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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=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 */
#ifndef nsSliderFrame_h__
#define nsSliderFrame_h__
#include "mozilla/Attributes.h"
#include "nsContainerFrame.h"
#include "nsRepeatService.h"
#include "nsAtom.h"
#include "nsCOMPtr.h"
#include "nsITimer.h"
#include "nsIDOMEventListener.h"
class nsITimer;
class nsScrollbarFrame;
class nsSliderFrame;
namespace mozilla {
class nsDisplaySliderMarks;
class PresShell;
class ScrollContainerFrame;
} // namespace mozilla
nsIFrame* NS_NewSliderFrame(mozilla::PresShell* aPresShell,
mozilla::ComputedStyle* aStyle);
class nsSliderMediator final : public nsIDOMEventListener {
nsSliderFrame* mSlider;
explicit nsSliderMediator(nsSliderFrame* aSlider) { mSlider = aSlider; }
void SetSlider(nsSliderFrame* aSlider) { mSlider = aSlider; }
virtual ~nsSliderMediator() = default;
class nsSliderFrame final : public nsContainerFrame {
friend class nsSliderMediator;
friend class mozilla::nsDisplaySliderMarks;
explicit nsSliderFrame(ComputedStyle* aStyle, nsPresContext* aPresContext);
virtual ~nsSliderFrame();
// Get the point associated with this event. Returns true if a single valid
// point was found. Otherwise false.
bool GetEventPoint(mozilla::WidgetGUIEvent* aEvent, nsPoint& aPoint);
// Gets the event coordinates relative to the widget associated with this
// frame. Return true if a single valid point was found.
bool GetEventPoint(mozilla::WidgetGUIEvent* aEvent,
mozilla::LayoutDeviceIntPoint& aPoint);
nsresult GetFrameName(nsAString& aResult) const override {
return MakeFrameName(u"SliderFrame"_ns, aResult);
void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
// nsIFrame overrides
void Destroy(DestroyContext&) override;
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override;
void BuildDisplayListForThumb(nsDisplayListBuilder* aBuilder,
nsIFrame* aThumb,
const nsDisplayListSet& aLists);
nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
int32_t aModType) override;
void Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
nsresult HandleEvent(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus) override;
// nsContainerFrame overrides
void SetInitialChildList(ChildListID aListID,
nsFrameList&& aChildList) override;
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override;
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override;
void RemoveFrame(DestroyContext&, ChildListID, nsIFrame*) override;
nsresult StartDrag(mozilla::dom::Event* aEvent);
nsresult StopDrag();
void StartAPZDrag(mozilla::WidgetGUIEvent* aEvent);
static int32_t GetCurrentPosition(nsIContent* content);
static int32_t GetMinPosition(nsIContent* content);
static int32_t GetMaxPosition(nsIContent* content);
static int32_t GetIncrement(nsIContent* content);
static int32_t GetPageIncrement(nsIContent* content);
static int32_t GetIntegerAttribute(nsIContent* content, nsAtom* atom,
int32_t defaultValue);
NS_IMETHOD HandlePress(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus) override;
NS_IMETHOD HandleMultiplePress(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus,
bool aControlHeld) override {
return NS_OK;
NS_IMETHOD HandleDrag(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus) override {
return NS_OK;
NS_IMETHOD HandleRelease(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus) override;
// Return the ratio the scrollbar thumb should move in proportion to the
// scrolled frame.
float GetThumbRatio() const;
// Notify the slider frame that an async scrollbar drag was started on the
// APZ side without consulting the main thread. The block id is the APZ
// input block id of the mousedown that started the drag.
void AsyncScrollbarDragInitiated(uint64_t aDragBlockId);
// Notify the slider frame that an async scrollbar drag requested in
// StartAPZDrag() was rejected by APZ, and the slider frame should
// fall back to main-thread dragging.
void AsyncScrollbarDragRejected();
bool OnlySystemGroupDispatch(mozilla::EventMessage aMessage) const override;
// Returns the associated scroll container frame that contains this slider if
// any.
mozilla::ScrollContainerFrame* GetScrollContainerFrame();
bool GetScrollToClick();
nsScrollbarFrame* Scrollbar();
bool ShouldScrollForEvent(mozilla::WidgetGUIEvent* aEvent);
bool ShouldScrollToClickForEvent(mozilla::WidgetGUIEvent* aEvent);
bool IsEventOverThumb(mozilla::WidgetGUIEvent* aEvent);
void PageUpDown(nscoord change);
void SetCurrentThumbPosition(nsIContent* aScrollbar, nscoord aNewPos,
bool aIsSmooth, bool aMaySnap);
void SetCurrentPosition(nsIContent* aScrollbar, int32_t aNewPos,
bool aIsSmooth);
void SetCurrentPositionInternal(nsIContent* aScrollbar, int32_t pos,
bool aIsSmooth);
void CurrentPositionChanged();
void DragThumb(bool aGrabMouseEvents);
void AddListener();
void RemoveListener();
bool isDraggingThumb() const;
void SuppressDisplayport();
void UnsuppressDisplayport();
void StartRepeat() {
nsRepeatService::GetInstance()->Start(Notify, this, mContent->OwnerDoc(),
void StopRepeat() {
nsRepeatService::GetInstance()->Stop(Notify, this);
mCurrentClickHoldDestination = Nothing();
void Notify();
static void Notify(void* aData) {
void PageScroll(bool aClickAndHold);
void SetupDrag(mozilla::WidgetGUIEvent* aEvent, nsIFrame* aThumbFrame,
nscoord aPos, bool aIsHorizontal);
nsPoint mDestinationPoint;
// If we are in a scrollbar track click-and-hold, this is populated with
// the destination of the scroll started at the most recent tick of the
// repeat timer.
Maybe<nsPoint> mCurrentClickHoldDestination;
RefPtr<nsSliderMediator> mMediator;
float mRatio;
nscoord mDragStart;
nscoord mThumbStart;
int32_t mCurPos;
nscoord mRepeatDirection;
bool mDragFinished;
// true if an attribute change has been caused by the user manipulating the
// slider. This allows notifications to tell how a slider's current position
// was changed.
bool mUserChanged;
// true if we've handed off the scrolling to APZ. This means that we should
// ignore scrolling events as the position will be updated by APZ. If we were
// to process these events then the scroll position update would conflict
// causing the scroll position to jump.
bool mScrollingWithAPZ;
// true if displayport suppression is active, for more performant
// scrollbar-dragging behaviour.
bool mSuppressionActive;
// If APZ initiated a scrollbar drag without main-thread involvement, it
// notifies us and this variable stores the input block id of the APZ input
// block that started the drag. This lets us handle the corresponding
// mousedown event properly, if it arrives after the scroll position has
// been shifted due to async scrollbar drag.
Maybe<uint64_t> mAPZDragInitiated;
nscoord mThumbMinLength;
static bool gMiddlePref;
}; // class nsSliderFrame