在页脚处停止固定位置

Question

我正在寻找解决在页面页脚停止固定对象的流行问题的解决方案.

我基本上在屏幕的左下角有一个固定的"共享"框,我不希望它滚动页脚,所以我需要它停10px在页脚上方.

我在这里看到了其他问题以及其他问题.我能找到的最近/最简单的演示是http://jsfiddle.net/bryanjamesross/VtPcm/,但我无法让它与我的情况一起工作.

这是共享框的html:

    <div id="social-float">
        <div class="sf-twitter">
            ...
        </div>

        <div class="sf-facebook">
            ...
        </div>

        <div class="sf-plusone">
            ...
        </div>
    </div>

......和CSS:

#social-float{
position: fixed;
bottom: 10px;
left: 10px;
width: 55px;
padding: 10px 5px;
text-align: center;
background-color: #fff;
border: 5px solid #ccd0d5;
-webkit-border-radius: 2px;
-moz-border-radius: 2px;
border-radius: 2px;
display: none;
}

页脚是#footer,它没有固定的高度,如果这有任何区别.

如果有人可以帮助我为此创建一个简单的jQuery解决方案,我会非常感激!

Answer 1

现场演示

首先,每次滚动页面时检查其偏移量

$(document).scroll(function() {
    checkOffset();
});

如果它在页脚之前被击倒在10px以下,则使其位置绝对.

function checkOffset() {
    if($('#social-float').offset().top + $('#social-float').height() 
                                           >= $('#footer').offset().top - 10)
        $('#social-float').css('position', 'absolute');
    if($(document).scrollTop() + window.innerHeight < $('#footer').offset().top)
        $('#social-float').css('position', 'fixed'); // restore when you scroll up
}

请注意,#social-float父母应该是页脚的兄弟

<div class="social-float-parent">
    <div id="social-float">
        something...
    </div>
</div>
<div id="footer">
</div>

祝好运 :)

Answer 2

我刚刚在我正在研究的网站上解决了这个问题,并且认为我会分享它,希望它可以帮助某人.

我的解决方案是从页脚到页面顶部的距离 - 如果用户滚动得比这更远,它会以负边距拉回侧边栏.

$(window).scroll(() => { 
  // Distance from top of document to top of footer.
  topOfFooter = $('#footer').position().top;
  // Distance user has scrolled from top, adjusted to take in height of sidebar (570 pixels inc. padding).
  scrollDistanceFromTopOfDoc = $(document).scrollTop() + 570;
  // Difference between the two.
  scrollDistanceFromTopOfFooter = scrollDistanceFromTopOfDoc - topOfFooter;

  // If user has scrolled further than footer,
  // pull sidebar up using a negative margin.
  if (scrollDistanceFromTopOfDoc > topOfFooter) {
    $('#cart').css('margin-top',  0 - scrollDistanceFromTopOfFooter);
  } else  {
    $('#cart').css('margin-top', 0);
  }
});

Answer 3

这是@Sang解决方案，但没有Jquery。

var socialFloat = document.querySelector('#social-float');
var footer = document.querySelector('#footer');

function checkOffset() {
  function getRectTop(el){
    var rect = el.getBoundingClientRect();
    return rect.top;
  }
  
  if((getRectTop(socialFloat) + document.body.scrollTop) + socialFloat.offsetHeight >= (getRectTop(footer) + document.body.scrollTop) - 10)
    socialFloat.style.position = 'absolute';
  if(document.body.scrollTop + window.innerHeight < (getRectTop(footer) + document.body.scrollTop))
    socialFloat.style.position = 'fixed'; // restore when you scroll up
  
  socialFloat.innerHTML = document.body.scrollTop + window.innerHeight;
}

document.addEventListener("scroll", function(){
  checkOffset();
});

div.social-float-parent { width: 100%; height: 1000px; background: #f8f8f8; position: relative; }
div#social-float { width: 200px; position: fixed; bottom: 10px; background: #777; }
div#footer { width: 100%; height: 200px; background: #eee; }

<div class="social-float-parent">
    <div id="social-float">
        float...
    </div>
</div>
<div id="footer">
</div>

Answer 4

现在可以用 来完成position: sticky。

body,
html {
  height: 100%;
}

body {
  background-color: linen;
  margin: 0;
}


body,
main {
  display: flex;
  flex-direction: column;
}

main,
section {
  flex: 1;
}

main {
  min-height: 200vh;
}

.sticky {
  position: sticky;
  top: 0;
  background-color: lightcoral;
  padding: 1rem;
}

p {
  padding: 0 1rem;
}

footer {
  background-color: lightblue;
  padding: 15rem 1rem;
}

<main>
  <section>
    <div class="sticky">
      <h2>I am sticky<h2>
    </div>
      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer nec odio. Praesent libero. Sed cursus ante dapibus diam. Sed nisi. Nulla quis sem at nibh elementum imperdiet. Duis sagittis ipsum. Praesent mauris. Fusce nec tellus sed augue semper porta. Mauris massa. Vestibulum lacinia arcu eget nulla. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. </p>

  <p>Curabitur sodales ligula in libero. Sed dignissim lacinia nunc. Curabitur tortor. Pellentesque nibh. Aenean quam. In scelerisque sem at dolor. Maecenas mattis. Sed convallis tristique sem. Proin ut ligula vel nunc egestas porttitor. Morbi lectus risus, iaculis vel, suscipit quis, luctus non, massa. Fusce ac turpis quis ligula lacinia aliquet. Mauris ipsum. Nulla metus metus, ullamcorper vel, tincidunt sed, euismod in, nibh. Quisque volutpat condimentum velit. </p>

  <p>Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Nam nec ante. Sed lacinia, urna non tincidunt mattis, tortor neque adipiscing diam, a cursus ipsum ante quis turpis. Nulla facilisi. Ut fringilla. Suspendisse potenti. Nunc feugiat mi a tellus consequat imperdiet. Vestibulum sapien. Proin quam. Etiam ultrices. Suspendisse in justo eu magna luctus suscipit. Sed lectus. Integer euismod lacus luctus magna. Quisque cursus, metus vitae pharetra auctor, sem massa mattis sem, at interdum magna augue eget diam. </p>

  <p>Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi lacinia molestie dui. Praesent blandit dolor. Sed non quam. In vel mi sit amet augue congue elementum. Morbi in ipsum sit amet pede facilisis laoreet. Donec lacus nunc, viverra nec, blandit vel, egestas et, augue. Vestibulum tincidunt malesuada tellus. Ut ultrices ultrices enim. Curabitur sit amet mauris. Morbi in dui quis est pulvinar ullamcorper. Nulla facilisi. Integer lacinia sollicitudin massa. </p>

  <p>Cras metus. Sed aliquet risus a tortor. Integer id quam. Morbi mi. Quisque nisl felis, venenatis tristique, dignissim in, ultrices sit amet, augue. Proin sodales libero eget ante. Nulla quam. Aenean laoreet. Vestibulum nisi lectus, commodo ac, facilisis ac, ultricies eu, pede. Ut orci risus, accumsan porttitor, cursus quis, aliquet eget, justo. Sed pretium blandit orci. Ut eu diam at pede suscipit sodales. Aenean lectus elit, fermentum non, convallis id, sagittis at, neque. Nullam mauris orci, aliquet et, iaculis et, viverra vitae, ligula. </p>
  </section>
  <footer>
    <h2>I am a footer<h2>
  </footer>
</main>