zeyev/presentazione
1
0
Fork 0
forked from campiaperti/infra
Code Releases Activity

add note about lazy loading iframes #1672 #1938

Browse source
This commit is contained in:
Hakim El Hattab 2018-10-09 11:08:09 +02:00 committed by GitHub
parent 7b707696b4
commit 62cd74a890
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 7 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
README.md
View file

@ -517,7 +517,7 @@ If there's some part of your content that needs to remain accessible to touch ev
When working on presentation with a lot of media or iframe content it's important to load lazily. Lazy loading means that reveal.js will only load content for the few slides nearest to the current slide. The number of slides that are preloaded is determined by the `viewDistance` configuration option. When working on presentation with a lot of media or iframe content it's important to load lazily. Lazy loading means that reveal.js will only load content for the few slides nearest to the current slide. The number of slides that are preloaded is determined by the `viewDistance` configuration option.
To enable lazy loading all you need to do is change your `src` attributes to `data-src` as shown below. This is supported for image, video, audio and iframe elements. Lazy loaded iframes will also unload when the containing slide is no longer visible. To enable lazy loading all you need to do is change your `src` attributes to `data-src` as shown below. This is supported for image, video, audio and iframe elements.
```html ```html
<section> <section>
@ -530,6 +530,12 @@ To enable lazy loading all you need to do is change your `src` attributes to `da
</section> </section>
``` ```
#### Lazy Loading Iframes
Note that lazy loaded iframes ignore the `viewDistance` configuration and will only load when their containing slide becomes visible. Iframes are also unloaded as soon as the slide is hidden.
When we lazy load a video or audio element, reveal.js won't start playing that content until the slide becomes visible. However there is no way to control this for an iframe since that could contain any kind of content. That means if we loaded an iframe before the slide is visible on screen it could begin playing media and sound in the background.
### API ### API
The `Reveal` object exposes a JavaScript API for controlling navigation and reading state: The `Reveal` object exposes a JavaScript API for controlling navigation and reading state: