How to make the (fixed) content hide and show after rest content is scrolled-CodePudding

<style>
    div{
        height: 100%;
    }
    p{
        background-color: aqua;
        position: fixed;
        bottom: 0;
    }
</style>

<html>
  <head>
    <body>

        <div>
            <h1>hello</h1>
            <img src="image.jpeg" alt="">
        </div>
        <p>Lorem ipsum dolor, sit amet consectetur adipisicing elit.
             endis iusto eligendi rem solutaaborummaxime?     
        </p>
    </body>
  </head>
</html>

Hello, I want the fixed bottom content to be visible after all the upper contents are scrolled using html and css only if possible or by using js.

CodePudding user response：

What I take from this is that you want the content to only be shown when the user has scrolled all the way down. You can simply do this by removing the position: fixed;, since that makes the paragraph visible at all times, even when the user is still scrolling.

CodePudding user response：

You can use JavaScript, the difference between total height and scrolling top position equal the page height indicates the page end is reached.

window.addEventListener("scroll", function(event) {
  let footer = document.querySelector(".footer");
  if (
    document.body.getBoundingClientRect().height - window.scrollY <
    window.innerHeight
  ) {
    footer.style.display = "block";
  } else {
    footer.style.display = "none";
  }
});

#box {
  height: 100%;
}

p {
  background-color: aqua;
  position: fixed;
  bottom: 0;
  display: none;
}

<div id='box'>
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    repetition, injected humour, or non-characteristic words etc.</h1>
  <img src="image.jpeg" alt="">
</div>
<p class='footer'>Lorem ipsum dolor, sit amet consectetur adipisicing elit. endis iusto eligendi rem solutaaborummaxime?
</p>

CodePudding user response：

You can take a look at IntersectionObserver. It will allow avoid scroll listener. If there's an element which(e.g. it is on/off the viewport) can be a trigger for hide/show, intersection will help