Show footer when user scrolls to the bottom of the page

Question

Here is my footer code.

<div class="row">
    <div class="col-md-12">
        <div> the part that always showing at the bottom  </div>
    </div>
    <div class="col-md-12">
        <div> show only if the user reaching the bottom of the page </div>
    </div>
</div>

My problem is I want my footer stick to the bottom of the page until the user reach the bottom, then show the other content.

Answer 1

With only the help of CSS, you can reconsider it as two footers, one popping, another boring ;)

[id^=foo]{
  background:orange;
  padding:5px;
  font-size:25px;
}

#foo-boring{
  position:fixed;
  bottom:0;
  right:0;
  left:0;
}
#foo-pop{
  position:absolute;
  height:70px;
  right:0; left:0;
}

<div>SCROLL ME DOWN<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br>much contents there.<br> END.</div>
<div id="foo-pop"><b>POP!1!!!1!!1!11!</b></div>
<div id="foo-boring">The boring footer.</div>