iframe background preload behavior now matches inline iframes + adheres to the new 'preloadIframes' config option

This commit is contained in:
Hakim El Hattab 2019-05-13 10:55:29 +02:00
parent a16b71a981
commit 1766e37a63
3 changed files with 130 additions and 11 deletions

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@ -778,6 +778,8 @@ Embeds a web page as a slide background that covers 100% of the reveal.js width
</section> </section>
``` ```
Iframes are lazy-loaded when they become visible. If you'd like to preload iframes aehad of time, you can append a `data-preload` attribute to the slide `<section>`. You can also enable preloading globally for all iframes using the `preloadIframes` configuration option.
#### Background Transitions #### Background Transitions
Backgrounds transition using a fade animation by default. This can be changed to a linear sliding transition by passing `backgroundTransition: 'slide'` to the `Reveal.initialize()` call. Alternatively you can set `data-background-transition` on any section with a background to override that specific transition. Backgrounds transition using a fade animation by default. This can be changed to a linear sliding transition by passing `backgroundTransition: 'slide'` to the `Reveal.initialize()` call. Alternatively you can set `data-background-transition` on any section with a background to override that specific transition.

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@ -1217,6 +1217,8 @@
if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor; if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor;
if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition ); if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition );
if( slide.hasAttribute( 'data-preload' ) ) element.setAttribute( 'data-preload', '' );
// Background image options are set on the content wrapper // Background image options are set on the content wrapper
if( data.backgroundSize ) contentElement.style.backgroundSize = data.backgroundSize; if( data.backgroundSize ) contentElement.style.backgroundSize = data.backgroundSize;
if( data.backgroundRepeat ) contentElement.style.backgroundRepeat = data.backgroundRepeat; if( data.backgroundRepeat ) contentElement.style.backgroundRepeat = data.backgroundRepeat;
@ -3625,7 +3627,7 @@
// Stop content inside of previous backgrounds // Stop content inside of previous backgrounds
if( previousBackground ) { if( previousBackground ) {
stopEmbeddedContent( previousBackground ); stopEmbeddedContent( previousBackground, { unloadIframes: !shouldPreload( previousBackground ) } );
} }
@ -3804,6 +3806,7 @@
background.style.display = 'block'; background.style.display = 'block';
var backgroundContent = slide.slideBackgroundContentElement; var backgroundContent = slide.slideBackgroundContentElement;
var backgroundIframe = slide.getAttribute( 'data-background-iframe' );
// If the background contains media, load it // If the background contains media, load it
if( background.hasAttribute( 'data-loaded' ) === false ) { if( background.hasAttribute( 'data-loaded' ) === false ) {
@ -3812,8 +3815,7 @@
var backgroundImage = slide.getAttribute( 'data-background-image' ), var backgroundImage = slide.getAttribute( 'data-background-image' ),
backgroundVideo = slide.getAttribute( 'data-background-video' ), backgroundVideo = slide.getAttribute( 'data-background-video' ),
backgroundVideoLoop = slide.hasAttribute( 'data-background-video-loop' ), backgroundVideoLoop = slide.hasAttribute( 'data-background-video-loop' ),
backgroundVideoMuted = slide.hasAttribute( 'data-background-video-muted' ), backgroundVideoMuted = slide.hasAttribute( 'data-background-video-muted' );
backgroundIframe = slide.getAttribute( 'data-background-iframe' );
// Images // Images
if( backgroundImage ) { if( backgroundImage ) {
@ -3854,14 +3856,7 @@
iframe.setAttribute( 'mozallowfullscreen', '' ); iframe.setAttribute( 'mozallowfullscreen', '' );
iframe.setAttribute( 'webkitallowfullscreen', '' ); iframe.setAttribute( 'webkitallowfullscreen', '' );
// Only load autoplaying content when the slide is shown to iframe.setAttribute( 'data-src', backgroundIframe );
// avoid having it play in the background
if( /autoplay=(1|true|yes)/gi.test( backgroundIframe ) ) {
iframe.setAttribute( 'data-src', backgroundIframe );
}
else {
iframe.setAttribute( 'src', backgroundIframe );
}
iframe.style.width = '100%'; iframe.style.width = '100%';
iframe.style.height = '100%'; iframe.style.height = '100%';
@ -3872,6 +3867,19 @@
} }
} }
// Start loading preloadable iframes
var backgroundIframeElement = backgroundContent.querySelector( 'iframe[data-src]' );
if( backgroundIframeElement ) {
// Check if this iframe is eligible to be preloaded
if( shouldPreload( background ) && !/autoplay=(1|true|yes)/gi.test( backgroundIframe ) ) {
if( backgroundIframeElement.getAttribute( 'src' ) !== backgroundIframe ) {
backgroundIframeElement.setAttribute( 'src', backgroundIframe );
}
}
}
} }
} }
@ -3891,6 +3899,11 @@
var background = getSlideBackground( slide ); var background = getSlideBackground( slide );
if( background ) { if( background ) {
background.style.display = 'none'; background.style.display = 'none';
// Unload any background iframes
toArray( background.querySelectorAll( 'iframe[src]' ) ).forEach( function( element ) {
element.removeAttribute( 'src' );
} );
} }
// Reset lazy-loaded media elements with src attributes // Reset lazy-loaded media elements with src attributes

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@ -0,0 +1,104 @@
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>reveal.js - Test Iframe Backgrounds</title>
<link rel="stylesheet" href="../css/reveal.css">
<link rel="stylesheet" href="qunit-2.5.0.css">
</head>
<body style="overflow: auto;">
<div id="qunit"></div>
<div id="qunit-fixture"></div>
<div class="reveal" style="display: none;">
<div class="slides">
<section data-background-iframe="#1">1</section>
<section data-background-iframe="#2">2</section>
<section data-background-iframe="#3" data-preload>3</section>
<section data-background-iframe="#4">4</section>
<section data-background-iframe="#5">5</section>
<section data-background-iframe="#6">6</section>
</div>
</div>
<script src="../js/reveal.js"></script>
<script src="qunit-2.5.0.js"></script>
<script>
Reveal.addEventListener( 'ready', function() {
function getIframe( index ) {
return document.querySelectorAll( '.slide-background' )[index].querySelector( 'iframe' );
}
QUnit.module( 'Iframe' );
QUnit.test( 'Using default settings', function( assert ) {
Reveal.slide(0);
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), false, 'not preloaded when within viewDistance' );
Reveal.slide(1);
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), true, 'loaded when slide becomes visible' );
Reveal.slide(0);
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), false, 'unloaded when slide becomes invisible' );
});
QUnit.test( 'Using data-preload', function( assert ) {
Reveal.slide(1);
assert.strictEqual( getIframe(2).hasAttribute( 'src' ), true, 'preloaded within viewDistance' );
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), true, 'loaded when slide becomes visible' );
Reveal.slide(0);
assert.strictEqual( getIframe(3).hasAttribute( 'src' ), false, 'unloads outside of viewDistance' );
});
QUnit.test( 'Using preloadIframes: true', function( assert ) {
Reveal.configure({ preloadIframes: true });
Reveal.slide(1);
assert.strictEqual( getIframe(0).hasAttribute( 'src' ), true, 'preloaded within viewDistance' );
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), true, 'preloaded within viewDistance' );
assert.strictEqual( getIframe(2).hasAttribute( 'src' ), true, 'preloaded within viewDistance' );
});
QUnit.test( 'Using preloadIframes: false', function( assert ) {
Reveal.configure({ preloadIframes: false });
Reveal.slide(0);
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), false, 'not preloaded within viewDistance' );
assert.strictEqual( getIframe(2).hasAttribute( 'src' ), false, 'not preloaded within viewDistance' );
Reveal.slide(1);
assert.strictEqual( getIframe(1).hasAttribute( 'src' ), true, 'loaded when slide becomes visible' );
});
} );
Reveal.initialize({
viewDistance: 3
});
</script>
</body>
</html>