Bootstrap 4 - Scrollspy
Descrizione
Scrollspy viene utilizzato per indicare il collegamento attualmente attivo nel menu, in base alla posizione di scorrimento.
Scrollspy di base
Scrollspy utilizza l'attributo data-spy = "scroll" , che può essere utilizzato come area scorrevole (spesso questo è l'elemento) e aggiunge l' attributo data-target con l'ID o la classe dell'elemento padre di qualsiasi componente Bootstrap .navbar per indicare La barra di navigazione è collegata con l'area scorrevole e i collegamenti di navigazione saranno evidenziati. L' attributo opzionale data-offset definisce il numero di pixel che calcola la posizione dello scorrimento dall'alto.
L'esempio seguente mostra l'utilizzo di scrollspy:
Esempio
<html lang = "en">
<head>
<!-- Meta tags -->
<meta charset = "utf-8">
<meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
<!-- Bootstrap CSS -->
<link rel = "stylesheet"
href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"
integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO"
crossorigin = "anonymous">
<title>Bootstrap 4 Example</title>
<style>
#Scrollspy {
position: relative;
overflow-y: scroll;
height: 300px;
}
#Scrollspynested {
height: 200px;
overflow-y: scroll;
}
#container {
overflow: hidden;
}
</style>
</head>
<body>
<div class = "container-fluid">
<h2>Scrollspy</h2>
<div id = "Scrollspy" data-spy = "scroll" data-target = ".navbar" data-offset = "50">
<nav class = "navbar navbar-expand-sm bg-dark navbar-dark fixed-top">
<ul class = "navbar-nav">
<li class = "nav-item">
<a class = "nav-link" href = "#section1">Section 1</a>
</li>
<li class = "nav-item">
<a class = "nav-link" href = "#section2">Section 2</a>
</li>
<li class = "nav-item">
<a class = "nav-link" href = "#section3">Section 3</a>
</li>
<li class = "nav-item dropdown">
<a class = "nav-link dropdown-toggle" href = "#"
id = "navbardrop" data-toggle = "dropdown">
Section 4
</a>
<div class = "dropdown-menu">
<a class = "dropdown-item" href = "#section41">Link 1</a>
<a class = "dropdown-item" href = "#section42">Link 2</a>
</div>
</li>
</ul>
</nav>
<div id = "section1" class = "container-fluid"
style = "padding-top:70px;padding-bottom:70px">
<h1>This is Section 1</h1>
<p>Cotent for section #1</p>
</div>
<div id = "section2" class = "container-fluid"
style = "padding-top:70px;padding-bottom:70px">
<h1>This is Section 2</h1>
<p>Cotent for section #2</p>
</div>
<div id = "section3" class = "container-fluid"
style = "padding-top:70px;padding-bottom:70px">
<h1>This is Section 3</h1>
<p>Cotent for section #3</p>
</div>
<div id = "section41" class = "container-fluid"
style = "padding-top:70px;padding-bottom:70px">
<h1>This is Section 4 Submenu 1</h1>
<p>Cotent for section #4.1</p>
</div>
<div id = "section42" class = "container-fluid"
style = "padding-top:70px;padding-bottom:70px">
<h1>This is Section 4 Submenu 2</h1>
<p>Cotent for section #4.2</p>
</div>
</div>
</div>
<!-- jQuery library -->
<script src = "https://code.jquery.com/jquery-3.2.1.slim.min.js"
integrity = "sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
crossorigin = "anonymous">
</script>
<!-- Popper -->
<script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"
integrity = "sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
crossorigin = "anonymous">
</script>
<!-- Latest compiled and minified Bootstrap JavaScript -->
<script src = "https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"
integrity = "sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
crossorigin = "anonymous">
</script>
</body>
</html>Produrrà il seguente risultato:
Produzione
Menu verticale Scrollspy
È possibile utilizzare le pillole di navigazione come menu verticale utilizzando scrollspy come mostrato nell'esempio seguente:
Esempio
<html lang = "en">
<head>
<!-- Meta tags -->
<meta charset = "utf-8">
<meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
<!-- Bootstrap CSS -->
<link rel = "stylesheet"
href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"
integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO"
crossorigin = "anonymous">
<title>Bootstrap 4 Example</title>
<style>
body {
position: relative;
}
ul.nav-pills {
top: 50px;
position: fixed;
}
div.col-8 div {
height: 500px;
}
</style>
</head>
<body data-spy = "scroll" data-target = "#myScrollspy" data-offset = "1">
<h2>Scrollspy Vertical Menu</h2>
<div class = "container-fluid">
<div class = "row">
<nav class = "col-sm-3 col-4" id = "myScrollspy">
<ul class = "nav nav-pills flex-column">
<li class = "nav-item">
<a class = "nav-link active" href = "#section1">Section 1</a>
</li>
<li class = "nav-item">
<a class = "nav-link" href = "#section2">Section 2</a>
</li>
<li class = "nav-item dropdown">
<a class = "nav-link dropdown-toggle" data-toggle = "dropdown"
href = "#">Section 3</a>
<div class = "dropdown-menu">
<a class = "dropdown-item" href = "#section31">dropdown-item 1</a>
<a class = "dropdown-item" href = "#section32">dropdown-item 2</a>
</div>
</li>
<li class = "nav-item">
<a class = "nav-link" href = "#section4">Section 4</a>
</li>
</ul>
</nav>
<div class = "col-sm-9 col-8">
<div id = "section1" >
<h1>This is Section 1</h1>
<p>Content for section #1</p>
</div>
<div id = "section2" >
<h1>This is Section 2</h1>
<p>Content for section #2</p>
</div>
<div id = "section31" >
<h1>This is Section 3.1</h1>
<p>Content for section #3.1</p>
</div>
<div id = "section32" >
<h1>This is Section 3.2</h1>
<p>Content for section #3.2</p>
</div>
<div id = "section4" >
<h1>This is Section 4</h1>
<p>Content for section #4</p>
</div>
</div>
</div>
</div>
<!-- jQuery library -->
<script src = "https://code.jquery.com/jquery-3.2.1.slim.min.js"
integrity = "sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
crossorigin = "anonymous">
</script>
<!-- Popper -->
<script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"
integrity = "sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
crossorigin = "anonymous">
</script>
<!-- Latest compiled and minified Bootstrap JavaScript -->
<script src = "https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"
integrity = "sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
crossorigin = "anonymous">
</script>
</body>
</html>Produrrà il seguente risultato: