fune/toolkit/content/TopLevelVideoDocument.js
Timothy Guan-tin Chien 80558b2dbc Bug 1484544 - Allow focusable element to function on top level video element r=Gijs
Differential Revision: https://phabricator.services.mozilla.com/D4169

--HG--
extra : moz-landing-system : lando
2018-08-24 17:37:15 +00:00

63 lines
2.2 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
// Hide our variables from the web content, even though the spec allows them
// (and the DOM) to be accessible (see bug 1474832)
{
// <video> is used for top-level audio documents as well
let videoElement = document.getElementsByTagName("video")[0];
let setFocusToVideoElement = function(e) {
// We don't want to retarget focus if it goes to the controls in
// the video element. Because they're anonymous content, the target
// will be the video element in that case. Avoid calling .focus()
// for those events:
if (e && e.target == videoElement) {
return;
}
videoElement.focus();
};
// Redirect focus to the video element whenever the document receives
// focus.
document.addEventListener("focus", setFocusToVideoElement, true);
// Focus on the video in the newly created document.
setFocusToVideoElement();
// Opt out of moving focus away if the DOM tree changes (from add-on or web content)
let observer = new MutationObserver(
() => {
observer.disconnect();
document.removeEventListener("focus", setFocusToVideoElement, true);
});
observer.observe(document.documentElement, { childList: true, subtree: true });
// Handle fullscreen mode
document.addEventListener("keypress", ev => {
// Maximize the standalone video when pressing F11,
// but ignore audio elements
if (ev.key == "F11" && videoElement.videoWidth != 0 && videoElement.videoHeight != 0) {
// If we're in browser fullscreen mode, it means the user pressed F11
// while browser chrome or another tab had focus.
// Don't break leaving that mode, so do nothing here.
if (window.fullScreen) {
return;
}
// If we're not in browser fullscreen mode, prevent entering into that,
// so we don't end up there after pressing Esc.
ev.preventDefault();
ev.stopPropagation();
if (!document.mozFullScreenElement) {
videoElement.mozRequestFullScreen();
} else {
document.mozCancelFullScreen();
}
}
});
}