gecko-dev/dom/media/AutoplayPolicy.h

61 строка
2.1 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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/. */
#if !defined(AutoplayPolicy_h_)
#define AutoplayPolicy_h_
#include "mozilla/NotNull.h"
class nsIDocument;
namespace mozilla {
class AutoplayPermissionManager;
namespace dom {
class HTMLMediaElement;
class AudioContext;
/**
* AutoplayPolicy is used to manage autoplay logic for all kinds of media,
* including MediaElement, Web Audio and Web Speech.
*
* Autoplay could be disable by setting the pref "media.autoplay.default"
* to anything but nsIAutoplay::Allowed. Once user disables autoplay, media
* could only be played if one of following conditions is true.
* 1) Owner document is activated by user gestures
* We restrict user gestures to "mouse click", "keyboard press" and "touch".
* 2) Muted media content or video without audio content.
* 3) Document's origin has the "autoplay-media" permission.
*/
class AutoplayPolicy
{
public:
// Returns whether a given media element is allowed to play.
static bool IsAllowedToPlay(const HTMLMediaElement& aElement);
// Returns whether a given AudioContext is allowed to play.
static bool IsAllowedToPlay(const AudioContext& aContext);
// Returns true if a given media element would be allowed to play
// if block autoplay was enabled. If this returns false, it means we would
// either block or ask for permission.
// Note: this is for telemetry purposes, and doesn't check the prefs
// which enable/disable block autoplay. Do not use for blocking logic!
static bool WouldBeAllowedToPlayIfAutoplayDisabled(const HTMLMediaElement& aElement);
// Returns the AutoplayPermissionManager that a given document must request on
// for autoplay permission.
static already_AddRefed<AutoplayPermissionManager> RequestFor(
const nsIDocument& aDocument);
};
} // namespace dom
} // namespace mozilla
#endif