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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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 nsIWidget_h__
+#define nsIWidget_h__
+
+#include <cmath>
+#include <cstdint>
+#include "imgIContainer.h"
+#include "ErrorList.h"
+#include "Units.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/EventForwards.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/gfx/Matrix.h"
+#include "mozilla/gfx/Rect.h"
+#include "mozilla/layers/LayersTypes.h"
+#include "mozilla/layers/ScrollableLayerGuid.h"
+#include "mozilla/layers/ZoomConstraints.h"
+#include "mozilla/image/Resolution.h"
+#include "mozilla/widget/IMEData.h"
+#include "nsCOMPtr.h"
+#include "nsColor.h"
+#include "nsDebug.h"
+#include "nsID.h"
+#include "nsIObserver.h"
+#include "nsISupports.h"
+#include "nsITheme.h"
+#include "nsITimer.h"
+#include "nsIWidgetListener.h"
+#include "nsRect.h"
+#include "nsSize.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nsTHashMap.h"
+#include "mozilla/widget/InitData.h"
+#include "nsXULAppAPI.h"
+
+// forward declarations
+class nsIBidiKeyboard;
+class nsIRollupListener;
+class nsIContent;
+class ViewWrapper;
+class nsIRunnable;
+
+namespace mozilla {
+enum class NativeKeyBindingsType : uint8_t;
+class VsyncDispatcher;
+class WidgetGUIEvent;
+class WidgetInputEvent;
+class WidgetKeyboardEvent;
+struct FontRange;
+
+enum class StyleWindowShadow : uint8_t;
+enum class ColorScheme : uint8_t;
+enum class WindowButtonType : uint8_t;
+
+#if defined(MOZ_WIDGET_ANDROID)
+namespace ipc {
+class Shmem;
+}
+#endif // defined(MOZ_WIDGET_ANDROID)
+namespace dom {
+class BrowserChild;
+enum class CallerType : uint32_t;
+} // namespace dom
+class WindowRenderer;
+namespace layers {
+class AsyncDragMetrics;
+class Compositor;
+class CompositorBridgeChild;
+struct FrameMetrics;
+class LayerManager;
+class WebRenderBridgeChild;
+} // namespace layers
+namespace widget {
+class TextEventDispatcher;
+class TextEventDispatcherListener;
+class CompositorWidget;
+class CompositorWidgetInitData;
+class Screen;
+} // namespace widget
+namespace wr {
+class DisplayListBuilder;
+class IpcResourceUpdateQueue;
+enum class RenderRoot : uint8_t;
+} // namespace wr
+} // namespace mozilla
+
+/**
+ * Callback function that processes events.
+ *
+ * The argument is actually a subtype (subclass) of WidgetEvent which carries
+ * platform specific information about the event. Platform specific code
+ * knows how to deal with it.
+ *
+ * The return value determines whether or not the default action should take
+ * place.
+ */
+typedef nsEventStatus (*EVENT_CALLBACK)(mozilla::WidgetGUIEvent* aEvent);
+
+// Hide the native window system's real window type so as to avoid
+// including native window system types and APIs. This is necessary
+// to ensure cross-platform code.
+typedef void* nsNativeWidget;
+
+/**
+ * Values for the GetNativeData function
+ */
+#define NS_NATIVE_WINDOW 0
+#define NS_NATIVE_GRAPHIC 1
+#define NS_NATIVE_WIDGET 3
+#define NS_NATIVE_REGION 5
+#define NS_NATIVE_OFFSETX 6
+#define NS_NATIVE_OFFSETY 7
+#define NS_NATIVE_SCREEN 9
+// The toplevel GtkWidget containing this nsIWidget:
+#define NS_NATIVE_SHELLWIDGET 10
+#define NS_NATIVE_OPENGL_CONTEXT 12
+// This is available only with GetNativeData() in parent process. Anybody
+// shouldn't access this pointer as a valid pointer since the result may be
+// special value like NS_ONLY_ONE_NATIVE_IME_CONTEXT. So, the result is just
+// an identifier of distinguishing a text composition is caused by which native
+// IME context. Note that the result is only valid in the process. So,
+// XP code should use nsIWidget::GetNativeIMEContext() instead of using this.
+#define NS_RAW_NATIVE_IME_CONTEXT 14
+#define NS_NATIVE_WINDOW_WEBRTC_DEVICE_ID 15
+#ifdef XP_WIN
+# define NS_NATIVE_TSF_THREAD_MGR 100
+# define NS_NATIVE_TSF_CATEGORY_MGR 101
+# define NS_NATIVE_TSF_DISPLAY_ATTR_MGR 102
+# define NS_NATIVE_ICOREWINDOW 103 // winrt specific
+#endif
+#if defined(MOZ_WIDGET_GTK)
+# define NS_NATIVE_EGL_WINDOW 106
+#endif
+#ifdef MOZ_WIDGET_ANDROID
+# define NS_JAVA_SURFACE 100
+#endif
+
+#define MOZ_WIDGET_MAX_SIZE 16384
+#define MOZ_WIDGET_INVALID_SCALE 0.0
+
+// Must be kept in sync with xpcom/rust/xpcom/src/interfaces/nonidl.rs
+#define NS_IWIDGET_IID \
+ { \
+ 0x06396bf6, 0x2dd8, 0x45e5, { \
+ 0xac, 0x45, 0x75, 0x26, 0x53, 0xb1, 0xc9, 0x80 \
+ } \
+ }
+
+/**
+ * Cursor types.
+ */
+
+enum nsCursor { ///(normal cursor, usually rendered as an arrow)
+ eCursor_standard,
+ ///(system is busy, usually rendered as a hourglass or watch)
+ eCursor_wait,
+ ///(Selecting something, usually rendered as an IBeam)
+ eCursor_select,
+ ///(can hyper-link, usually rendered as a human hand)
+ eCursor_hyperlink,
+ ///(north/south/west/east edge sizing)
+ eCursor_n_resize,
+ eCursor_s_resize,
+ eCursor_w_resize,
+ eCursor_e_resize,
+ ///(corner sizing)
+ eCursor_nw_resize,
+ eCursor_se_resize,
+ eCursor_ne_resize,
+ eCursor_sw_resize,
+ eCursor_crosshair,
+ eCursor_move,
+ eCursor_help,
+ eCursor_copy, // CSS3
+ eCursor_alias,
+ eCursor_context_menu,
+ eCursor_cell,
+ eCursor_grab,
+ eCursor_grabbing,
+ eCursor_spinning,
+ eCursor_zoom_in,
+ eCursor_zoom_out,
+ eCursor_not_allowed,
+ eCursor_col_resize,
+ eCursor_row_resize,
+ eCursor_no_drop,
+ eCursor_vertical_text,
+ eCursor_all_scroll,
+ eCursor_nesw_resize,
+ eCursor_nwse_resize,
+ eCursor_ns_resize,
+ eCursor_ew_resize,
+ eCursor_none,
+ // This one is used for array sizing, and so better be the last
+ // one in this list...
+ eCursorCount,
+
+ // ...except for this one.
+ eCursorInvalid = eCursorCount + 1
+};
+
+enum nsTopLevelWidgetZPlacement { // for PlaceBehind()
+ eZPlacementBottom = 0, // bottom of the window stack
+ eZPlacementBelow, // just below another widget
+ eZPlacementTop // top of the window stack
+};
+
+/**
+ * Before the OS goes to sleep, this topic is notified.
+ */
+#define NS_WIDGET_SLEEP_OBSERVER_TOPIC "sleep_notification"
+
+/**
+ * After the OS wakes up, this topic is notified.
+ */
+#define NS_WIDGET_WAKE_OBSERVER_TOPIC "wake_notification"
+
+/**
+ * Before the OS suspends the current process, this topic is notified. Some
+ * OS will kill processes that are suspended instead of resuming them.
+ * For that reason this topic may be useful to safely close down resources.
+ */
+#define NS_WIDGET_SUSPEND_PROCESS_OBSERVER_TOPIC "suspend_process_notification"
+
+/**
+ * After the current process resumes from being suspended, this topic is
+ * notified.
+ */
+#define NS_WIDGET_RESUME_PROCESS_OBSERVER_TOPIC "resume_process_notification"
+
+/**
+ * When an app(-shell) is activated by the OS, this topic is notified.
+ * Currently, this only happens on Mac OSX.
+ */
+#define NS_WIDGET_MAC_APP_ACTIVATE_OBSERVER_TOPIC "mac_app_activate"
+
+namespace mozilla::widget {
+
+/**
+ * Size constraints for setting the minimum and maximum size of a widget.
+ * Values are in device pixels.
+ */
+struct SizeConstraints {
+ SizeConstraints()
+ : mMaxSize(MOZ_WIDGET_MAX_SIZE, MOZ_WIDGET_MAX_SIZE),
+ mScale(MOZ_WIDGET_INVALID_SCALE) {}
+
+ SizeConstraints(mozilla::LayoutDeviceIntSize aMinSize,
+ mozilla::LayoutDeviceIntSize aMaxSize,
+ mozilla::DesktopToLayoutDeviceScale aScale)
+ : mMinSize(aMinSize), mMaxSize(aMaxSize), mScale(aScale) {
+ if (mMaxSize.width > MOZ_WIDGET_MAX_SIZE) {
+ mMaxSize.width = MOZ_WIDGET_MAX_SIZE;
+ }
+ if (mMaxSize.height > MOZ_WIDGET_MAX_SIZE) {
+ mMaxSize.height = MOZ_WIDGET_MAX_SIZE;
+ }
+ }
+
+ mozilla::LayoutDeviceIntSize mMinSize;
+ mozilla::LayoutDeviceIntSize mMaxSize;
+
+ /*
+ * The scale used to convert from desktop to device dimensions.
+ * MOZ_WIDGET_INVALID_SCALE if the value is not known.
+ *
+ * Bug 1701109 is filed to revisit adding of 'mScale' and deal
+ * with multi-monitor scaling issues in more complete way across
+ * all widget implementations.
+ */
+ mozilla::DesktopToLayoutDeviceScale mScale;
+};
+
+struct AutoObserverNotifier {
+ AutoObserverNotifier(nsIObserver* aObserver, const char* aTopic)
+ : mObserver(aObserver), mTopic(aTopic) {}
+
+ void SkipNotification() { mObserver = nullptr; }
+
+ uint64_t SaveObserver() {
+ if (!mObserver) {
+ return 0;
+ }
+ uint64_t observerId = ++sObserverId;
+ sSavedObservers.InsertOrUpdate(observerId, mObserver);
+ SkipNotification();
+ return observerId;
+ }
+
+ ~AutoObserverNotifier() {
+ if (mObserver) {
+ mObserver->Observe(nullptr, mTopic, nullptr);
+ }
+ }
+
+ static void NotifySavedObserver(const uint64_t& aObserverId,
+ const char* aTopic) {
+ nsCOMPtr<nsIObserver> observer = sSavedObservers.Get(aObserverId);
+ if (!observer) {
+ MOZ_ASSERT(aObserverId == 0,
+ "We should always find a saved observer for nonzero IDs");
+ return;
+ }
+
+ sSavedObservers.Remove(aObserverId);
+ observer->Observe(nullptr, aTopic, nullptr);
+ }
+
+ private:
+ nsCOMPtr<nsIObserver> mObserver;
+ const char* mTopic;
+
+ private:
+ static uint64_t sObserverId;
+ static nsTHashMap<uint64_t, nsCOMPtr<nsIObserver>> sSavedObservers;
+};
+
+} // namespace mozilla::widget
+
+/**
+ * The base class for all the widgets. It provides the interface for
+ * all basic and necessary functionality.
+ */
+class nsIWidget : public nsISupports {
+ protected:
+ typedef mozilla::dom::BrowserChild BrowserChild;
+
+ public:
+ typedef mozilla::layers::CompositorBridgeChild CompositorBridgeChild;
+ typedef mozilla::layers::AsyncDragMetrics AsyncDragMetrics;
+ typedef mozilla::layers::FrameMetrics FrameMetrics;
+ typedef mozilla::layers::LayerManager LayerManager;
+ typedef mozilla::WindowRenderer WindowRenderer;
+ typedef mozilla::layers::LayersBackend LayersBackend;
+ typedef mozilla::layers::LayersId LayersId;
+ typedef mozilla::layers::ScrollableLayerGuid ScrollableLayerGuid;
+ typedef mozilla::layers::ZoomConstraints ZoomConstraints;
+ typedef mozilla::widget::IMEEnabled IMEEnabled;
+ typedef mozilla::widget::IMEMessage IMEMessage;
+ typedef mozilla::widget::IMENotification IMENotification;
+ typedef mozilla::widget::IMENotificationRequests IMENotificationRequests;
+ typedef mozilla::widget::IMEState IMEState;
+ typedef mozilla::widget::InputContext InputContext;
+ typedef mozilla::widget::InputContextAction InputContextAction;
+ typedef mozilla::widget::NativeIMEContext NativeIMEContext;
+ typedef mozilla::widget::SizeConstraints SizeConstraints;
+ typedef mozilla::widget::TextEventDispatcher TextEventDispatcher;
+ typedef mozilla::widget::TextEventDispatcherListener
+ TextEventDispatcherListener;
+ typedef mozilla::LayoutDeviceIntMargin LayoutDeviceIntMargin;
+ typedef mozilla::LayoutDeviceIntPoint LayoutDeviceIntPoint;
+ typedef mozilla::LayoutDeviceIntRect LayoutDeviceIntRect;
+ typedef mozilla::LayoutDeviceIntRegion LayoutDeviceIntRegion;
+ typedef mozilla::LayoutDeviceIntSize LayoutDeviceIntSize;
+ typedef mozilla::ScreenIntPoint ScreenIntPoint;
+ typedef mozilla::ScreenIntMargin ScreenIntMargin;
+ typedef mozilla::ScreenIntSize ScreenIntSize;
+ typedef mozilla::ScreenPoint ScreenPoint;
+ typedef mozilla::CSSToScreenScale CSSToScreenScale;
+ typedef mozilla::DesktopIntRect DesktopIntRect;
+ typedef mozilla::DesktopPoint DesktopPoint;
+ typedef mozilla::DesktopIntPoint DesktopIntPoint;
+ typedef mozilla::DesktopRect DesktopRect;
+ typedef mozilla::DesktopSize DesktopSize;
+ typedef mozilla::CSSPoint CSSPoint;
+ typedef mozilla::CSSRect CSSRect;
+
+ using InitData = mozilla::widget::InitData;
+ using WindowType = mozilla::widget::WindowType;
+ using PopupType = mozilla::widget::PopupType;
+ using PopupLevel = mozilla::widget::PopupLevel;
+ using BorderStyle = mozilla::widget::BorderStyle;
+ using TransparencyMode = mozilla::widget::TransparencyMode;
+ using Screen = mozilla::widget::Screen;
+
+ // Used in UpdateThemeGeometries.
+ struct ThemeGeometry {
+ // The ThemeGeometryType value for the themed widget, see
+ // nsITheme::ThemeGeometryTypeForWidget.
+ nsITheme::ThemeGeometryType mType;
+ // The device-pixel rect within the window for the themed widget
+ LayoutDeviceIntRect mRect;
+
+ ThemeGeometry(nsITheme::ThemeGeometryType aType,
+ const LayoutDeviceIntRect& aRect)
+ : mType(aType), mRect(aRect) {}
+ };
+
+ NS_DECLARE_STATIC_IID_ACCESSOR(NS_IWIDGET_IID)
+
+ nsIWidget()
+ : mLastChild(nullptr),
+ mPrevSibling(nullptr),
+ mOnDestroyCalled(false),
+ mWindowType(WindowType::Child),
+ mZIndex(0)
+
+ {
+ ClearNativeTouchSequence(nullptr);
+ }
+
+ /**
+ * Create and initialize a widget.
+ *
+ * All the arguments can be null in which case a top level window
+ * with size 0 is created. The event callback function has to be
+ * provided only if the caller wants to deal with the events this
+ * widget receives. The event callback is basically a preprocess
+ * hook called synchronously. The return value determines whether
+ * the event goes to the default window procedure or it is hidden
+ * to the os. The assumption is that if the event handler returns
+ * false the widget does not see the event. The widget should not
+ * automatically clear the window to the background color. The
+ * calling code must handle paint messages and clear the background
+ * itself.
+ *
+ * In practice at least one of aParent and aNativeParent will be null. If
+ * both are null the widget isn't parented (e.g. context menus or
+ * independent top level windows).
+ *
+ * The dimensions given in aRect are specified in the parent's
+ * device coordinate system.
+ * This must not be called for parentless widgets such as top-level
+ * windows, which use the desktop pixel coordinate system; a separate
+ * method is provided for these.
+ *
+ * @param aParent parent nsIWidget
+ * @param aNativeParent native parent widget
+ * @param aRect the widget dimension
+ * @param aInitData data that is used for widget initialization
+ *
+ */
+ [[nodiscard]] virtual nsresult Create(nsIWidget* aParent,
+ nsNativeWidget aNativeParent,
+ const LayoutDeviceIntRect& aRect,
+ InitData* = nullptr) = 0;
+
+ /*
+ * As above, but with aRect specified in DesktopPixel units (for top-level
+ * widgets).
+ * Default implementation just converts aRect to device pixels and calls
+ * through to device-pixel Create, but platforms may override this if the
+ * mapping is not straightforward or the native platform needs to use the
+ * desktop pixel values directly.
+ */
+ [[nodiscard]] virtual nsresult Create(nsIWidget* aParent,
+ nsNativeWidget aNativeParent,
+ const DesktopIntRect& aRect,
+ InitData* aInitData = nullptr) {
+ LayoutDeviceIntRect devPixRect =
+ RoundedToInt(aRect * GetDesktopToDeviceScale());
+ return Create(aParent, aNativeParent, devPixRect, aInitData);
+ }
+
+ /**
+ * Allocate, initialize, and return a widget that is a child of
+ * |this|. The returned widget (if nonnull) has gone through the
+ * equivalent of CreateInstance(widgetCID) + Create(...).
+ *
+ * |CreateChild()| lets widget backends decide whether to parent
+ * the new child widget to this, nonnatively parent it, or both.
+ * This interface exists to support the PuppetWidget backend,
+ * which is entirely non-native. All other params are the same as
+ * for |Create()|.
+ *
+ * |aForceUseIWidgetParent| forces |CreateChild()| to only use the
+ * |nsIWidget*| this, not its native widget (if it exists), when
+ * calling |Create()|. This is a timid hack around poorly
+ * understood code, and shouldn't be used in new code.
+ */
+ virtual already_AddRefed<nsIWidget> CreateChild(
+ const LayoutDeviceIntRect& aRect, InitData* = nullptr,
+ bool aForceUseIWidgetParent = false) = 0;
+
+ /**
+ * Attach to a top level widget.
+ *
+ * In cases where a top level chrome widget is being used as a content
+ * container, attach a secondary listener and update the device
+ * context. The primary widget listener will continue to be called for
+ * notifications relating to the top-level window, whereas other
+ * notifications such as painting and events will instead be called via
+ * the attached listener. SetAttachedWidgetListener should be used to
+ * assign the attached listener.
+ *
+ * aUseAttachedEvents if true, events are sent to the attached listener
+ * instead of the normal listener.
+ */
+ virtual void AttachViewToTopLevel(bool aUseAttachedEvents) = 0;
+
+ /**
+ * Accessor functions to get and set the attached listener. Used by
+ * nsView in connection with AttachViewToTopLevel above.
+ */
+ virtual void SetAttachedWidgetListener(nsIWidgetListener* aListener) = 0;
+ virtual nsIWidgetListener* GetAttachedWidgetListener() const = 0;
+ virtual void SetPreviouslyAttachedWidgetListener(
+ nsIWidgetListener* aListener) = 0;
+ virtual nsIWidgetListener* GetPreviouslyAttachedWidgetListener() = 0;
+
+ /**
+ * Notifies the root widget of a non-blank paint.
+ */
+ virtual void DidGetNonBlankPaint() {}
+
+ /**
+ * Accessor functions to get and set the listener which handles various
+ * actions for the widget.
+ */
+ //@{
+ virtual nsIWidgetListener* GetWidgetListener() const = 0;
+ virtual void SetWidgetListener(nsIWidgetListener* alistener) = 0;
+ //@}
+
+ /**
+ * Close and destroy the internal native window.
+ * This method does not delete the widget.
+ */
+
+ virtual void Destroy() = 0;
+
+ /**
+ * Destroyed() returns true if Destroy() has been called already.
+ * Otherwise, false.
+ */
+ bool Destroyed() const { return mOnDestroyCalled; }
+
+ /**
+ * Reparent a widget
+ *
+ * Change the widget's parent. Null parents are allowed.
+ *
+ * @param aNewParent new parent
+ */
+ virtual void SetParent(nsIWidget* aNewParent) = 0;
+
+ /**
+ * Return the parent Widget of this Widget or nullptr if this is a
+ * top level window
+ *
+ * @return the parent widget or nullptr if it does not have a parent
+ *
+ */
+ virtual nsIWidget* GetParent(void) = 0;
+
+ /**
+ * Return the top level Widget of this Widget
+ *
+ * @return the top level widget
+ */
+ virtual nsIWidget* GetTopLevelWidget() = 0;
+
+ /**
+ * Return the top (non-sheet) parent of this Widget if it's a sheet,
+ * or nullptr if this isn't a sheet (or some other error occurred).
+ * Sheets are only supported on some platforms (currently only macOS).
+ *
+ * @return the top (non-sheet) parent widget or nullptr
+ *
+ */
+ virtual nsIWidget* GetSheetWindowParent(void) = 0;
+
+ /**
+ * Return the physical DPI of the screen containing the window ...
+ * the number of device pixels per inch.
+ */
+ virtual float GetDPI() = 0;
+
+ /**
+ * Fallback DPI for when there's no widget available.
+ */
+ static float GetFallbackDPI();
+
+ /**
+ * Return the scaling factor between device pixels and the platform-
+ * dependent "desktop pixels" used to manage window positions on a
+ * potentially multi-screen, mixed-resolution desktop.
+ */
+ virtual mozilla::DesktopToLayoutDeviceScale GetDesktopToDeviceScale() = 0;
+
+ /**
+ * Return the scaling factor between device pixels and the platform-
+ * dependent "desktop pixels" by looking up the screen by the position
+ * of the widget.
+ */
+ virtual mozilla::DesktopToLayoutDeviceScale
+ GetDesktopToDeviceScaleByScreen() = 0;
+
+ /**
+ * Return the default scale factor for the window. This is the
+ * default number of device pixels per CSS pixel to use. This should
+ * depend on OS/platform settings such as the Mac's "UI scale factor"
+ * or Windows' "font DPI". This will take into account Gecko preferences
+ * overriding the system setting.
+ */
+ mozilla::CSSToLayoutDeviceScale GetDefaultScale();
+
+ /**
+ * Fallback default scale for when there's no widget available.
+ */
+ static mozilla::CSSToLayoutDeviceScale GetFallbackDefaultScale();
+
+ /**
+ * Return the first child of this widget. Will return null if
+ * there are no children.
+ */
+ nsIWidget* GetFirstChild() const { return mFirstChild; }
+
+ /**
+ * Return the last child of this widget. Will return null if
+ * there are no children.
+ */
+ nsIWidget* GetLastChild() const { return mLastChild; }
+
+ /**
+ * Return the next sibling of this widget
+ */
+ nsIWidget* GetNextSibling() const { return mNextSibling; }
+
+ /**
+ * Set the next sibling of this widget
+ */
+ void SetNextSibling(nsIWidget* aSibling) { mNextSibling = aSibling; }
+
+ /**
+ * Return the previous sibling of this widget
+ */
+ nsIWidget* GetPrevSibling() const { return mPrevSibling; }
+
+ /**
+ * Set the previous sibling of this widget
+ */
+ void SetPrevSibling(nsIWidget* aSibling) { mPrevSibling = aSibling; }
+
+ /**
+ * Show or hide this widget
+ *
+ * @param aState true to show the Widget, false to hide it
+ *
+ */
+ virtual void Show(bool aState) = 0;
+
+ /**
+ * Whether or not a widget must be recreated after being hidden to show
+ * again properly.
+ */
+ virtual bool NeedsRecreateToReshow() { return false; }
+
+ /**
+ * Make the window modal.
+ */
+ virtual void SetModal(bool aModal) = 0;
+
+ /**
+ * Make the non-modal window opened by modal window fake-modal, that will
+ * call SetFakeModal(false) on destroy on Cocoa.
+ */
+ virtual void SetFakeModal(bool aModal) { SetModal(aModal); }
+
+ /**
+ * Are we app modal. Currently only implemented on Cocoa.
+ */
+ virtual bool IsRunningAppModal() { return false; }
+
+ /**
+ * The maximum number of simultaneous touch contacts supported by the device.
+ * In the case of devices with multiple digitizers (e.g. multiple touch
+ * screens), the value will be the maximum of the set of maximum supported
+ * contacts by each individual digitizer.
+ */
+ virtual uint32_t GetMaxTouchPoints() const = 0;
+
+ /**
+ * Returns whether the window is visible
+ *
+ */
+ virtual bool IsVisible() const = 0;
+
+ /**
+ * Returns whether the window has allocated resources so
+ * we can paint into it.
+ * Recently it's used on Linux/Gtk where we should not paint
+ * to invisible window.
+ */
+ virtual bool IsMapped() const { return true; }
+
+ /**
+ * Perform platform-dependent sanity check on a potential window position.
+ * This is guaranteed to work only for top-level windows.
+ */
+ virtual void ConstrainPosition(DesktopIntPoint&) = 0;
+
+ /**
+ * NOTE:
+ *
+ * For a top-level window widget, the "parent's coordinate system" is the
+ * "global" display pixel coordinate space, *not* device pixels (which
+ * may be inconsistent between multiple screens, at least in the Mac OS
+ * case with mixed hi-dpi and lo-dpi displays). This applies to all the
+ * following Move and Resize widget APIs.
+ *
+ * The display-/device-pixel distinction becomes important for (at least)
+ * macOS with Hi-DPI (retina) displays, and Windows when the UI scale factor
+ * is set to other than 100%.
+ *
+ * The Move and Resize methods take floating-point parameters, rather than
+ * integer ones. This is important when manipulating top-level widgets,
+ * where the coordinate system may not be an integral multiple of the
+ * device-pixel space.
+ **/
+
+ /**
+ * Move this widget.
+ *
+ * Coordinates refer to the top-left of the widget. For toplevel windows
+ * with decorations, this is the top-left of the titlebar and frame .
+ *
+ * @param aX the new x position expressed in the parent's coordinate system
+ * @param aY the new y position expressed in the parent's coordinate system
+ *
+ **/
+ virtual void Move(double aX, double aY) = 0;
+
+ /**
+ * Reposition this widget so that the client area has the given offset.
+ *
+ * @param aOffset the new offset of the client area expressed as an
+ * offset from the origin of the client area of the parent
+ * widget (for root widgets and popup widgets it is in
+ * screen coordinates)
+ **/
+ virtual void MoveClient(const DesktopPoint& aOffset) = 0;
+
+ /**
+ * Resize this widget. Any size constraints set for the window by a
+ * previous call to SetSizeConstraints will be applied.
+ *
+ * @param aWidth the new width expressed in the parent's coordinate system
+ * @param aHeight the new height expressed in the parent's coordinate
+ * system
+ * @param aRepaint whether the widget should be repainted
+ */
+ virtual void Resize(double aWidth, double aHeight, bool aRepaint) = 0;
+
+ /**
+ * Lock the aspect ratio of a Window
+ *
+ * @param aShouldLock bool
+ *
+ */
+ virtual void LockAspectRatio(bool aShouldLock){};
+
+ /**
+ * Move or resize this widget. Any size constraints set for the window by
+ * a previous call to SetSizeConstraints will be applied.
+ *
+ * @param aX the new x position expressed in the parent's coordinate
+ * system
+ * @param aY the new y position expressed in the parent's coordinate
+ * system
+ * @param aWidth the new width expressed in the parent's coordinate system
+ * @param aHeight the new height expressed in the parent's coordinate
+ * system
+ * @param aRepaint whether the widget should be repainted if the size
+ * changes
+ *
+ */
+ virtual void Resize(double aX, double aY, double aWidth, double aHeight,
+ bool aRepaint) = 0;
+
+ virtual mozilla::Maybe<bool> IsResizingNativeWidget() {
+ return mozilla::Nothing();
+ }
+
+ /**
+ * Resize the widget so that the inner client area has the given size.
+ *
+ * @param aSize the new size of the client area.
+ * @param aRepaint whether the widget should be repainted
+ */
+ virtual void ResizeClient(const DesktopSize& aSize, bool aRepaint) = 0;
+
+ /**
+ * Resize and reposition the widget so tht inner client area has the given
+ * offset and size.
+ *
+ * @param aRect the new offset and size of the client area. The offset is
+ * expressed as an offset from the origin of the client area
+ * of the parent widget (for root widgets and popup widgets it
+ * is in screen coordinates).
+ * @param aRepaint whether the widget should be repainted
+ */
+ virtual void ResizeClient(const DesktopRect& aRect, bool aRepaint) = 0;
+
+ /**
+ * Sets the widget's z-index.
+ */
+ virtual void SetZIndex(int32_t aZIndex) = 0;
+
+ /**
+ * Gets the widget's z-index.
+ */
+ int32_t GetZIndex() { return mZIndex; }
+
+ /**
+ * Position this widget just behind the given widget. (Used to
+ * control z-order for top-level widgets. Get/SetZIndex by contrast
+ * control z-order for child widgets of other widgets.)
+ * @param aPlacement top, bottom, or below a widget
+ * (if top or bottom, param aWidget is ignored)
+ * @param aWidget widget to place this widget behind
+ * (only if aPlacement is eZPlacementBelow).
+ * null is equivalent to aPlacement of eZPlacementTop
+ * @param aActivate true to activate the widget after placing it
+ */
+ virtual void PlaceBehind(nsTopLevelWidgetZPlacement aPlacement,
+ nsIWidget* aWidget, bool aActivate) = 0;
+
+ /**
+ * Minimize, maximize or normalize the window size.
+ * Takes a value from nsSizeMode (see nsIWidgetListener.h)
+ */
+ virtual void SetSizeMode(nsSizeMode aMode) = 0;
+
+ virtual void GetWorkspaceID(nsAString& workspaceID) = 0;
+
+ virtual void MoveToWorkspace(const nsAString& workspaceID) = 0;
+
+ /**
+ * Suppress animations that are applied to a window by OS.
+ */
+ virtual void SuppressAnimation(bool aSuppress) {}
+
+ /**
+ * Return size mode (minimized, maximized, normalized).
+ * Returns a value from nsSizeMode (see nsIWidgetListener.h)
+ */
+ virtual nsSizeMode SizeMode() = 0;
+
+ /**
+ * Ask whether the window is tiled.
+ */
+ virtual bool IsTiled() const = 0;
+
+ /**
+ * Ask wether the widget is fully occluded
+ */
+ virtual bool IsFullyOccluded() const = 0;
+
+ /**
+ * Enable or disable this Widget
+ *
+ * @param aState true to enable the Widget, false to disable it.
+ */
+ virtual void Enable(bool aState) = 0;
+
+ /**
+ * Ask whether the widget is enabled
+ */
+ virtual bool IsEnabled() const = 0;
+
+ /*
+ * Whether we should request activation of this widget's toplevel window.
+ */
+ enum class Raise {
+ No,
+ Yes,
+ };
+
+ /**
+ * Request activation of this window or give focus to this widget.
+ */
+ virtual void SetFocus(Raise, mozilla::dom::CallerType aCallerType) = 0;
+
+ /**
+ * Get this widget's outside dimensions relative to its parent widget. For
+ * popup widgets the returned rect is in screen coordinates and not
+ * relative to its parent widget.
+ *
+ * @return the x, y, width and height of this widget.
+ */
+ virtual LayoutDeviceIntRect GetBounds() = 0;
+
+ /**
+ * Get this widget's outside dimensions in device coordinates. This
+ * includes any title bar on the window.
+ *
+ * @return the x, y, width and height of this widget.
+ */
+ virtual LayoutDeviceIntRect GetScreenBounds() = 0;
+
+ /**
+ * Similar to GetScreenBounds except that this function will always
+ * get the size when the widget is in the nsSizeMode_Normal size mode
+ * even if the current size mode is not nsSizeMode_Normal.
+ * This method will fail if the size mode is not nsSizeMode_Normal and
+ * the platform doesn't have the ability.
+ * This method will always succeed if the current size mode is
+ * nsSizeMode_Normal.
+ *
+ * @param aRect On return it holds the x, y, width and height of
+ * this widget.
+ */
+ [[nodiscard]] virtual nsresult GetRestoredBounds(
+ LayoutDeviceIntRect& aRect) = 0;
+
+ /**
+ * Get this widget's client area bounds, if the window has a 3D border
+ * appearance this returns the area inside the border. The position is the
+ * position of the client area relative to the client area of the parent
+ * widget (for root widgets and popup widgets it is in screen coordinates).
+ *
+ * @return the x, y, width and height of the client area of this widget.
+ */
+ virtual LayoutDeviceIntRect GetClientBounds() = 0;
+
+ /**
+ * Sets the non-client area dimensions of the window. Pass -1 to restore
+ * the system default frame size for that border. Pass zero to remove
+ * a border, or pass a specific value adjust a border. Units are in
+ * pixels. (DPI dependent)
+ *
+ * Platform notes:
+ * Windows: shrinking top non-client height will remove application
+ * icon and window title text. Glass desktops will refuse to set
+ * dimensions between zero and size < system default.
+ */
+ virtual nsresult SetNonClientMargins(const LayoutDeviceIntMargin&) = 0;
+
+ /**
+ * Sets the region around the edges of the window that can be dragged to
+ * resize the window. All four sides of the window will get the same margin.
+ */
+ virtual void SetResizeMargin(mozilla::LayoutDeviceIntCoord aResizeMargin) = 0;
+ /**
+ * Get the client offset from the window origin.
+ *
+ * @return the x and y of the offset.
+ */
+ virtual LayoutDeviceIntPoint GetClientOffset() = 0;
+
+ /**
+ * Returns the slop from the screen edges in device pixels.
+ * @see Window.screenEdgeSlop{X,Y}
+ */
+ virtual LayoutDeviceIntPoint GetScreenEdgeSlop() { return {}; }
+
+ /**
+ * Equivalent to GetClientBounds but only returns the size.
+ */
+ virtual LayoutDeviceIntSize GetClientSize() {
+ // Depending on the backend, overloading this method may be useful if
+ // requesting the client offset is expensive.
+ return GetClientBounds().Size();
+ }
+
+ /**
+ * Set the background color for this widget
+ *
+ * @param aColor the new background color
+ *
+ */
+
+ virtual void SetBackgroundColor(const nscolor& aColor) {}
+
+ /**
+ * If a cursor type is currently cached locally for this widget, clear the
+ * cached cursor to force an update on the next SetCursor call.
+ */
+
+ virtual void ClearCachedCursor() = 0;
+
+ struct Cursor {
+ // The system cursor chosen by the page. This is used if there's no custom
+ // cursor, or if we fail to use the custom cursor in some way (if the image
+ // fails to load, for example).
+ nsCursor mDefaultCursor = eCursor_standard;
+ // May be null, to represent no custom cursor image.
+ nsCOMPtr<imgIContainer> mContainer;
+ uint32_t mHotspotX = 0;
+ uint32_t mHotspotY = 0;
+ mozilla::ImageResolution mResolution;
+
+ bool IsCustom() const { return !!mContainer; }
+
+ bool operator==(const Cursor& aOther) const {
+ return mDefaultCursor == aOther.mDefaultCursor &&
+ mContainer.get() == aOther.mContainer.get() &&
+ mHotspotX == aOther.mHotspotX && mHotspotY == aOther.mHotspotY &&
+ mResolution == aOther.mResolution;
+ }
+
+ bool operator!=(const Cursor& aOther) const { return !(*this == aOther); }
+ };
+
+ /**
+ * Sets the cursor for this widget.
+ */
+ virtual void SetCursor(const Cursor&) = 0;
+
+ static nsIntSize CustomCursorSize(const Cursor&);
+
+ /**
+ * Get the window type of this widget.
+ */
+ WindowType GetWindowType() const { return mWindowType; }
+
+ /**
+ * Set the transparency mode of the top-level window containing this widget.
+ * So, e.g., if you call this on the widget for an IFRAME, the top level
+ * browser window containing the IFRAME actually gets set. Be careful.
+ *
+ * This can fail if the platform doesn't support
+ * transparency/glass. By default widgets are not
+ * transparent. This will also fail if the toplevel window is not
+ * a Mozilla window, e.g., if the widget is in an embedded
+ * context.
+ *
+ * After transparency/glass has been enabled, the initial alpha channel
+ * value for all pixels is 1, i.e., opaque.
+ * If the window is resized then the alpha channel values for
+ * all pixels are reset to 1.
+ * Pixel RGB color values are already premultiplied with alpha channel values.
+ */
+ virtual void SetTransparencyMode(TransparencyMode aMode) = 0;
+
+ /**
+ * Get the transparency mode of the top-level window that contains this
+ * widget.
+ */
+ virtual TransparencyMode GetTransparencyMode() = 0;
+
+ /**
+ * Set the shadow style of the window.
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetWindowShadowStyle(mozilla::StyleWindowShadow aStyle) = 0;
+
+ /**
+ * Set the opacity of the window.
+ * Values need to be between 0.0f (invisible) and 1.0f (fully opaque).
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetWindowOpacity(float aOpacity) {}
+
+ /**
+ * Set the transform of the window. Values are in device pixels,
+ * the origin is the top left corner of the window.
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetWindowTransform(const mozilla::gfx::Matrix& aTransform) {}
+
+ /**
+ * Set the preferred color-scheme for the widget.
+ * Ignored on non-Mac platforms.
+ */
+ virtual void SetColorScheme(const mozilla::Maybe<mozilla::ColorScheme>&) {}
+
+ /**
+ * Set whether the window should ignore mouse events or not, and if it should
+ * not, what input margin should it use.
+ *
+ * This is only used on popup windows. The margin is only implemented on
+ * Linux.
+ */
+ struct InputRegion {
+ bool mFullyTransparent = false;
+ mozilla::LayoutDeviceIntCoord mMargin = 0;
+ };
+ virtual void SetInputRegion(const InputRegion&) {}
+
+ /*
+ * On macOS, this method shows or hides the pill button in the titlebar
+ * that's used to collapse the toolbar.
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetShowsToolbarButton(bool aShow) = 0;
+
+ /*
+ * On macOS, this method determines whether we tell cocoa that the window
+ * supports native full screen. If we do so, and another window is in
+ * native full screen, this window will also appear in native full screen.
+ *
+ * We generally only want to do this for primary application windows.
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetSupportsNativeFullscreen(bool aSupportsNativeFullscreen) = 0;
+
+ enum WindowAnimationType {
+ eGenericWindowAnimation,
+ eDocumentWindowAnimation
+ };
+
+ /**
+ * Sets the kind of top-level window animation this widget should have. On
+ * macOS, this causes a particular kind of animation to be shown when the
+ * window is first made visible.
+ *
+ * Ignored on child widgets and on non-Mac platforms.
+ */
+ virtual void SetWindowAnimationType(WindowAnimationType aType) = 0;
+
+ /**
+ * Specifies whether the window title should be drawn even if the window
+ * contents extend into the titlebar. Ignored on windows that don't draw
+ * in the titlebar. Only implemented on macOS.
+ */
+ virtual void SetDrawsTitle(bool aDrawTitle) {}
+
+ /**
+ * Hide window chrome (borders, buttons) for this widget.
+ *
+ */
+ virtual void HideWindowChrome(bool aShouldHide) = 0;
+
+ enum FullscreenTransitionStage {
+ eBeforeFullscreenToggle,
+ eAfterFullscreenToggle
+ };
+
+ /**
+ * Prepares for fullscreen transition and returns whether the widget
+ * supports fullscreen transition. If this method returns false,
+ * PerformFullscreenTransition() must never be called. Otherwise,
+ * caller should call that method twice with "before" and "after"
+ * stages respectively in order. In the latter case, this method may
+ * return some data via aData pointer. Caller must pass that data to
+ * PerformFullscreenTransition() if any, and caller is responsible
+ * for releasing that data.
+ */
+ virtual bool PrepareForFullscreenTransition(nsISupports** aData) = 0;
+
+ /**
+ * Performs fullscreen transition. This method returns immediately,
+ * and will post aCallback to the main thread when the transition
+ * finishes.
+ */
+ virtual void PerformFullscreenTransition(FullscreenTransitionStage aStage,
+ uint16_t aDuration,
+ nsISupports* aData,
+ nsIRunnable* aCallback) = 0;
+
+ /**
+ * Perform any actions needed after the fullscreen transition has ended.
+ */
+ virtual void CleanupFullscreenTransition() = 0;
+
+ /**
+ * Return the screen the widget is in, or null if we don't know.
+ */
+ virtual already_AddRefed<Screen> GetWidgetScreen() = 0;
+
+ /**
+ * Put the toplevel window into or out of fullscreen mode.
+ *
+ * @return NS_OK if the widget is setup properly for fullscreen and
+ * FullscreenChanged callback has been or will be called. If other
+ * value is returned, the caller should continue the change itself.
+ */
+ virtual nsresult MakeFullScreen(bool aFullScreen) = 0;
+
+ /**
+ * Same as MakeFullScreen, except that, on systems which natively
+ * support fullscreen transition, calling this method explicitly
+ * requests that behavior.
+ * It is currently only supported on macOS 10.7+.
+ */
+ virtual nsresult MakeFullScreenWithNativeTransition(bool aFullScreen) {
+ return MakeFullScreen(aFullScreen);
+ }
+
+ /**
+ * Invalidate a specified rect for a widget so that it will be repainted
+ * later.
+ */
+ virtual void Invalidate(const LayoutDeviceIntRect& aRect) = 0;
+
+ enum LayerManagerPersistence {
+ LAYER_MANAGER_CURRENT = 0,
+ LAYER_MANAGER_PERSISTENT
+ };
+
+ /**
+ * Return the widget's LayerManager. The layer tree for that LayerManager is
+ * what gets rendered to the widget.
+ *
+ * Note that this tries to create a renderer if it doesn't exist.
+ */
+ virtual WindowRenderer* GetWindowRenderer() = 0;
+
+ /**
+ * Returns whether there's an existing window renderer.
+ */
+ virtual bool HasWindowRenderer() const = 0;
+
+ /**
+ * Called before each layer manager transaction to allow any preparation
+ * for DrawWindowUnderlay/Overlay that needs to be on the main thread.
+ *
+ * Always called on the main thread.
+ */
+ virtual void PrepareWindowEffects() = 0;
+
+ /**
+ * Called on the main thread at the end of WebRender display list building.
+ */
+ virtual void AddWindowOverlayWebRenderCommands(
+ mozilla::layers::WebRenderBridgeChild* aWrBridge,
+ mozilla::wr::DisplayListBuilder& aBuilder,
+ mozilla::wr::IpcResourceUpdateQueue& aResources) {}
+
+ /**
+ * Called when Gecko knows which themed widgets exist in this window.
+ * The passed array contains an entry for every themed widget of the right
+ * type (currently only StyleAppearance::Toolbar) within the window, except
+ * for themed widgets which are transformed or have effects applied to them
+ * (e.g. CSS opacity or filters).
+ * This could sometimes be called during display list construction
+ * outside of painting.
+ * If called during painting, it will be called before we actually
+ * paint anything.
+ */
+ virtual void UpdateThemeGeometries(
+ const nsTArray<ThemeGeometry>& aThemeGeometries) = 0;
+
+ /**
+ * Informs the widget about the region of the window that is opaque.
+ *
+ * @param aOpaqueRegion the region of the window that is opaque.
+ */
+ virtual void UpdateOpaqueRegion(const LayoutDeviceIntRegion& aOpaqueRegion) {}
+
+ /**
+ * Informs the widget about the region of the window that is draggable.
+ */
+ virtual void UpdateWindowDraggingRegion(
+ const LayoutDeviceIntRegion& aRegion) {}
+
+ /**
+ * Tells the widget whether the given input block results in a swipe.
+ * Should be called in response to a WidgetWheelEvent that has
+ * mFlags.mCanTriggerSwipe set on it.
+ */
+ virtual void ReportSwipeStarted(uint64_t aInputBlockId, bool aStartSwipe) {}
+
+ /**
+ * Internal methods
+ */
+
+ //@{
+ virtual void AddChild(nsIWidget* aChild) = 0;
+ virtual void RemoveChild(nsIWidget* aChild) = 0;
+ virtual void* GetNativeData(uint32_t aDataType) = 0;
+ virtual void FreeNativeData(void* data, uint32_t aDataType) = 0; //~~~
+
+ //@}
+
+ /**
+ * Set the widget's title.
+ * Must be called after Create.
+ *
+ * @param aTitle string displayed as the title of the widget
+ */
+ virtual nsresult SetTitle(const nsAString& aTitle) = 0;
+
+ /**
+ * Set the widget's icon.
+ * Must be called after Create.
+ *
+ * @param aIconSpec string specifying the icon to use; convention is to
+ * pass a resource: URL from which a platform-dependent
+ * resource file name will be constructed
+ */
+ virtual void SetIcon(const nsAString& aIconSpec) = 0;
+
+ /**
+ * Return this widget's origin in screen coordinates.
+ *
+ * @return screen coordinates stored in the x,y members
+ */
+ virtual LayoutDeviceIntPoint WidgetToScreenOffset() = 0;
+
+ /**
+ * The same as WidgetToScreenOffset(), except in the case of
+ * PuppetWidget where this method omits the chrome offset.
+ */
+ virtual LayoutDeviceIntPoint TopLevelWidgetToScreenOffset() {
+ return WidgetToScreenOffset();
+ }
+
+ /**
+ * For a PuppetWidget, returns the transform from the coordinate
+ * space of the PuppetWidget to the coordinate space of the
+ * top-level native widget.
+ *
+ * Identity transform in other cases.
+ */
+ virtual mozilla::LayoutDeviceToLayoutDeviceMatrix4x4
+ WidgetToTopLevelWidgetTransform() {
+ return mozilla::LayoutDeviceToLayoutDeviceMatrix4x4();
+ }
+
+ mozilla::LayoutDeviceIntPoint WidgetToTopLevelWidgetOffset() {
+ return mozilla::LayoutDeviceIntPoint::Round(
+ WidgetToTopLevelWidgetTransform().TransformPoint(
+ mozilla::LayoutDevicePoint()));
+ }
+
+ /**
+ * Returns the margins that are applied to go from client sizes to window
+ * sizes (which includes window borders and titlebar).
+ * This method should work even when the window is not yet visible.
+ */
+ virtual LayoutDeviceIntMargin ClientToWindowMargin() { return {}; }
+
+ LayoutDeviceIntSize ClientToWindowSizeDifference();
+
+ /**
+ * Dispatches an event to the widget
+ */
+ virtual nsresult DispatchEvent(mozilla::WidgetGUIEvent* event,
+ nsEventStatus& aStatus) = 0;
+
+ /**
+ * Dispatches an event to APZ only.
+ * No-op in the child process.
+ */
+ virtual void DispatchEventToAPZOnly(mozilla::WidgetInputEvent* aEvent) = 0;
+
+ /*
+ * Dispatch a gecko event for this widget.
+ * Returns true if it's consumed. Otherwise, false.
+ */
+ virtual bool DispatchWindowEvent(mozilla::WidgetGUIEvent& event) = 0;
+
+ // A structure that groups the statuses from APZ dispatch and content
+ // dispatch.
+ struct ContentAndAPZEventStatus {
+ // Either of these may not be set if the event was not dispatched
+ // to APZ or to content.
+ nsEventStatus mApzStatus = nsEventStatus_eIgnore;
+ nsEventStatus mContentStatus = nsEventStatus_eIgnore;
+ };
+
+ /**
+ * Dispatches an event that must be handled by APZ first, when APZ is
+ * enabled. If invoked in the child process, it is forwarded to the
+ * parent process synchronously.
+ */
+ virtual ContentAndAPZEventStatus DispatchInputEvent(
+ mozilla::WidgetInputEvent* aEvent) = 0;
+
+ /**
+ * Confirm an APZ-aware event target. This should be used when APZ will
+ * not need a layers update to process the event.
+ */
+ virtual void SetConfirmedTargetAPZC(
+ uint64_t aInputBlockId,
+ const nsTArray<ScrollableLayerGuid>& aTargets) const = 0;
+
+ /**
+ * Returns true if APZ is in use, false otherwise.
+ */
+ virtual bool AsyncPanZoomEnabled() const = 0;
+
+ /**
+ */
+ virtual void SwipeFinished() = 0;
+
+ /**
+ * Enables the dropping of files to a widget.
+ */
+ virtual void EnableDragDrop(bool aEnable) = 0;
+ virtual nsresult AsyncEnableDragDrop(bool aEnable) = 0;
+
+ /**
+ * Classify the window for the window manager. Mostly for X11.
+ *
+ * @param xulWinType The window type. Characters other than [A-Za-z0-9_-] are
+ * converted to '_'. Anything before the first colon is
+ * assigned to name, anything after it to role. If there's
+ * no colon, assign the whole thing to both role and name.
+ *
+ * @param xulWinClass The window class. If set, overrides the normal value.
+ * Otherwise, the program class it used.
+ *
+ * @param xulWinName The window name. If set, overrides the value specified in
+ * window type. Otherwise, name from window type is used.
+ *
+ */
+ virtual void SetWindowClass(const nsAString& xulWinType,
+ const nsAString& xulWinClass,
+ const nsAString& xulWinName) = 0;
+
+ /**
+ * Enables/Disables system capture of any and all events that would cause a
+ * popup to be rolled up. aListener should be set to a non-null value for
+ * any popups that are not managed by the popup manager.
+ * @param aDoCapture true enables capture, false disables capture
+ *
+ */
+ virtual void CaptureRollupEvents(bool aDoCapture) = 0;
+
+ /**
+ * Bring this window to the user's attention. This is intended to be a more
+ * gentle notification than popping the window to the top or putting up an
+ * alert. See, for example, Win32 FlashWindow or the NotificationManager on
+ * the Mac. The notification should be suppressed if the window is already
+ * in the foreground and should be dismissed when the user brings this window
+ * to the foreground.
+ * @param aCycleCount Maximum number of times to animate the window per system
+ * conventions. If set to -1, cycles indefinitely until
+ * window is brought into the foreground.
+ */
+ [[nodiscard]] virtual nsresult GetAttention(int32_t aCycleCount) = 0;
+
+ /**
+ * Ask whether there user input events pending. All input events are
+ * included, including those not targeted at this nsIwidget instance.
+ */
+ virtual bool HasPendingInputEvent() = 0;
+
+ /**
+ * If set to true, the window will draw its contents into the titlebar
+ * instead of below it.
+ *
+ * Ignored on any platform that does not support it. Ignored by widgets that
+ * do not represent windows.
+ * May result in a resize event, so should only be called from places where
+ * reflow and painting is allowed.
+ *
+ * @param aState Whether drawing into the titlebar should be activated.
+ */
+ virtual void SetDrawsInTitlebar(bool aState) = 0;
+
+ /*
+ * Determine whether the widget shows a resize widget. If it does,
+ * aResizerRect returns the resizer's rect.
+ *
+ * Returns false on any platform that does not support it.
+ *
+ * @param aResizerRect The resizer's rect in device pixels.
+ * @return Whether a resize widget is shown.
+ */
+ virtual bool ShowsResizeIndicator(LayoutDeviceIntRect* aResizerRect) = 0;
+
+ // TODO: Make this an enum class with MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS or
+ // EnumSet class.
+ enum Modifiers : uint32_t {
+ NO_MODIFIERS = 0x00000000,
+ CAPS_LOCK = 0x00000001, // when CapsLock is active
+ NUM_LOCK = 0x00000002, // when NumLock is active
+ SHIFT_L = 0x00000100,
+ SHIFT_R = 0x00000200,
+ CTRL_L = 0x00000400,
+ CTRL_R = 0x00000800,
+ ALT_L = 0x00001000, // includes Option
+ ALT_R = 0x00002000,
+ COMMAND_L = 0x00004000,
+ COMMAND_R = 0x00008000,
+ HELP = 0x00010000,
+ ALTGRAPH = 0x00020000, // AltGr key on Windows. This emulates
+ // AltRight key behavior of keyboard
+ // layouts which maps AltGr to AltRight
+ // key.
+ FUNCTION = 0x00100000,
+ NUMERIC_KEY_PAD = 0x01000000 // when the key is coming from the keypad
+ };
+ /**
+ * Utility method intended for testing. Dispatches native key events
+ * to this widget to simulate the press and release of a key.
+ * @param aNativeKeyboardLayout a *platform-specific* constant.
+ * On Mac, this is the resource ID for a 'uchr' or 'kchr' resource.
+ * On Windows, it is converted to a hex string and passed to
+ * LoadKeyboardLayout, see
+ * http://msdn.microsoft.com/en-us/library/ms646305(VS.85).aspx
+ * @param aNativeKeyCode a *platform-specific* keycode.
+ * On Windows, this is the virtual key code.
+ * @param aModifiers some combination of the above 'Modifiers' flags;
+ * not all flags will apply to all platforms. Mac ignores the _R
+ * modifiers. Windows ignores COMMAND, NUMERIC_KEY_PAD, HELP and
+ * FUNCTION.
+ * @param aCharacters characters that the OS would decide to generate
+ * from the event. On Windows, this is the charCode passed by
+ * WM_CHAR.
+ * @param aUnmodifiedCharacters characters that the OS would decide
+ * to generate from the event if modifier keys (other than shift)
+ * were assumed inactive. Needed on Mac, ignored on Windows.
+ * @param aObserver the observer that will get notified once the events
+ * have been dispatched.
+ * @return NS_ERROR_NOT_AVAILABLE to indicate that the keyboard
+ * layout is not supported and the event was not fired
+ */
+ virtual nsresult SynthesizeNativeKeyEvent(
+ int32_t aNativeKeyboardLayout, int32_t aNativeKeyCode,
+ uint32_t aModifierFlags, const nsAString& aCharacters,
+ const nsAString& aUnmodifiedCharacters, nsIObserver* aObserver) = 0;
+
+ /**
+ * Utility method intended for testing. Dispatches native mouse events
+ * may even move the mouse cursor. On Mac the events are guaranteed to
+ * be sent to the window containing this widget, but on Windows they'll go
+ * to whatever's topmost on the screen at that position, so for
+ * cross-platform testing ensure that your window is at the top of the
+ * z-order.
+ * @param aPoint screen location of the mouse, in device
+ * pixels, with origin at the top left
+ * @param aNativeMessage abstract native message.
+ * @param aButton Mouse button defined by DOM UI Events.
+ * @param aModifierFlags Some values of nsIWidget::Modifiers.
+ * FYI: On Windows, Android and Headless widget on all
+ * platroms, this hasn't been handled yet.
+ * @param aObserver the observer that will get notified once the events
+ * have been dispatched.
+ */
+ enum class NativeMouseMessage : uint32_t {
+ ButtonDown, // button down
+ ButtonUp, // button up
+ Move, // mouse cursor move
+ EnterWindow, // mouse cursor comes into a window
+ LeaveWindow, // mouse cursor leaves from a window
+ };
+ virtual nsresult SynthesizeNativeMouseEvent(
+ LayoutDeviceIntPoint aPoint, NativeMouseMessage aNativeMessage,
+ mozilla::MouseButton aButton, nsIWidget::Modifiers aModifierFlags,
+ nsIObserver* aObserver) = 0;
+
+ /**
+ * A shortcut to SynthesizeNativeMouseEvent, abstracting away the native
+ * message. aPoint is location in device pixels to which the mouse pointer
+ * moves to.
+ * @param aObserver the observer that will get notified once the events
+ * have been dispatched.
+ */
+ virtual nsresult SynthesizeNativeMouseMove(LayoutDeviceIntPoint aPoint,
+ nsIObserver* aObserver) = 0;
+
+ /**
+ * Utility method intended for testing. Dispatching native mouse scroll
+ * events may move the mouse cursor.
+ *
+ * @param aPoint Mouse cursor position in screen coordinates.
+ * In device pixels, the origin at the top left of
+ * the primary display.
+ * @param aNativeMessage Platform native message.
+ * @param aDeltaX The delta value for X direction. If the native
+ * message doesn't indicate X direction scrolling,
+ * this may be ignored.
+ * @param aDeltaY The delta value for Y direction. If the native
+ * message doesn't indicate Y direction scrolling,
+ * this may be ignored.
+ * @param aDeltaZ The delta value for Z direction. If the native
+ * message doesn't indicate Z direction scrolling,
+ * this may be ignored.
+ * @param aModifierFlags Must be values of Modifiers, or zero.
+ * @param aAdditionalFlags See nsIDOMWidnowUtils' consts and their
+ * document.
+ * @param aObserver The observer that will get notified once the
+ * events have been dispatched.
+ */
+ virtual nsresult SynthesizeNativeMouseScrollEvent(
+ LayoutDeviceIntPoint aPoint, uint32_t aNativeMessage, double aDeltaX,
+ double aDeltaY, double aDeltaZ, uint32_t aModifierFlags,
+ uint32_t aAdditionalFlags, nsIObserver* aObserver) = 0;
+
+ /*
+ * TouchPointerState states for SynthesizeNativeTouchPoint. Match
+ * touch states in nsIDOMWindowUtils.idl.
+ */
+ enum TouchPointerState {
+ // The pointer is in a hover state above the digitizer
+ TOUCH_HOVER = (1 << 0),
+ // The pointer is in contact with the digitizer
+ TOUCH_CONTACT = (1 << 1),
+ // The pointer has been removed from the digitizer detection area
+ TOUCH_REMOVE = (1 << 2),
+ // The pointer has been canceled. Will cancel any pending os level
+ // gestures that would triggered as a result of completion of the
+ // input sequence. This may not cancel moz platform related events
+ // that might get tirggered by input already delivered.
+ TOUCH_CANCEL = (1 << 3),
+
+ // ALL_BITS used for validity checking during IPC serialization
+ ALL_BITS = (1 << 4) - 1
+ };
+ /*
+ * TouchpadGesturePhase states for SynthesizeNativeTouchPadPinch and
+ * SynthesizeNativeTouchpadPan. Match phase states in nsIDOMWindowUtils.idl.
+ */
+ enum TouchpadGesturePhase {
+ PHASE_BEGIN = 0,
+ PHASE_UPDATE = 1,
+ PHASE_END = 2
+ };
+ /*
+ * Create a new or update an existing touch pointer on the digitizer.
+ * To trigger os level gestures, individual touch points should
+ * transition through a complete set of touch states which should be
+ * sent as individual messages.
+ *
+ * @param aPointerId The touch point id to create or update.
+ * @param aPointerState one or more of the touch states listed above
+ * @param aPoint coords of this event
+ * @param aPressure 0.0 -> 1.0 float val indicating pressure
+ * @param aOrientation 0 -> 359 degree value indicating the
+ * orientation of the pointer. Use 90 for normal taps.
+ * @param aObserver The observer that will get notified once the events
+ * have been dispatched.
+ */
+ virtual nsresult SynthesizeNativeTouchPoint(uint32_t aPointerId,
+ TouchPointerState aPointerState,
+ LayoutDeviceIntPoint aPoint,
+ double aPointerPressure,
+ uint32_t aPointerOrientation,
+ nsIObserver* aObserver) = 0;
+ /*
+ * See nsIDOMWindowUtils.sendNativeTouchpadPinch().
+ */
+ virtual nsresult SynthesizeNativeTouchPadPinch(
+ TouchpadGesturePhase aEventPhase, float aScale,
+ LayoutDeviceIntPoint aPoint, int32_t aModifierFlags) = 0;
+
+ /*
+ * Helper for simulating a simple tap event with one touch point. When
+ * aLongTap is true, simulates a native long tap with a duration equal to
+ * ui.click_hold_context_menus.delay. This pref is compatible with the
+ * apzc long tap duration. Defaults to 1.5 seconds.
+ * @param aObserver The observer that will get notified once the events
+ * have been dispatched.
+ */
+ virtual nsresult SynthesizeNativeTouchTap(LayoutDeviceIntPoint aPoint,
+ bool aLongTap,
+ nsIObserver* aObserver);
+
+ virtual nsresult SynthesizeNativePenInput(uint32_t aPointerId,
+ TouchPointerState aPointerState,
+ LayoutDeviceIntPoint aPoint,
+ double aPressure,
+ uint32_t aRotation, int32_t aTiltX,
+ int32_t aTiltY, int32_t aButton,
+ nsIObserver* aObserver) = 0;
+
+ /*
+ * Cancels all active simulated touch input points and pending long taps.
+ * Native widgets should track existing points such that they can clear the
+ * digitizer state when this call is made.
+ * @param aObserver The observer that will get notified once the touch
+ * sequence has been cleared.
+ */
+ virtual nsresult ClearNativeTouchSequence(nsIObserver* aObserver);
+
+ /*
+ * Send a native event as if the user double tapped the touchpad with two
+ * fingers.
+ */
+ virtual nsresult SynthesizeNativeTouchpadDoubleTap(
+ LayoutDeviceIntPoint aPoint, uint32_t aModifierFlags) = 0;
+
+ /*
+ * See nsIDOMWindowUtils.sendNativeTouchpadPan().
+ */
+ virtual nsresult SynthesizeNativeTouchpadPan(TouchpadGesturePhase aEventPhase,
+ LayoutDeviceIntPoint aPoint,
+ double aDeltaX, double aDeltaY,
+ int32_t aModifierFlags,
+ nsIObserver* aObserver) = 0;
+
+ virtual void StartAsyncScrollbarDrag(
+ const AsyncDragMetrics& aDragMetrics) = 0;
+
+ /**
+ * Notify APZ to start autoscrolling.
+ * @param aAnchorLocation the location of the autoscroll anchor
+ * @param aGuid identifies the scroll frame to be autoscrolled
+ * @return true if APZ has been successfully notified
+ */
+ virtual bool StartAsyncAutoscroll(const ScreenPoint& aAnchorLocation,
+ const ScrollableLayerGuid& aGuid) = 0;
+
+ /**
+ * Notify APZ to stop autoscrolling.
+ * @param aGuid identifies the scroll frame which is being autoscrolled.
+ */
+ virtual void StopAsyncAutoscroll(const ScrollableLayerGuid& aGuid) = 0;
+
+ virtual LayersId GetRootLayerTreeId() = 0;
+
+ // If this widget supports out-of-process compositing, it can override
+ // this method to provide additional information to the compositor.
+ virtual void GetCompositorWidgetInitData(
+ mozilla::widget::CompositorWidgetInitData* aInitData) {}
+
+ /**
+ * Setter/Getter of the system font setting for testing.
+ */
+ virtual nsresult SetSystemFont(const nsCString& aFontName) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+ }
+ virtual nsresult GetSystemFont(nsCString& aFontName) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+ }
+
+ /**
+ * Wayland specific routines.
+ */
+ virtual LayoutDeviceIntSize GetMoveToRectPopupSize() const {
+ NS_WARNING("GetLayoutPopupRect implemented only for wayland");
+ return LayoutDeviceIntSize();
+ }
+
+ /**
+ * If this widget uses native pointer lock instead of warp-to-center
+ * (currently only GTK on Wayland), these methods provide access to that
+ * functionality.
+ */
+ virtual void SetNativePointerLockCenter(
+ const LayoutDeviceIntPoint& aLockCenter) {}
+ virtual void LockNativePointer() {}
+ virtual void UnlockNativePointer() {}
+
+ /*
+ * Get safe area insets except to cutout.
+ * See https://drafts.csswg.org/css-env-1/#safe-area-insets.
+ */
+ virtual mozilla::ScreenIntMargin GetSafeAreaInsets() const {
+ return mozilla::ScreenIntMargin();
+ }
+
+ private:
+ class LongTapInfo {
+ public:
+ LongTapInfo(int32_t aPointerId, LayoutDeviceIntPoint& aPoint,
+ mozilla::TimeDuration aDuration, nsIObserver* aObserver)
+ : mPointerId(aPointerId),
+ mPosition(aPoint),
+ mDuration(aDuration),
+ mObserver(aObserver),
+ mStamp(mozilla::TimeStamp::Now()) {}
+
+ int32_t mPointerId;
+ LayoutDeviceIntPoint mPosition;
+ mozilla::TimeDuration mDuration;
+ nsCOMPtr<nsIObserver> mObserver;
+ mozilla::TimeStamp mStamp;
+ };
+
+ static void OnLongTapTimerCallback(nsITimer* aTimer, void* aClosure);
+
+ static already_AddRefed<nsIBidiKeyboard> CreateBidiKeyboardContentProcess();
+ static already_AddRefed<nsIBidiKeyboard> CreateBidiKeyboardInner();
+
+ mozilla::UniquePtr<LongTapInfo> mLongTapTouchPoint;
+ nsCOMPtr<nsITimer> mLongTapTimer;
+ static int32_t sPointerIdCounter;
+
+ public:
+ /**
+ * If key events have not been handled by content or XBL handlers, they can
+ * be offered to the system (for custom application shortcuts set in system
+ * preferences, for example).
+ */
+ virtual void PostHandleKeyEvent(mozilla::WidgetKeyboardEvent* aEvent);
+
+ /**
+ * Activates a native menu item at the position specified by the index
+ * string. The index string is a string of positive integers separated
+ * by the "|" (pipe) character. The last integer in the string represents
+ * the item index in a submenu located using the integers preceding it.
+ *
+ * Example: 1|0|4
+ * In this string, the first integer represents the top-level submenu
+ * in the native menu bar. Since the integer is 1, it is the second submeu
+ * in the native menu bar. Within that, the first item (index 0) is a
+ * submenu, and we want to activate the 5th item within that submenu.
+ */
+ virtual nsresult ActivateNativeMenuItemAt(const nsAString& indexString) = 0;
+
+ /**
+ * This is used for native menu system testing.
+ *
+ * Updates a native menu at the position specified by the index string.
+ * The index string is a string of positive integers separated by the "|"
+ * (pipe) character.
+ *
+ * Example: 1|0|4
+ * In this string, the first integer represents the top-level submenu
+ * in the native menu bar. Since the integer is 1, it is the second submeu
+ * in the native menu bar. Within that, the first item (index 0) is a
+ * submenu, and we want to update submenu at index 4 within that submenu.
+ *
+ * If this is called with an empty string it forces a full reload of the
+ * menu system.
+ */
+ virtual nsresult ForceUpdateNativeMenuAt(const nsAString& indexString) = 0;
+
+ /**
+ * This is used for testing macOS service menu code.
+ *
+ * @param aResult - the current text selection. Is empty if no selection.
+ * @return nsresult - whether or not aResult was assigned the selected text.
+ */
+ [[nodiscard]] virtual nsresult GetSelectionAsPlaintext(nsAString& aResult) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+ }
+
+ /**
+ * Notify IME of the specified notification.
+ *
+ * @return If the notification is mouse button event and it's consumed by
+ * IME, this returns NS_SUCCESS_EVENT_CONSUMED.
+ */
+ virtual nsresult NotifyIME(const IMENotification& aIMENotification) = 0;
+
+ /**
+ * MaybeDispatchInitialFocusEvent will dispatch a focus event after creation
+ * of the widget, in the event that we were not able to observe and respond to
+ * the initial focus event. This is necessary for the early skeleton UI
+ * window, which is displayed and receives its initial focus event before we
+ * can actually respond to it.
+ */
+ virtual void MaybeDispatchInitialFocusEvent() {}
+
+ /*
+ * Notifies the input context changes.
+ */
+ virtual void SetInputContext(const InputContext& aContext,
+ const InputContextAction& aAction) = 0;
+
+ /*
+ * Get current input context.
+ */
+ virtual InputContext GetInputContext() = 0;
+
+ /**
+ * Get native IME context. This is different from GetNativeData() with
+ * NS_RAW_NATIVE_IME_CONTEXT, the result is unique even if in a remote
+ * process.
+ */
+ virtual NativeIMEContext GetNativeIMEContext() = 0;
+
+ /*
+ * Given a WidgetKeyboardEvent, this method synthesizes a corresponding
+ * native (OS-level) event for it. This method allows tests to simulate
+ * keystrokes that trigger native key bindings (which require a native
+ * event).
+ */
+ [[nodiscard]] virtual nsresult AttachNativeKeyEvent(
+ mozilla::WidgetKeyboardEvent& aEvent) = 0;
+
+ /**
+ * Retrieve edit commands when the key combination of aEvent is used
+ * in platform native applications.
+ */
+ MOZ_CAN_RUN_SCRIPT virtual bool GetEditCommands(
+ mozilla::NativeKeyBindingsType aType,
+ const mozilla::WidgetKeyboardEvent& aEvent,
+ nsTArray<mozilla::CommandInt>& aCommands);
+
+ /*
+ * Retrieves a reference to notification requests of IME. Note that the
+ * reference is valid while the nsIWidget instance is alive. So, if you
+ * need to store the reference for a long time, you need to grab the widget
+ * instance too.
+ */
+ const IMENotificationRequests& IMENotificationRequestsRef();
+
+ /*
+ * Call this method when a dialog is opened which has a default button.
+ * The button's rectangle should be supplied in aButtonRect.
+ */
+ [[nodiscard]] virtual nsresult OnDefaultButtonLoaded(
+ const LayoutDeviceIntRect& aButtonRect) = 0;
+
+ /**
+ * Return true if this process shouldn't use platform widgets, and
+ * so should use PuppetWidgets instead. If this returns true, the
+ * result of creating and using a platform widget is undefined,
+ * and likely to end in crashes or other buggy behavior.
+ */
+ static bool UsePuppetWidgets() { return XRE_IsContentProcess(); }
+
+ static already_AddRefed<nsIWidget> CreateTopLevelWindow();
+
+ static already_AddRefed<nsIWidget> CreateChildWindow();
+
+ /**
+ * Allocate and return a "puppet widget" that doesn't directly
+ * correlate to a platform widget; platform events and data must
+ * be fed to it. Currently used in content processes. NULL is
+ * returned if puppet widgets aren't supported in this build
+ * config, on this platform, or for this process type.
+ *
+ * This function is called "Create" to match CreateInstance().
+ * The returned widget must still be nsIWidget::Create()d.
+ */
+ static already_AddRefed<nsIWidget> CreatePuppetWidget(
+ BrowserChild* aBrowserChild);
+
+ static already_AddRefed<nsIWidget> CreateHeadlessWidget();
+
+ /**
+ * Reparent this widget's native widget.
+ * @param aNewParent the native widget of aNewParent is the new native
+ * parent widget
+ */
+ virtual void ReparentNativeWidget(nsIWidget* aNewParent) = 0;
+
+ /**
+ * Return true if widget has it's own GL context
+ */
+ virtual bool HasGLContext() { return false; }
+
+ /**
+ * Returns true to indicate that this widget paints an opaque background
+ * that we want to be visible under the page, so layout should not force
+ * a default background.
+ */
+ virtual bool WidgetPaintsBackground() { return false; }
+
+ virtual bool NeedsPaint() { return IsVisible() && !GetBounds().IsEmpty(); }
+
+ /**
+ * Get the natural bounds of this widget. This method is only
+ * meaningful for widgets for which Gecko implements screen
+ * rotation natively. When this is the case, GetBounds() returns
+ * the widget bounds taking rotation into account, and
+ * GetNaturalBounds() returns the bounds *not* taking rotation
+ * into account.
+ *
+ * No code outside of the composition pipeline should know or care
+ * about this. If you're not an agent of the compositor, you
+ * probably shouldn't call this method.
+ */
+ virtual LayoutDeviceIntRect GetNaturalBounds() { return GetBounds(); }
+
+ /**
+ * Set size constraints on the window size such that it is never less than
+ * the specified minimum size and never larger than the specified maximum
+ * size. The size constraints are sizes of the outer rectangle including
+ * the window frame and title bar. Use 0 for an unconstrained minimum size
+ * and NS_MAXSIZE for an unconstrained maximum size. Note that this method
+ * does not necessarily change the size of a window to conform to this size,
+ * thus Resize should be called afterwards.
+ *
+ * @param aConstraints: the size constraints in device pixels
+ */
+ virtual void SetSizeConstraints(const SizeConstraints& aConstraints) = 0;
+
+ /**
+ * Return the size constraints currently observed by the widget.
+ *
+ * @return the constraints in device pixels
+ */
+ virtual const SizeConstraints GetSizeConstraints() = 0;
+
+ /**
+ * Apply the current size constraints to the given size.
+ *
+ * @param aWidth width to constrain
+ * @param aHeight height to constrain
+ */
+ virtual void ConstrainSize(int32_t* aWidth, int32_t* aHeight) = 0;
+
+ /**
+ * If this is owned by a BrowserChild, return that. Otherwise return
+ * null.
+ */
+ virtual BrowserChild* GetOwningBrowserChild() { return nullptr; }
+
+ /**
+ * If this isn't directly compositing to its window surface,
+ * return the compositor which is doing that on our behalf.
+ */
+ virtual CompositorBridgeChild* GetRemoteRenderer() { return nullptr; }
+
+ /**
+ * Clear WebRender resources
+ */
+ virtual void ClearCachedWebrenderResources() {}
+
+ /**
+ * Clear WebRender animation resources
+ */
+ virtual void ClearWebrenderAnimationResources() {}
+
+ /**
+ * Request fast snapshot at RenderCompositor of WebRender.
+ * Since readback of Windows DirectComposition is very slow.
+ */
+ virtual bool SetNeedFastSnaphot() { return false; }
+
+ /**
+ * If this widget has its own vsync dispatcher, return it, otherwise return
+ * nullptr. An example of such a local vsync dispatcher would be Wayland frame
+ * callbacks.
+ */
+ virtual RefPtr<mozilla::VsyncDispatcher> GetVsyncDispatcher();
+
+ /**
+ * Returns true if the widget requires synchronous repaints on resize,
+ * false otherwise.
+ */
+ virtual bool SynchronouslyRepaintOnResize() { return true; }
+
+ /**
+ * Some platforms (only cocoa right now) round widget coordinates to the
+ * nearest even pixels (see bug 892994), this function allows us to
+ * determine how widget coordinates will be rounded.
+ */
+ virtual int32_t RoundsWidgetCoordinatesTo() { return 1; }
+
+ virtual void UpdateZoomConstraints(
+ const uint32_t& aPresShellId, const ScrollableLayerGuid::ViewID& aViewId,
+ const mozilla::Maybe<ZoomConstraints>& aConstraints){};
+
+ /**
+ * GetTextEventDispatcher() returns TextEventDispatcher belonging to the
+ * widget. Note that this never returns nullptr.
+ */
+ virtual TextEventDispatcher* GetTextEventDispatcher() = 0;
+
+ /**
+ * GetNativeTextEventDispatcherListener() returns a
+ * TextEventDispatcherListener instance which is used when the widget
+ * instance handles native IME and/or keyboard events.
+ */
+ virtual TextEventDispatcherListener*
+ GetNativeTextEventDispatcherListener() = 0;
+
+ virtual void ZoomToRect(const uint32_t& aPresShellId,
+ const ScrollableLayerGuid::ViewID& aViewId,
+ const CSSRect& aRect, const uint32_t& aFlags) = 0;
+
+ /**
+ * LookUpDictionary shows the dictionary for the word around current point.
+ *
+ * @param aText the word to look up dictiorary.
+ * @param aFontRangeArray text decoration of aText
+ * @param aIsVertical true if the word is vertical layout
+ * @param aPoint top-left point of aText
+ */
+ virtual void LookUpDictionary(
+ const nsAString& aText,
+ const nsTArray<mozilla::FontRange>& aFontRangeArray,
+ const bool aIsVertical, const LayoutDeviceIntPoint& aPoint) {}
+
+ virtual void RequestFxrOutput() {
+ MOZ_ASSERT(false, "This function should only execute in Windows");
+ }
+
+#if defined(MOZ_WIDGET_ANDROID)
+ /**
+ * RecvToolbarAnimatorMessageFromCompositor receive message from compositor
+ * thread.
+ *
+ * @param aMessage message being sent to Android UI thread.
+ */
+ virtual void RecvToolbarAnimatorMessageFromCompositor(int32_t aMessage) = 0;
+
+ /**
+ * UpdateRootFrameMetrics steady state frame metrics send from compositor
+ * thread
+ *
+ * @param aScrollOffset page scroll offset value in screen pixels.
+ * @param aZoom current page zoom.
+ */
+ virtual void UpdateRootFrameMetrics(const ScreenPoint& aScrollOffset,
+ const CSSToScreenScale& aZoom) = 0;
+
+ /**
+ * RecvScreenPixels Buffer containing the pixel from the frame buffer. Used
+ * for android robocop tests.
+ *
+ * @param aMem shared memory containing the frame buffer pixels.
+ * @param aSize size of the buffer in screen pixels.
+ */
+ virtual void RecvScreenPixels(mozilla::ipc::Shmem&& aMem,
+ const ScreenIntSize& aSize,
+ bool aNeedsYFlip) = 0;
+
+ virtual void UpdateDynamicToolbarMaxHeight(mozilla::ScreenIntCoord aHeight) {}
+ virtual mozilla::ScreenIntCoord GetDynamicToolbarMaxHeight() const {
+ return 0;
+ }
+#endif
+
+ static already_AddRefed<nsIBidiKeyboard> CreateBidiKeyboard();
+
+ /**
+ * Like GetDefaultScale, but taking into account only the system settings
+ * and ignoring Gecko preferences.
+ */
+ virtual double GetDefaultScaleInternal() { return 1.0; }
+
+ using WindowButtonType = mozilla::WindowButtonType;
+
+ /**
+ * Layout uses this to alert the widget to the client rect representing
+ * the window maximize button. An empty rect indicates there is no
+ * maximize button (for example, in fullscreen). This is only implemented
+ * on Windows.
+ */
+ virtual void SetWindowButtonRect(WindowButtonType aButtonType,
+ const LayoutDeviceIntRect& aClientRect) {}
+
+#ifdef DEBUG
+ virtual nsresult SetHiDPIMode(bool aHiDPI) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+ }
+ virtual nsresult RestoreHiDPIMode() { return NS_ERROR_NOT_IMPLEMENTED; }
+#endif
+
+ protected:
+ // keep the list of children. We also keep track of our siblings.
+ // The ownership model is as follows: parent holds a strong ref to
+ // the first element of the list, and each element holds a strong
+ // ref to the next element in the list. The prevsibling and
+ // lastchild pointers are weak, which is fine as long as they are
+ // maintained properly.
+ nsCOMPtr<nsIWidget> mFirstChild;
+ nsIWidget* MOZ_NON_OWNING_REF mLastChild;
+ nsCOMPtr<nsIWidget> mNextSibling;
+ nsIWidget* MOZ_NON_OWNING_REF mPrevSibling;
+ // When Destroy() is called, the sub class should set this true.
+ bool mOnDestroyCalled;
+ WindowType mWindowType;
+ int32_t mZIndex;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsIWidget, NS_IWIDGET_IID)
+
+#endif // nsIWidget_h__