AMP
ID
English Deutsch Français العربية Español Italiano 日本語 한국어 Português Русский Türkçe 中文 Polski Tiếng việt

amp-font

Deprecated

Description

Trigger and monitor the loading of custom fonts on AMP pages.

 

Required Scripts

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

Supported Layouts

Contoh

amp-font

This component is deprecated and should no longer be used. Instead, use the font-display descriptor to specify how to display a font face dependent on whether and when it is ready.

The amp-font component was AMP's solution to controlling timeouts on font loading. With the wide browser adoption of font-display, this component is no longer necessary. It is here for legacy users. Instead, use the font-display descriptor to specify how to display a font face dependent on whether and when it is ready.

Usage

Historically, the amp-font extension was used for controlling timeouts on font loading. We recommend implementing this functionality with font-display instead.

The amp-font extension allows adding and removing CSS classes from document.documentElement or document.body based on whether a font was loaded or is in error-state.

Example:

<amp-font
  layout="nodisplay"
  font-family="My Font"
  timeout="3000"
  on-error-remove-class="my-font-loading"
  on-error-add-class="my-font-missing"
></amp-font>
<amp-font
  layout="nodisplay"
  font-family="My Other Font"
  timeout="1000"
  on-load-add-class="my-other-font-loaded"
  on-load-remove-class="my-other-font-loading"
></amp-font>

The component observes loading of a font. When the font successfully loads it executes the optional on-load-add-class and on-load-remove-class attributes. If the font loading results in an error or timeout, it runs on-error-remove-class and on-error-add-class. These classes toggle on the documentElement for standalone documents, and on body for documents without a documentElement i.e. inside a ShadowRoot.

Use these classes to guard against displaying a font and get the following results:

  • get a short (e.g. 3000ms) timeout in Safari similar to other browsers
  • implement FOIT where the page renders with no text before the font comes in
  • make the timeout very short and only use a font if it was already cached.

Attributes

font-family

The font family of the custom loaded font.

timeout (optional)

The allowed time in millisecond for the custom font to load. Defaults to 3000 when undefined. When set to 0 the component loads font only if the font is in the cache. If set to an invalid value it defaults back to 3000.

on-load-add-class (optional)

CSS class to add to document root after custom font is available.

on-load-remove-class (optional)

CSS class to remove from document root after custom font is available.

on-error-add-class (optional)

CSS class to add to the document root if the timeout interval runs out before the font is available.

on-error-remove-class (optional)

CSS class to remove from document root if the timeout interval runs out before the font is available.

font-weight (optional)

Behaves same as standard CSS font-weight property.

font-style (optional)

Behaves same as standard CSS font-style property.

font-variant (optional)

Behaves same as standard CSS font-variant property.

layout

The layout attribute must be set to nodisplay.

Validation

See amp-font rules in the AMP validator specification.

Perlu bantuan lainnya?

Anda telah membaca dokumen ini belasan kali, tetapi belum semua pertanyaan Anda terjawab? Mungkin orang lain merasakan hal yang sama. Berinteraksilah dengan mereka di Stack Overflow.

Kunjungi Stack Overflow
Menemukan bug atau ada fitur yang kurang?

Proyek AMP sangat menganjurkan partisipasi dan kontribusi Anda! Kami berharap Anda akan terus ambil bagian dalam komunitas sumber terbuka kami, tetapi kami juga menerima kontribusi satu kali untuk topik tertentu yang Anda minati.

Kunjungi GitHub