render_widget_host.h | Explore in Territory

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_
#define CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_

#include <stdint.h>

#include <memory>
#include <optional>
#include <vector>

#include "base/functional/callback.h"
#include "base/i18n/rtl.h"
#include "base/scoped_observation_traits.h"
#include "build/build_config.h"
#include "components/input/native_web_keyboard_event.h"
#include "content/common/content_export.h"
#include "content/public/common/drop_data.h"
#include "ipc/ipc_channel.h"
#include "ipc/ipc_sender.h"
#include "third_party/blink/public/common/input/web_gesture_event.h"
#include "third_party/blink/public/common/input/web_input_event.h"
#include "third_party/blink/public/common/page/drag_operation.h"
#include "third_party/blink/public/mojom/input/input_event_result.mojom-shared.h"
#include "third_party/perfetto/include/perfetto/tracing/traced_value_forward.h"
#include "ui/base/dragdrop/mojom/drag_drop_types.mojom-forward.h"
#include "ui/base/ui_base_types.h"
#include "ui/display/screen_infos.h"
#include "ui/surface/transport_dib.h"

namespace blink {
class WebMouseEvent;
class WebMouseWheelEvent;
}

namespace cc {
enum class TouchAction;
}

namespace display {
struct ScreenInfo;
}

namespace gfx {
class Point;
}

namespace ui {
class Cursor;
class LatencyInfo;
}

namespace viz {
class FrameSinkId;
}

namespace content {
class RenderProcessHost;
class RenderWidgetHostIterator;
class RenderWidgetHostObserver;
class RenderWidgetHostView;

// A RenderWidgetHost acts as the abstraction for compositing and input
// functionality. It can exist in 3 different scenarios:
//
// 1. Popups, which are spawned in situations like <select> menus or
//    HTML calendar widgets. These are browser-implemented widgets that
//    are created and owned by WebContents in response to a renderer
//    request. Since they are divorced from the web page (they are not
//    clipped to the bounds of the page), they are an independent
//    compositing and input target. As they are owned by WebContents,
//    they are also destroyed by WebContents.
//
// 2. Main frames, which are a root frame of a WebContents. These frames
//    are separated from the browser UI for compositing and input, as the
//    renderer lives in its own coordinate space. These are attached to
//    the lifetime of the main frame (currently, owned by the
//    RenderViewHost, though that should change one day as per
//    https://crbug.com/419087).
//
// 3. Child local root frames, which are iframes isolated from their
//    parent frame for security or performance purposes. This allows
//    them to be placed in an arbitrary process relative to their
//    parent frame. Since they are isolated from the parent, they live
//    in their own coordinate space and are an independent unit of
//    compositing and input. These are attached to the lifetime of
//    the local root frame, and are explicitly owned by the
//    RenderFrameHost.
//
// A RenderWidgetHost is platform-agnostic. It defers platform-specific
// behaviour to its RenderWidgetHostView, which ties the compositing
// output into the native browser UI. Child local root frames also have
// a separate "platform" RenderWidgetHostView type at this time, though
// it stretches the abstraction uncomfortably.
//
// The RenderWidgetHostView has a complex and somewhat broken lifetime as
// of this writing (see, e.g. https://crbug.com/1161585). It is eagerly
// created along with the RenderWidgetHost on the first creation, before
// the renderer process may exist. It is destroyed if the renderer process
// exits, and not recreated at that time. Then it is recreated lazily when
// the associated renderer frame/widget is recreated.
class CONTENT_EXPORT RenderWidgetHost { … };

}  // namespace content

namespace base {
template <>
struct ScopedObservationTraits<content::RenderWidgetHost,
                               content::RenderWidgetHost::InputEventObserver> { … };
}  // namespace base

#endif  // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_
chromium/content/public/browser/render_widget_host.h
