EnglishEspañol한국어Tiếng ViệtIn this tutorial, we’ll learn how to create a pattern seen on many websites these days: a fixed header which animates to a less obtrusive state as we scroll down the page, We’ll start with the basic structure, then get things working using CSS and pure JavaScript" /> EnglishEspañol한국어Tiếng ViệtIn this tutorial, we’ll learn how to create a pattern seen on many websites these days: a fixed header which animates to a less obtrusive state as we scroll down the page, We’ll start with the basic structure, then get things working using CSS and pure JavaScript" />

Cố định header khi cuộn trang

Difficulty:BeginnerLength:MediumLanguages:url-selector#selectionChanged" data-controller="url-selector">EnglishEspañol한국어Tiếng Việt

In this tutorial, we’ll learn how to create a pattern seen on many websites these days: a fixed header which animates khổng lồ a less obtrusive state as we scroll down the page. We’ll start with the basic structure, then get things working using CSS & pure JavaScript. Before closing, we’ll briefly cover how we can optimize our code as well as discussing challenges present when applying this kind of pattern to touch devices.quý khách vẫn xem: Cố định header khi cuộn trang

To get an idea of what we’re going to build, here’s the kiểm tra (you may prefer fullscreen view):

HTML Markup

We’ll start this exercise with the following markup–a header, containing a và a couple of other nested elements:

Logo ☰ The nav element, which is part of the header, contains three elements; the hình ảnh, the main menu, và a placeholder button khổng lồ trigger a responsive thực đơn (below 1061px). 

Note: If you click on this button, nothing much will happen. Creating the responsive menu is beyond the scope of this tutorial.

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Initial CSS Styles

Now let’s have sầu a look at some CSS styles to lớn get things moving:

header position: fixed; top: 0; width: 100%; padding: 20px; box-sizing: border-box; background: #DD3543;nav display: flex; align-items: flex-end; justify-content: space-between; transition: align-items .2s;.biệu tượng công ty font-size: 2rem; display: inline-block; padding: 20px 30px; background: #F35B66; color: #fff; margin: 50px 0 0 50px; transition: all .2s;ul display: flex; margin: 50px 50px 0 0; padding: 0; transition: margin .2s;li:not(:last-child) margin-right: 20px;li a display: block; padding: 10px 20px;.toggle-thực đơn display: none; font-size: 2rem; color: #fff; margin: 10px 10px 0 0; transition: margin .2s;main display: block; padding: 0 20px;Here’s a brief explanation of the most important rules here:

The header element is a fixed positioned element.We use flexbox lớn layout the nav element.The logo sản phẩm has margin-top: 50px & margin-left: 50px. Additionally, we give it padding: 20px 30px.The main thực đơn mirrors the hình ảnh sản phẩm, with margin-top: 50px and margin-right: 50px.The responsive sầu liên kết button is hidden. It becomes visible when the viewport width is less than 1061px. Moreover, we phối its top & right margins to 10px.We add the transition property to lớn the elements whose property values will change in the future. In this way, we achieve sầu a smooth transition effect between the initial state & the final state. 

With these rules in place, the header looks like this:


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Animating the Header

So far we’ve sầu built the basic structure of our header. It’s now time lớn discuss the next steps:

The main element should be positioned right underneath the header. Remember that the header has positioned: fixed, và it’s therefore positioned on top of the main element. The header should be animated as we scroll down the page.

To solve the first task, we add a padding-top property khổng lồ the main element. The value of this property should be equal khổng lồ the header’s height. In our case, we haven’t specified a fixed height for our header, so we’ll use some JavaScript lớn calculate it, and then add the corresponding padding khổng lồ the main element. 

To solve sầu the second task, we’ll bởi vì the following:

Retrieve sầu the number of pixels that the document has already been scrolled vertically.If this number is greater than 150px, we assign the scroll class to the header.

JavaScript

Here’s the required JavaScript code–we begin by defining some variables, calculating the height of the header, then adding that value as padding-top khổng lồ the main element:

Now onlớn the scrolling event:

function onScroll() window.addEventListener("scroll", callbackFunc); function callbackFunc() var y = window.pageYOffset; if (y > 150) h.classList.add("scroll"); else h.classList.remove("scroll"); Here we take advantage of the window’s pageYOffset property to lớn calculate the number of pixels that our document has been scrolled vertically. chú ý that this property doesn’t work in older versions of IE (here.

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Then we use the classList property khổng lồ add & remove sầu the scroll class from our header. Not all browsers tư vấn this property however, so if you want lớn support any of these you may want to look at the classList.js và classie.js polyfills. For this example, we could have sầu used the className property to lớn manipulate our single class, but in a real-world scenario this might not the ikhuyến mãi solution (in case we have sầu multiple classes). 

To wrap things up, we điện thoại tư vấn our functions in two different cases:

When the page loadsvà as we rekích thước the browser window.

window.onload = function() setTopPadding(); onScroll();;window.onresize = function() setTopPadding();;

CSS

As long as our scrolling exceeds the limit of 150px, a few additional CSS rules take place:

.scroll box-shadow: 0 7px 0 0 rgba(0, 0, 0, .1);.scroll .logo sản phẩm padding: 10px 20px; font-size: 1.5rem;.scroll nav align-items: center;.scroll .biểu tượng logo,.scroll ul,.scroll .toggle-thực đơn margin: 0;Specifically, we make the following changes:

Add a light gray box shadow lớn the header.Reduce the logo’s padding và phông kích cỡ.Change the alignment for the flex items across the cross-axis.Remove the margin from the hình ảnh sản phẩm, the menu, & the responsive links button.

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The aforementioned rules result in this new header layout:


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Going Responsive

As we’ve mentioned in a previous section, when the viewport width is less than 1061px, we hide the thực đơn & show the responsive sầu links button (which doesn’t actually vị anything). Plus, we make a few other changes in the target elements.