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content / public / browser / render_widget_host.h [blame]
// 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/mojom/menu_source_type.mojom-forward.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 {
public:
// Returns the RenderWidgetHost given its ID and the ID of its render process.
// Returns nullptr if the IDs do not correspond to a live RenderWidgetHost.
static RenderWidgetHost* FromID(int32_t process_id, int32_t routing_id);
// Returns an iterator over the global list of active RenderWidgetHosts.
static std::unique_ptr<RenderWidgetHostIterator> GetRenderWidgetHosts();
virtual ~RenderWidgetHost() {}
// Returns the viz::FrameSinkId that this object uses to put things on screen.
// This value is constant throughout the lifetime of this object. Note that
// until a RenderWidgetHostView is created, initialized, and assigned to this
// object, viz may not be aware of this FrameSinkId.
virtual const viz::FrameSinkId& GetFrameSinkId() = 0;
// Update the text direction of the focused input element and notify it to a
// renderer process.
// These functions have two usage scenarios: changing the text direction
// from a menu (as Safari does), and; changing the text direction when a user
// presses a set of keys (as IE and Firefox do).
// 1. Change the text direction from a menu.
// In this scenario, we receive a menu event only once and we should update
// the text direction immediately when a user chooses a menu item. So, we
// should call both functions at once as listed in the following snippet.
// void RenderViewHost::SetTextDirection(
// base::i18n::TextDirection direction) {
// UpdateTextDirection(direction);
// NotifyTextDirection();
// }
// 2. Change the text direction when pressing a set of keys.
// Because of auto-repeat, we may receive the same key-press event many
// times while we presses the keys and it is nonsense to send the same IPC
// message every time when we receive a key-press event.
// To suppress the number of IPC messages, we just update the text direction
// when receiving a key-press event and send an IPC message when we release
// the keys as listed in the following snippet.
// if (key_event.type == WebKeyboardEvent::KEY_DOWN) {
// if (key_event.windows_key_code == 'A' &&
// key_event.modifiers == WebKeyboardEvent::CTRL_KEY) {
// UpdateTextDirection(dir);
// } else {
// CancelUpdateTextDirection();
// }
// } else if (key_event.type == WebKeyboardEvent::KEY_UP) {
// NotifyTextDirection();
// }
// Once we cancel updating the text direction, we have to ignore all
// succeeding UpdateTextDirection() requests until calling
// NotifyTextDirection(). (We may receive keydown events even after we
// canceled updating the text direction because of auto-repeat.)
// Note: we cannot undo this change for compatibility with Firefox and IE.
virtual void UpdateTextDirection(base::i18n::TextDirection direction) = 0;
virtual void NotifyTextDirection() = 0;
virtual void Focus() = 0;
virtual void Blur() = 0;
// Tests may need to flush IPCs to ensure deterministic behavior.
virtual void FlushForTesting() = 0;
// Sets whether the renderer should show controls in an active state. On all
// platforms except mac, that's the same as focused. On mac, the frontmost
// window will show active controls even if the focus is not in the web
// contents, but e.g. in the omnibox.
virtual void SetActive(bool active) = 0;
// Forwards the given message to the renderer. These are called by
// the view when it has received a message.
virtual void ForwardMouseEvent(
const blink::WebMouseEvent& mouse_event) = 0;
virtual void ForwardWheelEvent(
const blink::WebMouseWheelEvent& wheel_event) = 0;
virtual void ForwardKeyboardEvent(
const input::NativeWebKeyboardEvent& key_event) = 0;
virtual void ForwardKeyboardEventWithLatencyInfo(
const input::NativeWebKeyboardEvent& key_event,
const ui::LatencyInfo& latency_info) = 0;
virtual void ForwardGestureEvent(
const blink::WebGestureEvent& gesture_event) = 0;
virtual RenderProcessHost* GetProcess() = 0;
virtual int GetRoutingID() = 0;
// Gets the View of this RenderWidgetHost. Can be nullptr, e.g. if the
// RenderWidget is being destroyed or the render process crashed. You should
// never cache this pointer since it can become nullptr if the renderer
// crashes, instead you should always ask for it using the accessor.
virtual RenderWidgetHostView* GetView() = 0;
// Returns true if the renderer is considered unresponsive.
virtual bool IsCurrentlyUnresponsive() = 0;
// Called to propagate updated visual properties to the renderer. Returns
// true if visual properties have changed since last call.
virtual bool SynchronizeVisualProperties() = 0;
// Access to the implementation's IPC::Listener::OnMessageReceived. Intended
// only for test code.
// Add/remove a callback that can handle key presses without requiring focus.
using KeyPressEventCallback =
base::RepeatingCallback<bool(const input::NativeWebKeyboardEvent&)>;
virtual void AddKeyPressEventCallback(
const KeyPressEventCallback& callback) = 0;
virtual void RemoveKeyPressEventCallback(
const KeyPressEventCallback& callback) = 0;
// Add/remove a callback that can handle all kinds of mouse events.
using MouseEventCallback =
base::RepeatingCallback<bool(const blink::WebMouseEvent&)>;
virtual void AddMouseEventCallback(const MouseEventCallback& callback) = 0;
virtual void RemoveMouseEventCallback(const MouseEventCallback& callback) = 0;
// Adds a callback that, when it returns true, will suppress IME
// display.
using SuppressShowingImeCallback = base::RepeatingCallback<bool()>;
virtual void AddSuppressShowingImeCallback(
const SuppressShowingImeCallback& callback) = 0;
// Removes the callback to suppress IME display. If `trigger_ime` is set tu
// true, it will also try to show the IME display after the callback removal.
virtual void RemoveSuppressShowingImeCallback(
const SuppressShowingImeCallback& callback,
bool trigger_ime) = 0;
// Observer for WebInputEvents.
class InputEventObserver {
public:
virtual ~InputEventObserver() {}
virtual void OnInputEvent(const blink::WebInputEvent&) {}
virtual void OnInputEventAck(blink::mojom::InputEventResultSource source,
blink::mojom::InputEventResultState state,
const blink::WebInputEvent&) {}
#if BUILDFLAG(IS_ANDROID)
// Not all key events are triggered through InputEvent on Android.
// InputEvents are only triggered when user typed in through number bar on
// Android keyboard. This function is triggered when text is committed in
// input form.
virtual void OnImeTextCommittedEvent(const std::u16string& text_str) {}
// This function is triggered when composing text is updated. Note that
// text_str contains all text that is currently under composition rather
// than updated text only.
virtual void OnImeSetComposingTextEvent(const std::u16string& text_str) {}
// This function is triggered when composing text is filled into the input
// form.
virtual void OnImeFinishComposingTextEvent() {}
#endif
};
// Add/remove an input event observer.
virtual void AddInputEventObserver(InputEventObserver* observer) = 0;
virtual void RemoveInputEventObserver(InputEventObserver* observer) = 0;
#if BUILDFLAG(IS_ANDROID)
// Add/remove an Ime input event observer.
virtual void AddImeInputEventObserver(InputEventObserver* observer) = 0;
virtual void RemoveImeInputEventObserver(InputEventObserver* observer) = 0;
#endif
// Add and remove observers for widget host events. The order in which
// notifications are sent to observers is undefined. Observers must be sure to
// remove the observer before they go away.
virtual void AddObserver(RenderWidgetHostObserver* observer) = 0;
virtual void RemoveObserver(RenderWidgetHostObserver* observer) = 0;
// Get info regarding the screen showing this RenderWidgetHost.
virtual display::ScreenInfo GetScreenInfo() const = 0;
// Get info regarding all screens, including which screen is currently showing
// this RenderWidgetHost.
virtual display::ScreenInfos GetScreenInfos() const = 0;
// This must always return the same device scale factor as GetScreenInfo.
virtual float GetDeviceScaleFactor() = 0;
// Get the allowed touch action corresponding to this RenderWidgetHost.
virtual std::optional<cc::TouchAction> GetAllowedTouchAction() = 0;
// Write a representation of this object into a trace.
virtual void WriteIntoTrace(perfetto::TracedValue context) = 0;
using DragOperationCallback =
base::OnceCallback<void(::ui::mojom::DragOperation, bool)>;
// Drag-and-drop drop target messages that get sent to Blink.
virtual void DragTargetDragEnter(const DropData& drop_data,
const gfx::PointF& client_pt,
const gfx::PointF& screen_pt,
blink::DragOperationsMask operations_allowed,
int key_modifiers,
DragOperationCallback callback) {}
virtual void DragTargetDragEnterWithMetaData(
const std::vector<DropData::Metadata>& metadata,
const gfx::PointF& client_pt,
const gfx::PointF& screen_pt,
blink::DragOperationsMask operations_allowed,
int key_modifiers,
DragOperationCallback callback) {}
virtual void DragTargetDragOver(const gfx::PointF& client_pt,
const gfx::PointF& screen_pt,
blink::DragOperationsMask operations_allowed,
int key_modifiers,
DragOperationCallback callback) {}
virtual void DragTargetDragLeave(const gfx::PointF& client_point,
const gfx::PointF& screen_point) {}
virtual void DragTargetDrop(const DropData& drop_data,
const gfx::PointF& client_pt,
const gfx::PointF& screen_pt,
int key_modifiers,
base::OnceClosure callback) {}
// Notifies the renderer that a drag operation that it started has ended,
// either in a drop or by being cancelled.
virtual void DragSourceEndedAt(const gfx::PointF& client_pt,
const gfx::PointF& screen_pt,
ui::mojom::DragOperation operation,
base::OnceClosure callback) {}
// Notifies the renderer that we're done with the drag and drop operation.
// This allows the renderer to reset some state.
virtual void DragSourceSystemDragEnded() {}
// Filters drop data before it is passed to RenderWidgetHost.
virtual void FilterDropData(DropData* drop_data) {}
// Sets cursor to a specified one when it is over this widget.
virtual void SetCursor(const ui::Cursor& cursor) {}
// Shows the context menu using the specified point as anchor point.
virtual void ShowContextMenuAtPoint(
const gfx::Point& point,
const ui::mojom::MenuSourceType source_type) {}
// Roundtrips through the renderer and compositor pipeline to ensure that any
// changes to the contents resulting from operations executed prior to this
// call are visible on screen. The call completes asynchronously (if it
// succeeds) by running the supplied |callback| with a value of true upon
// successful completion and false otherwise when the widget is destroyed.
// This can run synchronously on failure.
using VisualStateCallback = base::OnceCallback<void(bool)>;
virtual void InsertVisualStateCallback(VisualStateCallback callback) {}
};
} // namespace content
namespace base {
template <>
struct ScopedObservationTraits<content::RenderWidgetHost,
content::RenderWidgetHost::InputEventObserver> {
static void AddObserver(
content::RenderWidgetHost* rwh,
content::RenderWidgetHost::InputEventObserver* observer) {
rwh->AddInputEventObserver(observer);
}
static void RemoveObserver(
content::RenderWidgetHost* rwh,
content::RenderWidgetHost::InputEventObserver* observer) {
rwh->RemoveInputEventObserver(observer);
}
};
} // namespace base
#endif // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_