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<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Sed voluptates, cupiditate ratione impedit maxime corporis delectus quo consequuntur quis dolorem enim perferendis voluptas sit! Voluptatum soluta corporis harum quam beatae.</p>
<div id="adzone"></div>
<p>Consectetur nam eaque facilis, non consequatur laborum dicta vel autem, omnis unde commodi veniam eligendi quod nostrum quisquam blanditiis dolore? Asperiores odit quasi expedita voluptatum suscipit necessitatibus, amet architecto nemo.</p>
body {
max-width: 300px;
margin: 1rem auto;
}
p {
margin: 1rem 0;
}
#adzone {
max-height: 0;
overflow: hidden;
}
.ad {
background: lightyellow;
padding: 1rem;
p {
margin: 0;
}
img {
display: block;
margin: 0 0 1rem 0;
}
}
.test-height-element {
position: absolute;
top: -9999px;
left: -9999px;
padding: 1rem;
}
// We aren't using this, but if we wanted to go with a mostly-CSS solution, we could apply a class to the ad that used this. It's just not as nice with the magic number in there instead of measuring.
@keyframes slideOpen {
to {
max-height: 500px;
padding: 1rem;
margin: 0 0 1rem 0;
}
}
// This is already in the DOM. It's where we're gonna drop in the ad.
var adZone = document.querySelector("#adzone");
// Dependency-free Ajax library
axios({
method: 'GET',
url: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/3/example-ad.html'
}).then(function(response) {
// Any DOM manipulation we want to do we can do upfront
var adHTML = "<div class='ad'>" + response.data + "</div>";
// The CSS Way (not used in this tutorial)
// adZone.classList.add("loaded");
// We're going to do this mostly in JS
// We need to figure this out!
var ajaxContentHeight = 0;
// We need a dummy element
var testerElement = document.createElement("div");
// That is exactly as wide as were we're putting the ad
testerElement.style.width = adZone.offsetWidth;
// Position it off screen though, nobody needs to see it
testerElement.classList.add("test-height-element");
// Temporarily put the ad in there
testerElement.innerHTML = adHTML;
// Plop it on the page for a sec
document.body.appendChild(testerElement);
// If there are any images in it, we need to wait for them to
// load, otherwise our measuremenets will be off
imagesLoaded(testerElement, function() {
// Now we can measure the height!
ajaxContentHeight = testerElement.offsetHeight + "px";
// Nuke the dummy element
testerElement.remove();
// Drop the ad in the real place
// It's collapsed by default
adZone.innerHTML = adHTML;
// Now apply some styles to allow it to transition
adZone.style.transition = "1s";
adZone.style.maxHeight = ajaxContentHeight;
// After it's done, remove the max height, in case of reflow
setTimeout(function() {
adZone.style.maxHeight = "none";
}, 1001);
});
});
Also see: Tab Triggers