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<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, height=device-height, initial-scale=1, user-scalable=no"> <meta name="description" content="API docs for the List.filled constructor from Class List from the dart:core library, for the Dart programming language."> <title>List.filled constructor - List - dart:core library - Dart API</title> <link rel="canonical" href="https://api.dart.dev/dart-core/List/List.filled.html"> <link rel="preconnect" href="https://fonts.gstatic.com"> <link href="https://fonts.googleapis.com/css2?family=Roboto+Mono:ital,wght@0,300;0,400;0,500;0,700;1,400&display=swap" rel="stylesheet"> <link href="https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@24,400,0,0" rel="stylesheet"> <link rel="stylesheet" href="../../static-assets/github.css?v1"> <link rel="stylesheet" href="../../static-assets/styles.css?v1"> <link rel="icon" href="../../static-assets/favicon.png?v1">  <script async src="https://www.googletagmanager.com/gtag/js?id=G-VVQ8908SJ5"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-VVQ8908SJ5'); </script> <link rel="preconnect" href="https://fonts.googleapis.com"> <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin> <link rel="preload" href="https://fonts.googleapis.com/css2?family=Google+Sans+Text:wght@400&family=Google+Sans:wght@500&display=swap" as="style"> <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Google+Sans+Text:wght@400&family=Google+Sans:wght@500&display=swap"> <link rel="stylesheet" href="https://www.gstatic.com/glue/cookienotificationbar/cookienotificationbar.min.css"> </head> <body data-base-href="../../" data-using-base-href="false" class="light-theme"> <div id="overlay-under-drawer"></div> <header id="title"> <span id="sidenav-left-toggle" class="material-symbols-outlined" role="button" tabindex="0">menu</span> <ol class="breadcrumbs gt-separated dark hidden-xs"> <li><a href="../../index.html">Dart</a></li> <li><a href="../../dart-core">dart:core</a></li> <li><a href="../../dart-core/List-class.html">List<span class="signature"><<wbr><span class="type-parameter">E</span>></span></a></li> <li class="self-crumb">List.filled factory constructor</li> </ol> <div class="self-name">List.filled</div> <form class="search navbar-right" role="search"> <input type="text" id="search-box" autocomplete="off" disabled class="form-control typeahead" placeholder="Loading search..."> </form> <div class="toggle" id="theme-button" title="Toggle brightness"> <label for="theme"> <input type="checkbox" id="theme" value="light-theme"> <span id="dark-theme-button" class="material-symbols-outlined"> dark_mode </span> <span id="light-theme-button" class="material-symbols-outlined"> light_mode </span> </label> </div> </header> <main> <div id="dartdoc-main-content" class="main-content" data-above-sidebar="dart-core/List-class-sidebar.html" data-below-sidebar=""> <div> <div id="external-links" class="btn-group"><a title="View source code" class="source-link" href="https://github.com/dart-lang/sdk/blob/a8bfb132c5f7b9555d13ea79eaf0eaa77825824d/sdk/lib/core/list.dart#L151"><span class="material-symbols-outlined">description</span></a></div> <h1><span class="kind-constructor">List<<wbr><span class="type-parameter">E</span>>.filled</span> constructor </h1></div> <section class="multi-line-signature"> <span class="name ">List<<wbr><span class="type-parameter">E</span>>.filled</span>(<wbr><ol class="parameter-list"> <li><span class="parameter" id="filled-param-length"><span class="type-annotation"><a href="../../dart-core/int-class.html">int</a></span> <span class="parameter-name">length</span>, </span></li> <li><span class="parameter" id="filled-param-fill"><span class="type-annotation">E</span> <span class="parameter-name">fill</span>, {</span></li> <li><span class="parameter" id="filled-param-growable"><span class="type-annotation"><a href="../../dart-core/bool-class.html">bool</a></span> <span class="parameter-name">growable</span> = <span class="default-value">false</span>, </span></li> </ol>}) </section> <section class="desc markdown"> <p>Creates a list of the given length with <code>fill</code> at each position.</p> <p>The <code>length</code> must be a non-negative integer.</p> <p>Example:</p> <pre class="language-dart"><code class="language-dart">final zeroList = List<int>.filled(3, 0, growable: true); // [0, 0, 0] </code></pre> <p>The created list is fixed-length if <code>growable</code> is false (the default) and growable if <code>growable</code> is true. If the list is growable, increasing its <code>length</code> will <em>not</em> initialize new entries with <code>fill</code>. After being created and filled, the list is no different from any other growable or fixed-length list created using <code>[]</code> or other <a href="../../dart-core/List-class.html">List</a> constructors.</p> <p>All elements of the created list share the same <code>fill</code> value.</p> <pre class="language-dart"><code class="language-dart">final shared = List.filled(3, []); shared[0].add(499); print(shared); // [[499], [499], [499]] </code></pre> <p>You can use <a href="../../dart-core/List/List.generate.html">List.generate</a> to create a list with a fixed length and a new object at each position.</p> <pre class="language-dart"><code class="language-dart">final unique = List.generate(3, (_) => []); unique[0].add(499); print(unique); // [[499], [], []] </code></pre> </section> <section class="summary source-code" id="source"> <h2><span>Implementation</span></h2> <pre class="language-dart"><code class="language-dart">external factory List.filled(int length, E fill, {bool growable = false});</code></pre> </section> </div>  <div id="dartdoc-sidebar-left" class="sidebar sidebar-offcanvas-left">  <header id="header-search-sidebar" class="hidden-l"> <form class="search-sidebar" role="search"> <input type="text" id="search-sidebar" autocomplete="off" disabled class="form-control typeahead" placeholder="Loading search..."> </form> </header> <ol class="breadcrumbs gt-separated dark hidden-l" id="sidebar-nav"> <li><a href="../../index.html">Dart</a></li> <li><a href="../../dart-core">dart:core</a></li> <li><a href="../../dart-core/List-class.html">List<span class="signature"><<wbr><span class="type-parameter">E</span>></span></a></li> <li class="self-crumb">List.filled factory constructor</li> </ol> <h5>List class</h5> <div id="dartdoc-sidebar-left-content"></div> </div> <div id="dartdoc-sidebar-right" class="sidebar sidebar-offcanvas-right"> </div> </main> <footer> <span class="no-break"> Dart 3.7.0 </span> <span class="glue-footer"> <span class="no-break"> | <a href="https://dart.dev/terms" title="Terms of use">Terms</a> </span> <span class="no-break"> | <a href="https://policies.google.com/privacy" target="_blank" rel="noopener" title="Privacy policy" class="no-automatic-external">Privacy</a> </span> <span class="no-break"> | <a href="https://dart.dev/security" title="Security philosophy and practices">Security</a> </span> <div class="copyright" style="font-size: 0.9em; color: darkgrey; margin-top: 0.5em;"> Except as otherwise noted, this site is licensed under a <a style="color: darkgrey;" href="https://creativecommons.org/licenses/by/4.0/"> Creative Commons Attribution 4.0 International License</a> and code samples are licensed under the <a style="color: darkgrey;" href="https://opensource.org/licenses/BSD-3-Clause" class="no-automatic-external"> 3-Clause BSD License</a> </div> </span> </footer> <script src="../../static-assets/highlight.pack.js?v1"></script> <script src="../../static-assets/docs.dart.js"></script> <button aria-hidden="true" class="glue-footer__link glue-cookie-notification-bar-control"> Cookies management controls </button> <script src="https://www.gstatic.com/glue/cookienotificationbar/cookienotificationbar.min.js" data-glue-cookie-notification-bar-category="2B"> </script> </body> </html>