amp-dynamic-css-classes

Introduction

AMP's dynamic CSS classes provided by the amp-dynamic-css-class enable boolean logic for a handful of conditions

Setup

Include the amp-dynamic-css-classes extended component.

<script async custom-element="amp-dynamic-css-classes" src="https://cdn.ampproject.org/v0/amp-dynamic-css-classes-0.1.js"></script>

For the purpose of this sample, we're creating some helper CSS classes that use the CSS rules defined by amp-dynamic-css-classes. These allow us to more succinctly refer to the conditions in our code below.

<style amp-custom>
  :root {
    --space-2: 1rem;   /* 16px */
  }
  body:not(.amp-referrer-pinterest-com) .if-pinterest,
  body:not(.amp-referrer-ampbyexample-com) .if-ampbyexample,
  body:not(.amp-referrer-google-com) .if-google,
  body:not(.amp-referrer-twitter-com) .if-twitter,
  body:not(.amp-referrer-linkedin-com) .if-linkedin,
  body:not(.amp-referrer-localhost) .if-localhost {
    display: none;
  }
  body:not(.amp-viewer) .if-viewer,
  body.amp-viewer .if-not-viewer {
    display: none;
  }
  .dynamic-css {
    padding: var(--space-2);
  }
</style>

Referrer

Using these referrer classes can allow you to conditionally include elements. You do not need to include a call to the amp-dynamic-css-classes component to initialize the classes on the body element.

You were referred here or embedded by Pinterest!

You were referred here or embedded by Twitter!

You were referred here or embedded by Google!

You came here directly! Cool :)

<div class="if-pinterest dynamic-css">You were referred here or embedded by Pinterest!</div>
<div class="if-twitter dynamic-css">You were referred here or embedded by Twitter!</div>
<div class="if-google dynamic-css">You were referred here or embedded by Google!</div>
<div class="if-ampbyexample dynamic-css">You came here directly!  Cool :)</div>
<div class="if-localhost dynamic-css">You came here directly!  Cool :)</div>

Viewer

The 'viewer' classes enable you to style the page based on whether it's embedded inside an AMP viewer. Try it out on the Google AMP Viewer. Note this works only on a mobile device or in your browser's mobile emulation mode.

Hey! You're not visiting within the context of an AMP Viewer!

Ahoy! Since you're coming from a viewer.

<div class="if-not-viewer dynamic-css">Hey! You're not visiting within the context of an AMP Viewer!</div>
<div class="if-viewer dynamic-css">Ahoy! Since you're coming from a viewer.</div>

¿Necesita explicaciones más detalladas?

Si las explicaciones que se encuentran en esta página no responden todas sus preguntas, no dude en comunicarse con otros usuarios de AMP para discutir el caso de uso exacto.

Ir a Stack Overflow

¿Faltó que explicáramos alguna función?

¡El proyecto AMP alienta profundamente su participación y contribuciones! Esperamos que se convierta en un miembro permanente de nuestra comunidad de código abierto, pero también agradecemos las contribuciones esporádicas sobre los temas que le apasionan especialmente.

Editar ejemplo en GitHub

Written by @jmadler