mirror of
https://github.com/facebook/react-native.git
synced 2025-11-01 09:14:26 +00:00
Website Deployment Script
92 lines
36 KiB
HTML
92 lines
36 KiB
HTML
<!DOCTYPE html><html><head><title>FlatList - React Native</title><meta charset="utf-8"><meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"><meta name="viewport" content="width=device-width"><meta property="fb:app_id" content="1677033832619985"><meta property="fb:admins" content="121800083"><meta property="og:site_name" content="React Native"><meta property="og:title" content="FlatList - React Native"><meta property="og:url" content="https://facebook.github.io/react-native/index.html"><meta property="og:image" content="https://facebook.github.io/react-native/img/opengraph.png"><meta property="og:description" content="A framework for building native apps using React"><meta name="twitter:site" content="@reactnative"><meta name="twitter:card" content="summary_large_image"><meta property="og:type" content="website"><base href="/react-native/"><link rel="stylesheet" href="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.css"><link rel="shortcut icon" href="img/favicon.png?2"><link rel="stylesheet" href="css/react-native.css"><link rel="stylesheet" href="css/prism.css"><link rel="alternate" type="application/rss+xml" title="React Native Blog" href="https://facebook.github.io/react-native/blog/feed.xml"><link href="//cdn-images.mailchimp.com/embedcode/horizontal-slim-10_7.css" rel="stylesheet" type="text/css"><script type="text/javascript" src="//use.typekit.net/vqa1hcx.js"></script><script type="text/javascript">try{Typekit.load();}catch(e){}</script></head><body><script>window.fbAsyncInit = function() {FB.init({appId:'1677033832619985',xfbml:true,version:'v2.7'});};(function(d, s, id){var js, fjs = d.getElementsByTagName(s)[0];if (d.getElementById(id)) {return;}js = d.createElement(s); js.id = id;js.src = '//connect.facebook.net/en_US/sdk.js';fjs.parentNode.insertBefore(js, fjs);}(document, 'script','facebook-jssdk'));</script><script>window.twttr=(function(d,s, id){var js,fjs=d.getElementsByTagName(s)[0],t=window.twttr||{};if(d.getElementById(id))return t;js=d.createElement(s);js.id=id;js.src='https://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js, fjs);t._e = [];t.ready = function(f) {t._e.push(f);};return t;}(document, 'script', 'twitter-wjs'));</script><div class="container"><div class="nav-main"><div class="wrap"><a class="nav-home" href=""><img src="img/header_logo.png">React Native</a><a class="nav-version" href="/react-native/versions.html">0.49</a><div class="nav-site-wrapper"><ul class="nav-site nav-site-internal"><li><a href="docs/getting-started.html" class="active" data-target=".nav-docs">Docs</a></li><li><a href="/react-native/support.html" class="">Community</a></li><li><a href="/react-native/blog/" class="">Blog</a></li></ul><div class="algolia-search-wrapper"><input id="algolia-doc-search" tabindex="0" type="text" placeholder="Search docs..."></div><ul class="nav-site nav-site-external"><li><a href="https://github.com/facebook/react-native" class="">GitHub</a></li><li><a href="http://facebook.github.io/react" class="">React</a></li></ul></div></div></div><section class="content wrap documentationContent"><div class="nav-docs"><div class="nav-docs-viewport"><div class="nav-docs-section"><h3>The Basics</h3><ul><li><a style="margin-left:10px;" class="" href="docs/getting-started.html">Getting Started</a></li><li><a style="margin-left:10px;" class="" href="docs/tutorial.html">Learn the Basics</a></li><li><a style="margin-left:10px;" class="" href="docs/props.html">Props</a></li><li><a style="margin-left:10px;" class="" href="docs/state.html">State</a></li><li><a style="margin-left:10px;" class="" href="docs/style.html">Style</a></li><li><a style="margin-left:10px;" class="" href="docs/height-and-width.html">Height and Width</a></li><li><a style="margin-left:10px;" class="" href="docs/flexbox.html">Layout with Flexbox</a></li><li><a style="margin-left:10px;" class="" href="docs/handling-text-input.html">Handling Text Input</a></li><li><a style="margin-left:10px;" class="" href="docs/handling-touches.html">Handling Touches</a></li><li><a style="margin-left:10px;" class="" href="docs/using-a-scrollview.html">Using a ScrollView</a></li><li><a style="margin-left:10px;" class="" href="docs/using-a-listview.html">Using List Views</a></li><li><a style="margin-left:10px;" class="" href="docs/network.html">Networking</a></li><li><a style="margin-left:10px;" class="" href="docs/more-resources.html">More Resources</a></li></ul></div><div class="nav-docs-section"><h3>Guides</h3><ul><li><a style="margin-left:10px;" class="" href="docs/components-and-apis.html">Components and APIs</a></li><li><a style="margin-left:10px;" class="" href="docs/platform-specific-code.html">Platform Specific Code</a></li><li><a style="margin-left:10px;" class="" href="docs/navigation.html">Navigating Between Screens</a></li><li><a style="margin-left:10px;" class="" href="docs/images.html">Images</a></li><li><a style="margin-left:10px;" class="" href="docs/animations.html">Animations</a></li><li><a style="margin-left:10px;" class="" href="docs/accessibility.html">Accessibility</a></li><li><a style="margin-left:10px;" class="" href="docs/improvingux.html">Improving User Experience</a></li><li><a style="margin-left:10px;" class="" href="docs/timers.html">Timers</a></li><li><a style="margin-left:10px;" class="" href="docs/debugging.html">Debugging</a></li><li><a style="margin-left:10px;" class="" href="docs/performance.html">Performance</a></li><li><a style="margin-left:10px;" class="" href="docs/gesture-responder-system.html">Gesture Responder System</a></li><li><a style="margin-left:10px;" class="" href="docs/javascript-environment.html">JavaScript Environment</a></li><li><a style="margin-left:10px;" class="" href="docs/direct-manipulation.html">Direct Manipulation</a></li><li><a style="margin-left:10px;" class="" href="docs/colors.html">Color Reference</a></li><li><a style="margin-left:10px;" class="" href="docs/integration-with-existing-apps.html">Integration with Existing Apps</a></li><li><a style="margin-left:10px;" class="" href="docs/running-on-device.html">Running On Device</a></li><li><a style="margin-left:10px;" class="" href="docs/upgrading.html">Upgrading to new React Native versions</a></li><li><a style="margin-left:10px;" class="" href="docs/troubleshooting.html">Troubleshooting</a></li></ul></div><div class="nav-docs-section"><h3>Guides (iOS)</h3><ul><li><a style="margin-left:10px;" class="" href="docs/native-modules-ios.html">Native Modules</a></li><li><a style="margin-left:10px;" class="" href="docs/native-components-ios.html">Native UI Components</a></li><li><a style="margin-left:10px;" class="" href="docs/linking-libraries-ios.html">Linking Libraries</a></li><li><a style="margin-left:10px;" class="" href="docs/running-on-simulator-ios.html">Running On Simulator</a></li><li><a style="margin-left:10px;" class="" href="docs/communication-ios.html">Communication between native and React Native</a></li><li><a style="margin-left:10px;" class="" href="docs/building-for-apple-tv.html">Building For Apple TV</a></li><li><a style="margin-left:10px;" class="" href="docs/app-extensions.html">App Extensions</a></li></ul></div><div class="nav-docs-section"><h3>Guides (Android)</h3><ul><li><a style="margin-left:10px;" class="" href="docs/native-modules-android.html">Native Modules</a></li><li><a style="margin-left:10px;" class="" href="docs/native-components-android.html">Native UI Components</a></li><li><a style="margin-left:10px;" class="" href="docs/headless-js-android.html">Headless JS</a></li><li><a style="margin-left:10px;" class="" href="docs/signed-apk-android.html">Generating Signed APK</a></li><li><a style="margin-left:10px;" class="" href="docs/android-building-from-source.html">Building React Native from source</a></li></ul></div><div class="nav-docs-section"><h3>Contributing</h3><ul><li><a style="margin-left:10px;" class="" href="docs/contributing.html">How to Contribute</a></li><li><a style="margin-left:10px;" class="" href="docs/maintainers.html">What to Expect from Maintainers</a></li><li><a style="margin-left:10px;" class="" href="docs/testing.html">Testing your Changes</a></li><li><a style="margin-left:10px;" class="" href="docs/understanding-cli.html">Understanding the CLI</a></li></ul></div><div class="nav-docs-section"><h3>components</h3><ul><li><a style="margin-left:10px;" class="" href="docs/activityindicator.html">ActivityIndicator</a></li><li><a style="margin-left:10px;" class="" href="docs/button.html">Button</a></li><li><a style="margin-left:10px;" class="" href="docs/checkbox.html">CheckBox</a></li><li><a style="margin-left:10px;" class="" href="docs/datepickerios.html">DatePickerIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/drawerlayoutandroid.html">DrawerLayoutAndroid</a></li><li><a style="margin-left:10px;" class="active" href="docs/flatlist.html">FlatList</a></li><li><a style="margin-left:10px;" class="" href="docs/image.html">Image</a></li><li><a style="margin-left:10px;" class="" href="docs/keyboardavoidingview.html">KeyboardAvoidingView</a></li><li><a style="margin-left:10px;" class="" href="docs/listview.html">ListView</a></li><li><a style="margin-left:10px;" class="" href="docs/maskedviewios.html">MaskedViewIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/modal.html">Modal</a></li><li><a style="margin-left:10px;" class="" href="docs/navigatorios.html">NavigatorIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/picker.html">Picker</a></li><li><a style="margin-left:10px;" class="" href="docs/pickerios.html">PickerIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/progressbarandroid.html">ProgressBarAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/progressviewios.html">ProgressViewIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/refreshcontrol.html">RefreshControl</a></li><li><a style="margin-left:10px;" class="" href="docs/scrollview.html">ScrollView</a></li><li><a style="margin-left:10px;" class="" href="docs/sectionlist.html">SectionList</a></li><li><a style="margin-left:10px;" class="" href="docs/segmentedcontrolios.html">SegmentedControlIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/slider.html">Slider</a></li><li><a style="margin-left:10px;" class="" href="docs/snapshotviewios.html">SnapshotViewIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/statusbar.html">StatusBar</a></li><li><a style="margin-left:10px;" class="" href="docs/switch.html">Switch</a></li><li><a style="margin-left:10px;" class="" href="docs/tabbarios.html">TabBarIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/tabbarios-item.html">TabBarIOS.Item</a></li><li><a style="margin-left:10px;" class="" href="docs/text.html">Text</a></li><li><a style="margin-left:10px;" class="" href="docs/textinput.html">TextInput</a></li><li><a style="margin-left:10px;" class="" href="docs/toolbarandroid.html">ToolbarAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/touchablehighlight.html">TouchableHighlight</a></li><li><a style="margin-left:10px;" class="" href="docs/touchablenativefeedback.html">TouchableNativeFeedback</a></li><li><a style="margin-left:10px;" class="" href="docs/touchableopacity.html">TouchableOpacity</a></li><li><a style="margin-left:10px;" class="" href="docs/touchablewithoutfeedback.html">TouchableWithoutFeedback</a></li><li><a style="margin-left:10px;" class="" href="docs/view.html">View</a></li><li><a style="margin-left:10px;" class="" href="docs/viewpagerandroid.html">ViewPagerAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/virtualizedlist.html">VirtualizedList</a></li><li><a style="margin-left:10px;" class="" href="docs/webview.html">WebView</a></li></ul></div><div class="nav-docs-section"><h3>APIs</h3><ul><li><a style="margin-left:10px;" class="" href="docs/accessibilityinfo.html">AccessibilityInfo</a></li><li><a style="margin-left:10px;" class="" href="docs/actionsheetios.html">ActionSheetIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/alert.html">Alert</a></li><li><a style="margin-left:10px;" class="" href="docs/alertios.html">AlertIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/animated.html">Animated</a></li><li><a style="margin-left:10px;" class="" href="docs/appregistry.html">AppRegistry</a></li><li><a style="margin-left:10px;" class="" href="docs/appstate.html">AppState</a></li><li><a style="margin-left:10px;" class="" href="docs/asyncstorage.html">AsyncStorage</a></li><li><a style="margin-left:10px;" class="" href="docs/backandroid.html">BackAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/backhandler.html">BackHandler</a></li><li><a style="margin-left:10px;" class="" href="docs/cameraroll.html">CameraRoll</a></li><li><a style="margin-left:10px;" class="" href="docs/clipboard.html">Clipboard</a></li><li><a style="margin-left:10px;" class="" href="docs/datepickerandroid.html">DatePickerAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/dimensions.html">Dimensions</a></li><li><a style="margin-left:10px;" class="" href="docs/easing.html">Easing</a></li><li><a style="margin-left:10px;" class="" href="docs/geolocation.html">Geolocation</a></li><li><a style="margin-left:10px;" class="" href="docs/imageeditor.html">ImageEditor</a></li><li><a style="margin-left:10px;" class="" href="docs/imagepickerios.html">ImagePickerIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/imagestore.html">ImageStore</a></li><li><a style="margin-left:10px;" class="" href="docs/interactionmanager.html">InteractionManager</a></li><li><a style="margin-left:10px;" class="" href="docs/keyboard.html">Keyboard</a></li><li><a style="margin-left:10px;" class="" href="docs/layoutanimation.html">LayoutAnimation</a></li><li><a style="margin-left:10px;" class="" href="docs/linking.html">Linking</a></li><li><a style="margin-left:10px;" class="" href="docs/netinfo.html">NetInfo</a></li><li><a style="margin-left:10px;" class="" href="docs/panresponder.html">PanResponder</a></li><li><a style="margin-left:10px;" class="" href="docs/permissionsandroid.html">PermissionsAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/pixelratio.html">PixelRatio</a></li><li><a style="margin-left:10px;" class="" href="docs/pushnotificationios.html">PushNotificationIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/settings.html">Settings</a></li><li><a style="margin-left:10px;" class="" href="docs/share.html">Share</a></li><li><a style="margin-left:10px;" class="" href="docs/statusbarios.html">StatusBarIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/stylesheet.html">StyleSheet</a></li><li><a style="margin-left:10px;" class="" href="docs/systrace.html">Systrace</a></li><li><a style="margin-left:10px;" class="" href="docs/timepickerandroid.html">TimePickerAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/toastandroid.html">ToastAndroid</a></li><li><a style="margin-left:10px;" class="" href="docs/vibration.html">Vibration</a></li><li><a style="margin-left:10px;" class="" href="docs/vibrationios.html">VibrationIOS</a></li><li><a style="margin-left:10px;" class="" href="docs/layout-props.html">Layout Props</a></li><li><a style="margin-left:10px;" class="" href="docs/shadow-props.html">Shadow Props</a></li><li><a style="margin-left:10px;" class="" href="docs/viewproptypes.html">ViewPropTypes</a></li><li><a style="margin-left:10px;" class="" href="docs/viewstyleproptypes.html">ViewStylePropTypes</a></li><li><a style="margin-left:10px;" class="" href="docs/textstyleproptypes.html">TextStylePropTypes</a></li><li><a style="margin-left:10px;" class="" href="docs/imagestyleproptypes.html">ImageStylePropTypes</a></li></ul></div></div></div><div class="inner-content"><a id="content"></a><h1><a class="anchor" name="flatlist"></a>FlatList <a class="hash-link" href="docs/flatlist.html#flatlist">#</a></h1><div><div><p>A performant interface for rendering simple, flat lists, supporting the most handy features:</p><ul><li>Fully cross-platform.</li><li>Optional horizontal mode.</li><li>Configurable viewability callbacks.</li><li>Header support.</li><li>Footer support.</li><li>Separator support.</li><li>Pull to Refresh.</li><li>Scroll loading.</li><li>ScrollToIndex support.</li></ul><p>If you need section support, use <a href="docs/sectionlist.html" target="_blank"><code><SectionList></code></a>.</p><p>Minimal Example:</p><div class="prism language-javascript"><span class="token operator"><</span>FlatList
|
|
data<span class="token operator">=</span><span class="token punctuation">{</span><span class="token punctuation">[</span><span class="token punctuation">{</span>key<span class="token punctuation">:</span> <span class="token string">'a'</span><span class="token punctuation">}</span><span class="token punctuation">,</span> <span class="token punctuation">{</span>key<span class="token punctuation">:</span> <span class="token string">'b'</span><span class="token punctuation">}</span><span class="token punctuation">]</span><span class="token punctuation">}</span>
|
|
renderItem<span class="token operator">=</span><span class="token punctuation">{</span><span class="token punctuation">(</span><span class="token punctuation">{</span>item<span class="token punctuation">}</span><span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token operator"><</span>Text<span class="token operator">></span><span class="token punctuation">{</span>item<span class="token punctuation">.</span>key<span class="token punctuation">}</span><span class="token operator"><</span><span class="token operator">/</span>Text<span class="token operator">></span><span class="token punctuation">}</span>
|
|
<span class="token operator">/</span><span class="token operator">></span></div><p>More complex example demonstrating <code>PureComponent</code> usage for perf optimization and avoiding bugs.</p><ul><li>By binding the <code>onPressItem</code> handler, the props will remain <code>===</code> and <code>PureComponent</code> will
|
|
prevent wasteful re-renders unless the actual <code>id</code>, <code>selected</code>, or <code>title</code> props change, even
|
|
if the inner <code>SomeOtherWidget</code> has no such optimizations.</li><li>By passing <code>extraData={this.state}</code> to <code>FlatList</code> we make sure <code>FlatList</code> itself will re-render
|
|
when the <code>state.selected</code> changes. Without setting this prop, <code>FlatList</code> would not know it
|
|
needs to re-render any items because it is also a <code>PureComponent</code> and the prop comparison will
|
|
not show any changes.</li><li><code>keyExtractor</code> tells the list to use the <code>id</code>s for the react keys.</li></ul><div class="prism language-javascript"><span class="token keyword">class</span> <span class="token class-name">MyListItem</span> <span class="token keyword">extends</span> <span class="token class-name">React<span class="token punctuation">.</span>PureComponent</span> <span class="token punctuation">{</span>
|
|
_onPress <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
|
|
<span class="token keyword">this</span><span class="token punctuation">.</span>props<span class="token punctuation">.</span><span class="token function">onPressItem</span><span class="token punctuation">(</span><span class="token keyword">this</span><span class="token punctuation">.</span>props<span class="token punctuation">.</span>id<span class="token punctuation">)</span><span class="token punctuation">;</span>
|
|
<span class="token punctuation">}</span><span class="token punctuation">;</span>
|
|
|
|
<span class="token function">render</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
|
|
<span class="token keyword">return</span> <span class="token punctuation">(</span>
|
|
<span class="token operator"><</span>SomeOtherWidget
|
|
<span class="token punctuation">{</span><span class="token operator">...</span><span class="token keyword">this</span><span class="token punctuation">.</span>props<span class="token punctuation">}</span>
|
|
onPress<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>_onPress<span class="token punctuation">}</span>
|
|
<span class="token operator">/</span><span class="token operator">></span>
|
|
<span class="token punctuation">)</span>
|
|
<span class="token punctuation">}</span>
|
|
<span class="token punctuation">}</span>
|
|
|
|
<span class="token keyword">class</span> <span class="token class-name">MyList</span> <span class="token keyword">extends</span> <span class="token class-name">React<span class="token punctuation">.</span>PureComponent</span> <span class="token punctuation">{</span>
|
|
state <span class="token operator">=</span> <span class="token punctuation">{</span>selected<span class="token punctuation">:</span> <span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Map</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">:</span> Map<span class="token operator"><</span>string<span class="token punctuation">,</span> boolean<span class="token operator">></span><span class="token punctuation">)</span><span class="token punctuation">}</span><span class="token punctuation">;</span>
|
|
|
|
_keyExtractor <span class="token operator">=</span> <span class="token punctuation">(</span>item<span class="token punctuation">,</span> index<span class="token punctuation">)</span> <span class="token operator">=></span> item<span class="token punctuation">.</span>id<span class="token punctuation">;</span>
|
|
|
|
_onPressItem <span class="token operator">=</span> <span class="token punctuation">(</span>id<span class="token punctuation">:</span> string<span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
|
|
<span class="token comment" spellcheck="true"> // updater functions are preferred for transactional updates
|
|
</span> <span class="token keyword">this</span><span class="token punctuation">.</span><span class="token function">setState</span><span class="token punctuation">(</span><span class="token punctuation">(</span>state<span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
|
|
<span class="token comment" spellcheck="true"> // copy the map rather than modifying state.
|
|
</span> <span class="token keyword">const</span> selected <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Map</span><span class="token punctuation">(</span>state<span class="token punctuation">.</span>selected<span class="token punctuation">)</span><span class="token punctuation">;</span>
|
|
selected<span class="token punctuation">.</span><span class="token keyword">set</span><span class="token punctuation">(</span>id<span class="token punctuation">,</span> <span class="token operator">!</span>selected<span class="token punctuation">.</span><span class="token keyword">get</span><span class="token punctuation">(</span>id<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token comment" spellcheck="true"> // toggle
|
|
</span> <span class="token keyword">return</span> <span class="token punctuation">{</span>selected<span class="token punctuation">}</span><span class="token punctuation">;</span>
|
|
<span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
|
|
<span class="token punctuation">}</span><span class="token punctuation">;</span>
|
|
|
|
_renderItem <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">{</span>item<span class="token punctuation">}</span><span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">(</span>
|
|
<span class="token operator"><</span>MyListItem
|
|
id<span class="token operator">=</span><span class="token punctuation">{</span>item<span class="token punctuation">.</span>id<span class="token punctuation">}</span>
|
|
onPressItem<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>_onPressItem<span class="token punctuation">}</span>
|
|
selected<span class="token operator">=</span><span class="token punctuation">{</span><span class="token operator">!</span><span class="token operator">!</span><span class="token keyword">this</span><span class="token punctuation">.</span>state<span class="token punctuation">.</span>selected<span class="token punctuation">.</span><span class="token keyword">get</span><span class="token punctuation">(</span>item<span class="token punctuation">.</span>id<span class="token punctuation">)</span><span class="token punctuation">}</span>
|
|
title<span class="token operator">=</span><span class="token punctuation">{</span>item<span class="token punctuation">.</span>title<span class="token punctuation">}</span>
|
|
<span class="token operator">/</span><span class="token operator">></span>
|
|
<span class="token punctuation">)</span><span class="token punctuation">;</span>
|
|
|
|
<span class="token function">render</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
|
|
<span class="token keyword">return</span> <span class="token punctuation">(</span>
|
|
<span class="token operator"><</span>FlatList
|
|
data<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>props<span class="token punctuation">.</span>data<span class="token punctuation">}</span>
|
|
extraData<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>state<span class="token punctuation">}</span>
|
|
keyExtractor<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>_keyExtractor<span class="token punctuation">}</span>
|
|
renderItem<span class="token operator">=</span><span class="token punctuation">{</span><span class="token keyword">this</span><span class="token punctuation">.</span>_renderItem<span class="token punctuation">}</span>
|
|
<span class="token operator">/</span><span class="token operator">></span>
|
|
<span class="token punctuation">)</span><span class="token punctuation">;</span>
|
|
<span class="token punctuation">}</span>
|
|
<span class="token punctuation">}</span></div><p>This is a convenience wrapper around <a href="docs/virtualizedlist.html" target="_blank"><code><VirtualizedList></code></a>,
|
|
and thus inherits its props (as well as those of <code>ScrollView</code>) that aren't explicitly listed
|
|
here, along with the following caveats:</p><ul><li>Internal state is not preserved when content scrolls out of the render window. Make sure all
|
|
your data is captured in the item data or external stores like Flux, Redux, or Relay.</li><li>This is a <code>PureComponent</code> which means that it will not re-render if <code>props</code> remain shallow-
|
|
equal. Make sure that everything your <code>renderItem</code> function depends on is passed as a prop
|
|
(e.g. <code>extraData</code>) that is not <code>===</code> after updates, otherwise your UI may not update on
|
|
changes. This includes the <code>data</code> prop and parent component state.</li><li>In order to constrain memory and enable smooth scrolling, content is rendered asynchronously
|
|
offscreen. This means it's possible to scroll faster than the fill rate ands momentarily see
|
|
blank content. This is a tradeoff that can be adjusted to suit the needs of each application,
|
|
and we are working on improving it behind the scenes.</li><li>By default, the list looks for a <code>key</code> prop on each item and uses that for the React key.
|
|
Alternatively, you can provide a custom <code>keyExtractor</code> prop.</li></ul><p>Also inherets <a href="docs/scrollview.html#props" target="_blank">ScrollView Props</a>, unless it is nested in another FlatList of same orientation.</p></div><h3><a class="anchor" name="props"></a>Props <a class="hash-link" href="docs/flatlist.html#props">#</a></h3><div class="props"><div class="prop"><h4 class="propTitle"><a class="anchor" name="numcolumns"></a>numColumns?: <a class="hash-link" href="docs/flatlist.html#numcolumns">#</a></h4></div></div><span><h3><a class="anchor" name="methods"></a>Methods <a class="hash-link" href="docs/flatlist.html#methods">#</a></h3><div class="props"><div class="prop"><h4 class="methodTitle"><a class="anchor" name="scrolltoend"></a>scrollToEnd<span class="methodType">(params?: object)</span> <a class="hash-link" href="docs/flatlist.html#scrolltoend">#</a></h4><div><p>Scrolls to the end of the content. May be janky without <code>getItemLayout</code> prop.</p></div></div><div class="prop"><h4 class="methodTitle"><a class="anchor" name="scrolltoindex"></a>scrollToIndex<span class="methodType">(params: object)</span> <a class="hash-link" href="docs/flatlist.html#scrolltoindex">#</a></h4><div><p>Scrolls to the item at the specified index such that it is positioned in the viewable area
|
|
such that <code>viewPosition</code> 0 places it at the top, 1 at the bottom, and 0.5 centered in the
|
|
middle. <code>viewOffset</code> is a fixed number of pixels to offset the final target position.</p><p>Note: cannot scroll to locations outside the render window without specifying the
|
|
<code>getItemLayout</code> prop.</p></div></div><div class="prop"><h4 class="methodTitle"><a class="anchor" name="scrolltoitem"></a>scrollToItem<span class="methodType">(params: object)</span> <a class="hash-link" href="docs/flatlist.html#scrolltoitem">#</a></h4><div><p>Requires linear scan through data - use <code>scrollToIndex</code> instead if possible.</p><p>Note: cannot scroll to locations outside the render window without specifying the
|
|
<code>getItemLayout</code> prop.</p></div></div><div class="prop"><h4 class="methodTitle"><a class="anchor" name="scrolltooffset"></a>scrollToOffset<span class="methodType">(params: object)</span> <a class="hash-link" href="docs/flatlist.html#scrolltooffset">#</a></h4><div><p>Scroll to a specific content pixel offset in the list.</p><p>Check out <a href="docs/virtualizedlist.html#scrolltooffset" target="_blank">scrollToOffset</a> of VirtualizedList</p></div></div><div class="prop"><h4 class="methodTitle"><a class="anchor" name="recordinteraction"></a>recordInteraction<span class="methodType">()</span> <a class="hash-link" href="docs/flatlist.html#recordinteraction">#</a></h4><div><p>Tells the list an interaction has occured, which should trigger viewability calculations, e.g.
|
|
if <code>waitForInteractions</code> is true and the user has not scrolled. This is typically called by
|
|
taps on items or by navigation actions.</p></div></div><div class="prop"><h4 class="methodTitle"><a class="anchor" name="flashscrollindicators"></a>flashScrollIndicators<span class="methodType">()</span> <a class="hash-link" href="docs/flatlist.html#flashscrollindicators">#</a></h4><div><p>Displays the scroll indicators momentarily.</p></div></div></div></span></div><p class="edit-page-block"><a target="_blank" href="https://github.com/facebook/react-native/blob/master/Libraries/Lists/FlatList.js">Improve this page</a> by sending a pull request!</p><div class="docs-prevnext"><a class="docs-prev" href="docs/drawerlayoutandroid.html#content">← Prev</a><a class="docs-next" href="docs/image.html#content">Next →</a></div></div></section><footer class="nav-footer"><section class="sitemap"><a href="/react-native" class="nav-home"><img src="img/header_logo.png" alt="React Native" width="66" height="58"></a><div><h5><a href="docs/">Docs</a></h5><a href="docs/getting-started.html">Getting Started</a><a href="docs/tutorial.html">Learn the Basics</a><a href="docs/components-and-apis.html">Components and APIs</a><a href="docs/more-resources.html">More Resources</a></div><div><h5><a href="/react-native/support.html">Community</a></h5><a href="/react-native/showcase.html">Who's using React Native?</a><a href="http://www.meetup.com/topics/react-native/" target="_blank">Meetups</a><a href="https://www.facebook.com/groups/react.native.community" target="_blank">Facebook Group</a><a href="https://twitter.com/reactnative" target="_blank">Twitter</a></div><div><h5><a href="/react-native/support.html">Help</a></h5><a href="http://stackoverflow.com/questions/tagged/react-native" target="_blank">Stack Overflow</a><a href="https://discord.gg/0ZcbPKXt5bZjGY5n">Reactiflux Chat</a><a href="/react-native/versions.html" target="_blank">Latest Releases</a><a href="https://react-native.canny.io/feature-requests" target="_blank">Feature Requests</a></div><div><h5>More</h5><a href="/react-native/blog">Blog</a><a href="http://facebook.github.io/react/" target="_blank">React</a><a href="https://github.com/facebook/react-native" target="_blank">GitHub</a><div class="githubButton"><a class="github-button" href="https://github.com/facebook/react-native" data-icon="octicon-star" data-count-href="/facebook/react-native/stargazers" data-count-api="/repos/facebook/react-native#stargazers_count" data-count-aria-label="# stargazers on GitHub" aria-label="Star facebook/react-native on GitHub">Star</a></div></div></section><section class="newsletter"><div id="mc_embed_signup"><form action="//reactnative.us10.list-manage.com/subscribe/post?u=db0dd948e2b729ee62625b1a8&id=47cd41008f" method="post" id="mc-embedded-subscribe-form" name="mc-embedded-subscribe-form" class="validate" target="_blank" novalidate><div id="mc_embed_signup_scroll"><label for="mce-EMAIL"><h5>Get the React Native Newsletter</h5></label><input type="email" value="" name="EMAIL" class="email" id="mce-EMAIL" placeholder="email address" required><div style="position:absolute;left:-5000px;" aria-hidden="true"><input type="text" name="b_db0dd948e2b729ee62625b1a8_47cd41008f" tabindex="-1" value=""></div><div class="clear"><input type="submit" value="Sign up" name="subscribe" id="mc-embedded-subscribe" class="button"></div></div></form></div></section><a href="https://code.facebook.com/projects/" target="_blank" class="fbOpenSource"><img src="img/oss_logo.png" alt="Facebook Open Source" width="170" height="45"></a><section class="copyright">Copyright © 2017 Facebook Inc.</section></footer></div><div id="fb-root"></div><script type="text/javascript" src="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.js"></script><script>
|
|
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
|
|
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
|
|
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
|
|
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
|
|
ga('create', 'UA-41298772-2', 'facebook.github.io');
|
|
ga('send', 'pageview');
|
|
|
|
!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)
|
|
){js=d.createElement(s);js.id=id;js.src="https://platform.twitter.com/widgets.js";
|
|
fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");
|
|
|
|
docsearch({
|
|
apiKey: '2c98749b4a1e588efec53b2acec13025',
|
|
indexName: 'react-native-versions',
|
|
inputSelector: '#algolia-doc-search',
|
|
algoliaOptions: { facetFilters: [ "tags:0.49" ], hitsPerPage: 5 }
|
|
});
|
|
</script><script src="js/scripts.js"></script><script type="text/javascript" src="//s3.amazonaws.com/downloads.mailchimp.com/js/mc-validate.js"></script><script type="text/javascript">(function($) {window.fnames = new Array(); window.ftypes = new Array();fnames[0]='EMAIL';ftypes[0]='email';fnames[1]='FNAME';ftypes[1]='text';fnames[2]='LNAME';ftypes[2]='text';}(jQuery));var $mcj = jQuery.noConflict(true);</script><script type="text/javascript" src="https://snack.expo.io/embed.js"></script><script async defer src="https://buttons.github.io/buttons.js"></script></body></html> |