Компьютерапия

Плагин Scrollspy (auto update nav) позволяет вам настраивать разделы страницы в зависимости от положения прокрутки. В своей базовой реализации при прокрутке вы можете добавлять активные классы в навигационную панель на основе положения прокрутки.

Если вы хотите включить эту функциональность плагина индивидуально, вам понадобится scrollspy.js, после включения bootstrap.js или bootstrap.min.js.

Применение Scrollspy

Вы можете добавить поведение scrollspy в свою навигацию по topbar -

• Через атрибуты данных - добавьте data-spy = "scroll" к элементу, который вы хотите отслеживать. Затем добавьте атрибут data target с идентификатором или классом родительского элемента любого компонента Bootstrap .nav. Чтобы это сработало, у вас должны быть элементы в теле страницы с соответствующими идентификаторами ссылок, на которые вы следите.

  
  <body data-spy = "scroll" data-target = ".navbar-example">
     ...
     <div class = "navbar-example">
        <ul class = "nav nav-tabs">
           ...
        </ul>
     </div>
     ...
  </body>
  

• С помощью JavaScript - Вы можете вызвать scrollspy с JavaScript вместо использования атрибутов данных, выбрав элемент шпионить, а затем вызова .scrollspy() функцию -

  
  $('body').scrollspy({ target: '.navbar-example' })
  

Пример Scrollspy

В следующем примере показано использование плагина scrollspy через атрибуты данных -

<nav id = "navbar-example" class = "navbar navbar-default navbar-static" role = "navigation">
  
   <div class = "navbar-header">
      <button class = "navbar-toggle" type = "button" data-toggle = "collapse"
         data-target = ".bs-js-navbar-scrollspy">
         <span class = "sr-only">Toggle navigation</span>
         <span class = "icon-bar"></span>
         <span class = "icon-bar"></span>
         <span class = "icon-bar"></span>
      </button>
                       
      <a class = "navbar-brand" href = "#">Tutorial Name</a>
   </div>
  
   <div class = "collapse navbar-collapse bs-js-navbar-scrollspy">
      <ul class = "nav navbar-nav">
         <li><a href = "#ios">iOS</a></li>
         <li><a href = "#svn">SVN</a></li>
        
         <li class = "dropdown">
            <a href = "#" id = "navbarDrop2" class = "dropdown-toggle" data-toggle = "dropdown">
               Java
               <b class = "caret"></b>
            </a>
           
            <ul class = "dropdown-menu" role = "menu" aria-labelledby = "navbarDrop2">
               <li><a href = "#jmeter" tabindex = "-1">jmeter</a></li>
               <li><a href = "#ejb" tabindex = "-1">ejb</a></li>
              
               <li class = "divider"></li>
               <li><a href = "#spring" tabindex = "-1">spring</a></li>
            </ul>
           
         </li>
      </ul>
   </div>
  
</nav>
 
<div data-spy = "scroll" data-target = "#navbar-example" data-offset = "0"
   style = "height:200px; overflow:auto; position: relative;">
   <h4 id = "ios">iOS</h4>
           
   <p>iOS is a mobile operating system developed and distributed by Apple
      Inc. Originally released in 2007 for the iPhone, iPod Touch, and Apple
      TV. iOS is derived from OS X, with which it shares the Darwin
      foundation. iOS is Apple's mobile version of the OS X operating system
      used on Apple computers.</p>
  
   <h4 id = "svn">SVN</h4>
  
   <p>Apache Subversion which is often abbreviated as SVN, is a software
      versioning and revision control system distributed under an open source
      license. Subversion was created by CollabNet Inc. in 2000, but now it
      is developed as a project of the Apache Software Foundation, and as
      such is part of a rich community of developers and users.</p>
  
   <h4 id = "jmeter1">jMeter</h4>
  
   <p>jMeter is an Open Source testing software. It is 100% pure Java
      application for load and performance testing.</p>
  
   <h4 id = "ejb">EJB</h4>
  
   <p>Enterprise Java Beans (EJB) is a development architecture for building
      highly scalable and robust enterprise level applications to be deployed
      on J2EE compliant Application Server such as JBOSS, Web Logic etc.</p>
  
   <h4 id = "spring">Spring</h4>
  
   <p>Spring framework is an open source Java platform that provides
      comprehensive infrastructure support for developing robust Java
      applications very easily and very rapidly.</p>
  
   <p>Spring framework was initially written by Rod Johnson and was first
      released under the Apache 2.0 license in June 2003.</p>
  
</div>

Опции Scrollspy

Параметры могут передаваться через атрибуты данных или JavaScript. В следующих таблицах перечислены варианты -

Методы Scrollspy

.scrollspy ('refresh') - При вызове scrollspy с помощью метода JavaScript вам необходимо вызвать метод .refresh для обновления DOM. Это полезно, если любые элементы DOM изменились, т.е. если вы добавили или удалили некоторые элементы. Следующим будет синтаксис использования этого метода.

$('[data-spy = "scroll"]').each(function () {
   var $spy = $(this).scrollspy('refresh')
})

Следующий пример демонстрирует использование метода .scrollspy('refresh') -

<nav id = "myScrollspy" class = "navbar navbar-default navbar-static" role = "navigation">
  
   <div class = "navbar-header">
      <button class = "navbar-toggle" type = "button" data-toggle = "collapse"
         data-target = ".bs-js-navbar-scrollspy">
         <span class = "sr-only">Toggle navigation</span>
         <span class = "icon-bar"></span>
         <span class = "icon-bar"></span>
         <span class = "icon-bar"></span>
      </button>
                       
      <a class = "navbar-brand" href = "#">Tutorial Name</a>
   </div>
  
   <div class = "collapse navbar-collapse bs-js-navbar-scrollspy">
      <ul class = "nav navbar-nav">
         <li class = "active"><a href = "#ios1">iOS</a></li>
         <li><a href = "#svn1">SVN</a></li>
        
         <li class = "dropdown">
            <a href = "#" id = "navbarDrop1" class = "dropdown-toggle" data-toggle  = "dropdown">
               Java
               <b class = "caret"></b>
            </a>
           
            <ul class = "dropdown-menu" role = "menu" aria-labelledby = "navbarDrop1">
               <li><a href = "#jmeter1" tabindex = "-1">jmeter</a></li>
               <li><a href = "#ejb1" tabindex = "-1">ejb</a></li>
              
               <li class = "divider"></li>
               <li><a href = "#spring1" tabindex = "-1">spring</a></li>
            </ul>
           
         </li>
      </ul>
   </div>
  
</nav>
 
<div data-spy = "scroll" data-target = "#myScrollspy" data-offset = "0" 
   style = "height:200px; overflow:auto; position: relative;">
  
   <div class = "section">
      <h4 id = "ios1">iOS<small><a href = "#" onclick = "removeSection(this);">
         &times; Remove this section</a></small>
      </h4>
     
      <p>iOS is a mobile operating system developed and distributed by
         Apple Inc. Originally released in 2007 for the iPhone, iPod Touch, and
         Apple TV. iOS is derived from OS X, with which it shares the Darwin
         foundation. iOS is Apple's mobile version of the OS X operating system
         used on Apple computers.</p>
   </div>
  
   <div class = "section">
      <h4 id = "svn1">SVN<small></small></h4>
      <p>Apache Subversion which is often abbreviated as SVN, is a software
         versioning and revision control system distributed under an open source
         license. Subversion was created by CollabNet Inc. in 2000, but
         now it is developed as a project of the Apache Software Foundation,
         and as such is part of a rich community of developers and users.</p>
   </div>
  
   <div class = "section">
      <h4 id = "jmeter">jMeter<small><a href = "#" onclick = "removeSection(this);">
         &times; Remove this section</a></small>
      </h4>
     
      <p>jMeter is an Open Source testing software. It is 100% pure Java
         application for load and performance testing.</p>
   </div>
  
   <div class = "section">
      <h4 id = "ejb1">EJB</h4>
     
      <p>Enterprise Java Beans (EJB) is a development architecture for
         building highly scalable and robust enterprise level applications
         to be deployed on J2EE compliant Application Server such as
         JBOSS, Web Logic etc.</p>
   </div>
           
   <div class = "section">
      <h4 id = "spring1">Spring</h4>
     
      <p>Spring framework is an open source Java platform that provides
         comprehensive infrastructure support for developing robust Java
         applications very easily and very rapidly.</p>
     
      <p>Spring framework was initially written by Rod Johnson and was first
         released under the Apache 2.0 license in June 2003.</p>
   </div>
  
</div>
 
<script type = "text/javascript">
   $(function(){
      removeSection = function(e) {
         $(e).parents(".section").remove();
        
         $('[data-spy = "scroll"]').each(function () {
            var $spy = $(this).scrollspy('refresh')
         });
      }
      $("#myScrollspy").scrollspy();
   });
</script>

События в Scrollspy

В следующей таблице перечислены события для работы с scrollspy. Это событие может использоваться для подключения к функции.

$("#myScrollspy").on("activate.bs.scrollspy", function(){
   // do something…
})

В следующем примере показано использование события activate.bs.scrollspy -

<html>
   <head>
      <link rel = "stylesheet" href = "bootstrap/css/bootstrap.min.css">
      <script src = "bootstrap/scripts/jquery.min.js"></script>
      <script src = "bootstrap/js/bootstrap.min.js"></script>
     
      <script>
         $(document).ready(function(){
            removeSection = function(e) {
               $(e).parents(".subject").remove();
           
               $('[data-spy="scroll"]').each(function () {
                  var $spy = $(this).scrollspy('refresh')
               });
            }
        
            $("#Navexample").scrollspy();
        
            // The event is fired when an item gets actived with the scrollspy
            $("#Navexample").on('activate.bs.scrollspy', function () {
               var currentSection = $(".nav li.active > a").text();
               $("#spyevent").html("Current Item being viewed >> " + currentSection);
            })
                                                
         });
      </script>
  
      <style>
         .scroll-box {
            height: 250px;
            position: relative;
            overflow: auto;
            font-size:2em;
         }
      </style>
     
   </head>
  
   <body>
      <div class = "container">
         <nav id = "Navexample" class = "navbar navbar-default" role = "navigation">
     
            <!-- Nav Bar -->
            <div class = "navbar-header">
               <button type = "button" class = "navbar-toggle"
                  data-toggle = "collapse" data-target = "#navbarCollapse">
              
                  <span class = "sr-only">Toggle navigation</span>
                  <span class = "icon-bar"></span>
                  <span class = "icon-bar"></span>
                  <span class = "icon-bar"></span>
               </button>
                                                            
               <a class = "navbar-brand" href = "#">Tutorials Point</a>
            </div>
           
            <!-- Links and Sublinks -->
            <div class = "collapse navbar-collapse" id = "navbarCollapse">
               <ul class = "nav navbar-nav">
                  <li class = "active"><a href = "#subject-1">Subject 1</a></li>
                  <li><a href = "#subject-2">Subject 2</a></li>
               
                  <li class = "dropdown"><a href = "#" class = "dropdown-toggle"
                     data-toggle = "dropdown">Subject 3<b class = "caret"></b></a>
                    
                     <ul class = "dropdown-menu">
                        <li><a href = "#subject-3-1">Subject 3.1</a></li>
                        <li><a href = "#subject-3-2">Subject 3.2</a></li>
                        <li><a href = "#subject-3-3">Subject 3.3</a></li>
                     </ul>
                     
                  </li>
                                                                        
                  <li><a href = "#subject-4">Subject 4</a></li>
               </ul>
            </div>
           
         </nav>
        
         <div class = "scroll-box" data-spy = "scroll" data-offset = "0">
            <div class = "subject">
           
               <h3 id = "subject-1">Subject 1
                  <small><a href = "#" onclick = "removeSubject(this);">Remove Subject ×</a></small>
               </h3>
           
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
                                                
            <hr>
        
            <div class = "subject">
               <h3 id = "subject-2">Subject 2
                  <small><a href = "#" onclick = "removeSubject(this);">Remove Subject ×</a></small>
               </h3>
           
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
                                                
            <hr>
        
            <div class = "subject">
               <h3 id = "subject-3">Subject 3
                  <small><a href = "#" onclick = "removeSubject(this);"> Remove Subject ×</a></small>
               </h3>
           
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p><
            </div>
                                                
            <hr>
           
            <div class = "subject">
               <h4 id = "subject-3-1">Subject 3.1
                  <small><a href = "#" onclick = "removeSubject(this);"> Remove Subject ×</a></small>
               </h4>
              
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
           
            <div class = "subject">
               <h4 id = "subject-3-2">Subject 3.2
                  <small><a href = "#" onclick = "removeSubject(this);"> Remove Subject ×</a></small>
               </h4>
              
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
           
            <div class = "subject">
               <h4 id = "subject-3-3">Subject 3.3
                  <small><a href = "#" onclick = "removeSubject(this);">Remove Subject ×</a></small>
               </h4>
              
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
                                                
            <hr>
           
            <div class = "subject">
               <h3 id = "subject-4">Subject 4
                  <small><a href = "#" onclick = "removeSubject(this);">Remove Subject ×</a></small>
               </h3>
              
               <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
                  sed do eiusmod tempor incididunt ut labore et dolore magna
                  aliqua. Ut enim ad minim veniam, quis nostrud exercitation
                  ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
            </div>
           
         </div>
         <hr>
        
         <h4 id = "spyevent" class = "text-info"></h4>
      </div>
     
   </body>
</html>