offscreen_tab.h | Explore in Territory

// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_MEDIA_OFFSCREEN_TAB_H_
#define CHROME_BROWSER_MEDIA_OFFSCREEN_TAB_H_

#include <stdint.h>

#include <memory>
#include <string>

#include "base/memory/raw_ptr.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "chrome/browser/profiles/profile_observer.h"
#include "content/public/browser/web_contents_delegate.h"
#include "content/public/browser/web_contents_observer.h"
#include "ui/gfx/geometry/size.h"

namespace media_router {
class NavigationPolicy;
}  // namespace media_router

namespace content {
class BrowserContext;
}  // namespace content

// Owns and controls a sandboxed WebContents instance hosting the rendering
// engine for an offscreen tab.  Since the offscreen tab does not interact with
// the user in any direct way, the WebContents is not attached to any Browser
// window/UI, and any input and focusing capabilities are blocked.
//
// An OffscreenTab instance is shut down one of the three ways:
//
//   1. When WebContents::IsBeingCaptured() returns false, indicating there are
//      no more consumers of its captured content (e.g., when all MediaStreams
//      have been closed).  OffscreenTab will auto-detect this case and
//      self-destruct.
//   2. By the renderer, where the WebContents implementation will invoke the
//      WebContentsDelegate::CloseContents() override.  This occurs, for
//      example, when a page calls window.close().
//   3. Automatically, when the associated profile is destroyed.
//
// This class operates exclusively on the UI thread and so is not thread-safe.
class OffscreenTab final : public ProfileObserver,
                           protected content::WebContentsDelegate,
                           protected content::WebContentsObserver { … };

#endif  // CHROME_BROWSER_MEDIA_OFFSCREEN_TAB_H_
chromium/chrome/browser/media/offscreen_tab.h
