9bcf">0</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" style="display:inline-block">
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</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 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 tag punctuation" style="color:#657b83"><</span><span class="token tag" style="color:#fc929e">div</span><span class="token tag" style="color:#fc929e"> </span><span class="token tag attr-name" style="color:#c5a5c5">className</span><span class="token tag attr-value punctuation" style="color:#657b83">=</span><span class="token tag attr-value punctuation" style="color:#657b83">"</span><span class="token tag attr-value" style="color:#8dc891">container</span><span class="token tag attr-value punctuation" style="color:#657b83">"</span><span class="token tag 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 tag punctuation" style="color:#657b83"><</span><span class="token tag" style="color:#fc929e">p</span><span class="token tag punctuation" style="color:#657b83">></span><span class="token plain">You clicked </span><span class="token punctuation" style="color:#657b83">{</span><span class="token plain">count</span><span class="token punctuation" style="color:#657b83">}</span><span class="token plain"> times</span><span class="token tag punctuation" style="color:#657b83"></</span><span class="token tag" style="color:#fc929e">p</span><span class="token tag 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 tag punctuation" style="color:#657b83"><</span><span class="token tag" style="color:#fc929e">button</span><span class="token tag" style="color:#fc929e"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token tag" style="color:#fc929e"> </span><span class="token tag attr-name" style="color:#c5a5c5">onClick</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#657b83">=</span><span class="token tag script language-javascript punctuation" style="color:#657b83">{</span><span class="token tag script language-javascript punctuation" style="color:#657b83">(</span><span class="token tag script language-javascript punctuation" style="color:#657b83">)</span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript operator" style="color:#fc929e">=></span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript function" style="color:#79b6f2">setCount</span><span class="token tag script language-javascript punctuation" style="color:#657b83">(</span><span class="token tag script language-javascript" style="color:#fc929e">count </span><span class="token tag script language-javascript operator" style="color:#fc929e">+</span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript number" style="color:#5a9bcf">1</span><span class="token tag script language-javascript punctuation" style="color:#657b83">)</span><span class="token tag script language-javascript punctuation" style="color:#657b83">}</span><span class="token tag punctuation" style="color:#657b83">></span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> Click me</span><span class="token operator" style="color:#fc929e">!</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#657b83"></</span><span class="token tag" style="color:#fc929e">button</span><span class="token tag 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 tag punctuation" style="color:#657b83"></</span><span class="token tag" style="color:#fc929e">div</span><span class="token tag 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 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 plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token comment" style="color:#93a1a1">// CSS</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">container </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"> display</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> flex</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"> justify</span><span class="token operator" style="color:#fc929e">-</span><span class="token plain">content</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> center</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"> align</span><span class="token operator" style="color:#fc929e">-</span><span class="token plain">items</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> center</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" style="display:inline-block">
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</span></div></div></div></div></div><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 comment" style="color:#93a1a1">// React Native Counter Example using Hooks!</span><span class="token plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token keyword" style="color:#c5a5c5">import</span><span class="token plain"> React</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"> useState </span><span class="token punctuation" style="color:#657b83">}</span><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">from</span><span class="token plain"> </span><span class="token string" style="color:#8dc891">'react'</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">import</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">{</span><span class="token plain"> View</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> Text</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> Button</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> StyleSheet </span><span class="token punctuation" style="color:#657b83">}</span><span class="token plain"> </span><span class="token keyword" style="color:#c5a5c5">from</span><span class="token plain"> </span><span class="token string" style="color:#8dc891">'react-native'</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" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token keyword" style="color:#c5a5c5">const</span><span class="token plain"> </span><span class="token function-variable function" style="color:#79b6f2">App</span><span class="token plain"> </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 operator" style="color:#fc929e">=></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">const</span><span class="token plain"> </span><span class="token punctuation" style="color:#657b83">[</span><span class="token plain">count</span><span class="token punctuation" style="color:#657b83">,</span><span class="token plain"> setCount</span><span class="token punctuation" style="color:#657b83">]</span><span class="token plain"> </span><span class="token operator" style="color:#fc929e">=</span><span class="token plain"> </span><span class="token function" style="color:#79b6f2">useState</span><span class="token punctuation" style="color:#657b83">(</span><span class="token number" style="color:#5a9bcf">0</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" style="display:inline-block">
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</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 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 tag punctuation" style="color:#657b83"><</span><span class="token tag class-name" style="color:#fac863">View</span><span class="token tag" style="color:#fc929e"> </span><span class="token tag attr-name" style="color:#c5a5c5">style</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#657b83">=</span><span class="token tag script language-javascript punctuation" style="color:#657b83">{</span><span class="token tag script language-javascript" style="color:#fc929e">styles</span><span class="token tag script language-javascript punctuation" style="color:#657b83">.</span><span class="token tag script language-javascript" style="color:#fc929e">container</span><span class="token tag script language-javascript punctuation" style="color:#657b83">}</span><span class="token tag 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 tag punctuation" style="color:#657b83"><</span><span class="token tag class-name" style="color:#fac863">Text</span><span class="token tag punctuation" style="color:#657b83">></span><span class="token plain">You clicked </span><span class="token punctuation" style="color:#657b83">{</span><span class="token plain">count</span><span class="token punctuation" style="color:#657b83">}</span><span class="token plain"> times</span><span class="token tag punctuation" style="color:#657b83"></</span><span class="token tag class-name" style="color:#fac863">Text</span><span class="token tag 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 tag punctuation" style="color:#657b83"><</span><span class="token tag class-name" style="color:#fac863">Button</span><span class="token tag" style="color:#fc929e"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token tag" style="color:#fc929e"> </span><span class="token tag attr-name" style="color:#c5a5c5">onPress</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#657b83">=</span><span class="token tag script language-javascript punctuation" style="color:#657b83">{</span><span class="token tag script language-javascript punctuation" style="color:#657b83">(</span><span class="token tag script language-javascript punctuation" style="color:#657b83">)</span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript operator" style="color:#fc929e">=></span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript function" style="color:#79b6f2">setCount</span><span class="token tag script language-javascript punctuation" style="color:#657b83">(</span><span class="token tag script language-javascript" style="color:#fc929e">count </span><span class="token tag script language-javascript operator" style="color:#fc929e">+</span><span class="token tag script language-javascript" style="color:#fc929e"> </span><span class="token tag script language-javascript number" style="color:#5a9bcf">1</span><span class="token tag script language-javascript punctuation" style="color:#657b83">)</span><span class="token tag script language-javascript punctuation" style="color:#657b83">}</span><span class="token tag" style="color:#fc929e"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token tag" style="color:#fc929e"> </span><span class="token tag attr-name" style="color:#c5a5c5">title</span><span class="token tag attr-value punctuation" style="color:#657b83">=</span><span class="token tag attr-value punctuation" style="color:#657b83">"</span><span class="token tag attr-value" style="color:#8dc891">Click me!</span><span class="token tag attr-value punctuation" style="color:#657b83">"</span><span class="token tag" style="color:#fc929e"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token tag" style="color:#fc929e"> </span><span class="token tag 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 tag punctuation" style="color:#657b83"></</span><span class="token tag class-name" style="color:#fac863">View</span><span class="token tag 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 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 plain"></span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain" style="display:inline-block">
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</span></div><div class="token-line" style="color:#FFFFFF;background:#282C34"><span class="token plain"></span><span class="token comment" style="color:#93a1a1">// React Native Styles</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">const</span><span class="token plain"> styles </span><span class="token operator" style="color:#fc929e">=</span><span class="token plain"> StyleSheet</span><span class="token punctuation" style="color:#657b83">.</span><span class="token function" style="color:#79b6f2">create</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"> container</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"> flex</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> </span><span class="token number" style="color:#5a9bcf">1</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"> justifyContent</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> </span><span class="token string" style="color:#8dc891">'center'</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"> alignItems</span><span class="token punctuation" style="color:#657b83">:</span><span class="token plain"> </span><span class="token string" style="color:#8dc891">'center'</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 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></div><p>As shown in the image, there is no difference in handling the <code>state</code> between <a href="https://reactjs.org/docs/state-and-lifecycle.html" target="_blank" rel="noopener noreferrer">React</a> and <code>React Native</code>. You can use the state of your components both in classes and in functional components using <a href="https://reactjs.org/docs/hooks-intro.html" target="_blank" rel="noopener noreferrer">hooks</a>!</p><p>In the following example we will show the same above counter example using classes.</p><div class="snack-player" data-snack-name="Hello Classes" data-snack-description="Example usage" data-snack-code="import%20React%2C%20%7B%20Component%20%7D%20from%20'react'%0Aimport%20%7B%0A%20%20StyleSheet%2C%0A%20%20TouchableOpacity%2C%0A%20%20Text%2C%0A%20%20View%2C%0A%7D%20from%20'react-native'%0A%0Aclass%20App%20extends%20Component%20%7B%0A%20%20state%20%3D%20%7B%0A%20%20%20%20count%3A%200%0A%20%20%7D%0A%0A%20%20onPress%20%3D%20()%20%3D%3E%20%7B%0A%20%20%20%20this.setState(%7B%0A%20%20%20%20%20%20count%3A%20this.state.count%20%2B%201%0A%20%20%20%20%7D)%0A%20%20%7D%0A%0A%20render()%20%7B%0A%20%20%20%20return%20(%0A%20%20%20%20%20%20%3CView%20style%3D%7Bstyles.container%7D%3E%0A%20%20%20%20%20%20%20%20%3CTouchableOpacity%0A%20%20%20%20%20%20%20%20%20style%3D%7Bstyles.button%7D%0A%20%20%20%20%20%20%20%20%20onPress%3D%7Bthis.onPress%7D%0A%20%20%20%20%20%20%20%20%3E%0A%20%20%20%20%20%20%20%20%20%3CText%3EClick%20me%3C%2FText%3E%0A%20%20%20%20%20%20%20%20%3C%2FTouchableOpacity%3E%0A%20%20%20%20%20%20%20%20%3CView%3E%0A%20%20%20%20%20%20%20%20%20%20%3CText%3E%0A%20%20%20%20%20%20%20%20%20%20%20%20You%20clicked%20%7B%20this.state.count%20%7D%20times%0A%20%20%20%20%20%20%20%20%20%20%3C%2FText%3E%0A%20%20%20%20%20%20%20%20%3C%2FView%3E%0A%20%20%20%20%20%20%3C%2FView%3E%0A%20%20%20%20)%0A%20%20%7D%0A%7D%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%20justifyContent%3A%20'center'%2C%0A%20%20%20%20alignItems%3A%20'center'%2C%0A%20%20%7D%2C%0A%20%20button%3A%20%7B%0A%20%20%20%20alignItems%3A%20'center'%2C%0A%20%20%20%20backgroundColor%3A%20'%23DDDDDD'%2C%0A%20%20%20%20padding%3A%2010%2C%0A%20%20%20%20marginBottom%3A%2010%0A%20%20%7D%0A%7D)%0A%0Aexport%20default%20App%3B" 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></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/tutorial.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="2020-12-30T11:25:33.000Z" class="docLastUpdatedAt_1gIo">12/30/2020</time></small></em></div></div></div><div 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