gecko-dev/dom/media/GVAutoplayPermissionRequest.h

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3.5 KiB
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/* 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/. */
#ifndef DOM_MEDIA_GVAUTOPLAYPERMISSIONREQUEST_H_
#define DOM_MEDIA_GVAUTOPLAYPERMISSIONREQUEST_H_
#include "GVAutoplayRequestUtils.h"
#include "nsContentPermissionHelper.h"
namespace mozilla {
namespace dom {
/**
* This class is used to provide an ability for GeckoView (GV) to allow its
* embedder (application) to decide whether the autoplay media should be allowed
* or denied on the page. We have two types of request, one for audible media,
* another one for inaudible media. Each page would at most have one request per
* type at a time, and the result of request would be effective on that page
* until the page gets reloaded or closed.
*/
class GVAutoplayPermissionRequest : public ContentPermissionRequestBase {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(GVAutoplayPermissionRequest,
ContentPermissionRequestBase)
// nsIContentPermissionRequest methods
NS_IMETHOD Cancel(void) override;
NS_IMETHOD Allow(JS::HandleValue choices) override;
private:
// Only allow to create this request from the requestor.
friend class GVAutoplayPermissionRequestor;
static void CreateRequest(nsGlobalWindowInner* aWindow,
BrowsingContext* aContext,
GVAutoplayRequestType aType);
GVAutoplayPermissionRequest(nsGlobalWindowInner* aWindow,
BrowsingContext* aContext,
GVAutoplayRequestType aType);
~GVAutoplayPermissionRequest();
void SetRequestStatus(GVAutoplayRequestStatus aStatus);
GVAutoplayRequestType mType;
RefPtr<BrowsingContext> mContext;
};
/**
* This class provides a method to request autoplay permission for a page, which
* would be used to be a factor to determine if media is allowed to autoplay or
* not on GeckoView.
*
* A page could only have at most one audible request and one inaudible request,
* and once a page has been closed or reloaded, those requests would be dropped.
* In order to achieve that all media existing in the same page can share the
* result of those requests, the request status would only be stored in the
* top-level browsing context, which allows them to be synchronized among
* different processes when Fission is enabled.
*
* The current way we choose is to request for a permission when creating media
* element, in order to get the response from the embedding app before media
* starts playing if the app can response the request quickly enough. However,
* the request might be pending if the app doesn't response to it, we might
* never get the response. As that is just one factor of determining the
* autoplay result, even if we don't get the response for the request, we still
* have a chance to play media. Check AutoplayPolicy to see more details about
* how we decide the final autoplay decision.
*/
class GVAutoplayPermissionRequestor final {
public:
static void AskForPermissionIfNeeded(nsPIDOMWindowInner* aWindow);
private:
static bool HasEverAskForRequest(BrowsingContext* aContext,
GVAutoplayRequestType aType);
static void CreateAsyncRequest(nsPIDOMWindowInner* aWindow,
BrowsingContext* aContext,
GVAutoplayRequestType aType);
};
} // namespace dom
} // namespace mozilla
#endif