Sticky Header after scrolling down

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野性不改
野性不改 2020-11-27 11:19

I saw this sticky header on this website: http://dunked.com/ (no longer active, view archived site)

When you scroll down the sticky header comes down from t

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  • 2020-11-27 12:07

    Here's a start. Basically, we copy the header on load, and then check (using .scrollTop() or window.scrollY) to see when the user scrolls beyond a point (e.g. 200pixels). Then we simply toggle a class (in this case .down) which moves the original into view.

    Lastly all we need to do is apply a transition: top 0.2s ease-in to our clone, so that when it's in the .down state it slides into view. Dunked does it better, but with a little playing around it's easy to configure

    CSS

    header {
      position: relative;
      width: 100%;
      height: 60px;
    }
    
    header.clone {
      position: fixed;
      top: -65px;
      left: 0;
      right: 0;
      z-index: 999;
      transition: 0.2s top cubic-bezier(.3,.73,.3,.74);
    }
    
    body.down header.clone {
      top: 0;
    }
    

    either Vanilla JS (polyfill as required)

    var sticky = {
      sticky_after: 200,
      init: function() {
        this.header = document.getElementsByTagName("header")[0];
        this.clone = this.header.cloneNode(true);
        this.clone.classList.add("clone");
        this.header.insertBefore(this.clone);
        this.scroll();
        this.events();
      },
    
      scroll: function() {
        if(window.scrollY > this.sticky_after) {
          document.body.classList.add("down");
        }
        else {
          document.body.classList.remove("down");
        }
      },
    
      events: function() {
        window.addEventListener("scroll", this.scroll.bind(this));
      }
    };
    
    document.addEventListener("DOMContentLoaded", sticky.init.bind(sticky));
    

    or jQuery

    $(document).ready(function() {
      var $header = $("header"),
          $clone = $header.before($header.clone().addClass("clone"));
    
      $(window).on("scroll", function() {
        var fromTop = $("body").scrollTop();
        $('body').toggleClass("down", (fromTop > 200));
      });
    });
    

    Newer Reflections

    Whilst the above answers the OP's original question of "How does Dunked achieve this effect?", I wouldn't recommend this approach. For starters, copying the entire top navigation could be pretty costly, and there's no real reason why we can't use the original (with a little bit of work).

    Furthermore, Paul Irish and others, have written about how animating with translate() is better than animating with top. Not only is it more performant, but it also means that you don't need to know the exact height of your element. The above solution would be modified with the following (See JSFiddle):

    header.clone {
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      transform: translateY(-100%);
      transition: 0.2s transform cubic-bezier(.3,.73,.3,.74);
    }
    
    body.down header.clone {
      transform: translateY(0);
    }
    

    The only drawback with using transforms is, that whilst browser support is pretty good, you'll probably want to add vendor prefixed versions to maximize compatibility.

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  • 2020-11-27 12:07

    window bottom scroll to top scroll using jquery.

     <script> 
    
     var lastScroll = 0;
    
     $(document).ready(function($) {
    
     $(window).scroll(function(){
    
     setTimeout(function() { 
        var scroll = $(window).scrollTop();
        if (scroll > lastScroll) {
    
            $("header").removeClass("menu-sticky");
    
        } 
        if (scroll == 0) {
        $("header").removeClass("menu-sticky");
    
        }
        else if (scroll < lastScroll - 5) {
    
    
            $("header").addClass("menu-sticky");
    
        }
        lastScroll = scroll;
        },0);
        });
       });
     </script>
    
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  • 2020-11-27 12:12

    This was not working for me in Firefox.

    We added a conditional based on whether the code places the overflow at the html level. See Animate scrollTop not working in firefox.

      var $header = $("#header #menu-wrap-left"),
      $clone = $header.before($header.clone().addClass("clone"));
    
      $(window).on("scroll", function() {
        var fromTop = Array(); 
        fromTop["body"] = $("body").scrollTop();
        fromTop["html"] = $("body,html").scrollTop();
    
    if (fromTop["body"]) 
        $('body').toggleClass("down", (fromTop["body"] > 650));
    
    if (fromTop["html"]) 
        $('body,html').toggleClass("down", (fromTop["html"] > 650));
    
      });
    
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  • 2020-11-27 12:16

    I suggest to use sticky js it's have best option ever i have seen. nothing to do just ad this js on you

     https://raw.githubusercontent.com/garand/sticky/master/jquery.sticky.js
    

    and use below code :

    <script>
      $(document).ready(function(){
        $("#sticker").sticky({topSpacing:0});
      });
    </script>
    

    Its git repo: https://github.com/garand/sticky

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