mirror of
https://gitlab.winehq.org/wine/wine-gecko.git
synced 2024-09-13 09:24:08 -07:00
609fe6b9c4
Backed out changeset 6b53305f1c42 (bug 967844) Backed out changeset dff3eb181f33 (bug 967844) Backed out changeset 4d4b03442eaf (bug 967844)
346 lines
14 KiB
C++
346 lines
14 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* 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/. */
|
|
|
|
/*
|
|
* interface that provides scroll APIs implemented by scrollable frames
|
|
*/
|
|
|
|
#ifndef nsIScrollFrame_h___
|
|
#define nsIScrollFrame_h___
|
|
|
|
#include "nsCoord.h"
|
|
#include "ScrollbarStyles.h"
|
|
#include "mozilla/gfx/Point.h"
|
|
#include "nsIScrollbarMediator.h"
|
|
#include "Units.h"
|
|
|
|
#define NS_DEFAULT_VERTICAL_SCROLL_DISTANCE 3
|
|
#define NS_DEFAULT_HORIZONTAL_SCROLL_DISTANCE 5
|
|
|
|
class nsBoxLayoutState;
|
|
class nsIScrollPositionListener;
|
|
class nsIFrame;
|
|
class nsPresContext;
|
|
class nsIContent;
|
|
class nsRenderingContext;
|
|
class nsIAtom;
|
|
|
|
/**
|
|
* Interface for frames that are scrollable. This interface exposes
|
|
* APIs for examining scroll state, observing changes to scroll state,
|
|
* and triggering scrolling.
|
|
*/
|
|
class nsIScrollableFrame : public nsIScrollbarMediator {
|
|
public:
|
|
typedef mozilla::CSSIntPoint CSSIntPoint;
|
|
|
|
NS_DECL_QUERYFRAME_TARGET(nsIScrollableFrame)
|
|
|
|
/**
|
|
* Get the frame for the content that we are scrolling within
|
|
* this scrollable frame.
|
|
*/
|
|
virtual nsIFrame* GetScrolledFrame() const = 0;
|
|
|
|
/**
|
|
* Get the styles (NS_STYLE_OVERFLOW_SCROLL, NS_STYLE_OVERFLOW_HIDDEN,
|
|
* or NS_STYLE_OVERFLOW_AUTO) governing the horizontal and vertical
|
|
* scrollbars for this frame.
|
|
*/
|
|
virtual mozilla::ScrollbarStyles GetScrollbarStyles() const = 0;
|
|
|
|
enum { HORIZONTAL = 0x01, VERTICAL = 0x02 };
|
|
/**
|
|
* Return the scrollbars which are visible. It's OK to call this during reflow
|
|
* of the scrolled contents, in which case it will reflect the current
|
|
* assumptions about scrollbar visibility.
|
|
*/
|
|
virtual uint32_t GetScrollbarVisibility() const = 0;
|
|
/**
|
|
* Returns the directions in which scrolling is perceived to be allowed.
|
|
* A direction is perceived to be allowed if there is a visible scrollbar
|
|
* for that direction or if the scroll range is at least one device pixel.
|
|
*/
|
|
uint32_t GetPerceivedScrollingDirections() const;
|
|
/**
|
|
* Return the actual sizes of all possible scrollbars. Returns 0 for scrollbar
|
|
* positions that don't have a scrollbar or where the scrollbar is not visible.
|
|
* Do not call this while this frame's descendants are being reflowed, it won't be
|
|
* accurate.
|
|
*/
|
|
virtual nsMargin GetActualScrollbarSizes() const = 0;
|
|
/**
|
|
* Return the sizes of all scrollbars assuming that any scrollbars that could
|
|
* be visible due to overflowing content, are. This can be called during reflow
|
|
* of the scrolled contents.
|
|
*/
|
|
virtual nsMargin GetDesiredScrollbarSizes(nsBoxLayoutState* aState) = 0;
|
|
/**
|
|
* Return the sizes of all scrollbars assuming that any scrollbars that could
|
|
* be visible due to overflowing content, are. This can be called during reflow
|
|
* of the scrolled contents.
|
|
*/
|
|
virtual nsMargin GetDesiredScrollbarSizes(nsPresContext* aPresContext,
|
|
nsRenderingContext* aRC) = 0;
|
|
/**
|
|
* Return the width for non-disappearing scrollbars.
|
|
*/
|
|
virtual nscoord GetNondisappearingScrollbarWidth(nsPresContext* aPresContext,
|
|
nsRenderingContext* aRC) = 0;
|
|
/**
|
|
* GetScrolledRect is designed to encapsulate deciding which
|
|
* directions of overflow should be reachable by scrolling and which
|
|
* should not. Callers should NOT depend on it having any particular
|
|
* behavior (although nsXULScrollFrame currently does).
|
|
*
|
|
* This should only be called when the scrolled frame has been
|
|
* reflowed with the scroll port size given in mScrollPort.
|
|
*
|
|
* Currently it allows scrolling down and to the right for
|
|
* nsHTMLScrollFrames with LTR directionality and for all
|
|
* nsXULScrollFrames, and allows scrolling down and to the left for
|
|
* nsHTMLScrollFrames with RTL directionality.
|
|
*/
|
|
virtual nsRect GetScrolledRect() const = 0;
|
|
/**
|
|
* Get the area of the scrollport relative to the origin of this frame's
|
|
* border-box.
|
|
* This is the area of this frame minus border and scrollbars.
|
|
*/
|
|
virtual nsRect GetScrollPortRect() const = 0;
|
|
/**
|
|
* Get the offset of the scrollport origin relative to the scrolled
|
|
* frame origin. Typically the position will be non-negative.
|
|
* This will always be a multiple of device pixels.
|
|
*/
|
|
virtual nsPoint GetScrollPosition() const = 0;
|
|
/**
|
|
* As GetScrollPosition(), but uses the top-right as origin for RTL frames.
|
|
*/
|
|
virtual nsPoint GetLogicalScrollPosition() const = 0;
|
|
/**
|
|
* Get the area that must contain the scroll position. Typically
|
|
* (but not always, e.g. for RTL content) x and y will be 0, and
|
|
* width or height will be nonzero if the content can be scrolled in
|
|
* that direction. Since scroll positions must be a multiple of
|
|
* device pixels, the range extrema will also be a multiple of
|
|
* device pixels.
|
|
*/
|
|
virtual nsRect GetScrollRange() const = 0;
|
|
/**
|
|
* Get the size of the scroll port to use when clamping the scroll
|
|
* position.
|
|
*/
|
|
virtual nsSize GetScrollPositionClampingScrollPortSize() const = 0;
|
|
/**
|
|
* Get the element resolution.
|
|
*/
|
|
virtual gfxSize GetResolution() const = 0;
|
|
/**
|
|
* Set the element resolution.
|
|
*/
|
|
virtual void SetResolution(const gfxSize& aResolution) = 0;
|
|
/**
|
|
* Return how much we would try to scroll by in each direction if
|
|
* asked to scroll by one "line" vertically and horizontally.
|
|
*/
|
|
virtual nsSize GetLineScrollAmount() const = 0;
|
|
/**
|
|
* Return how much we would try to scroll by in each direction if
|
|
* asked to scroll by one "page" vertically and horizontally.
|
|
*/
|
|
virtual nsSize GetPageScrollAmount() const = 0;
|
|
|
|
/**
|
|
* When a scroll operation is requested, we ask for instant, smooth,
|
|
* smooth msd, or normal scrolling.
|
|
*
|
|
* SMOOTH scrolls have a symmetrical acceleration and deceleration curve
|
|
* modeled with a set of splines that guarantee that the destination will be
|
|
* reached over a fixed time interval. SMOOTH will only be smooth if smooth
|
|
* scrolling is actually enabled. This behavior is utilized by keyboard and
|
|
* mouse wheel scrolling events.
|
|
*
|
|
* SMOOTH_MSD implements a physically based model that approximates the
|
|
* behavior of a mass-spring-damper system. SMOOTH_MSD scrolls have a
|
|
* non-symmetrical acceleration and deceleration curve, can potentially
|
|
* overshoot the destination on intermediate frames, and complete over a
|
|
* variable time interval. SMOOTH_MSD will only be smooth if cssom-view
|
|
* smooth-scrolling is enabled.
|
|
*
|
|
* INSTANT is always synchronous, NORMAL can be asynchronous.
|
|
*
|
|
* If an INSTANT scroll request happens while a SMOOTH or async scroll is
|
|
* already in progress, the async scroll is interrupted and we instantly
|
|
* scroll to the destination.
|
|
*
|
|
* If an INSTANT or SMOOTH scroll request happens while a SMOOTH_MSD scroll
|
|
* is already in progress, the SMOOTH_MSD scroll is interrupted without
|
|
* first scrolling to the destination.
|
|
*/
|
|
enum ScrollMode { INSTANT, SMOOTH, SMOOTH_MSD, NORMAL };
|
|
/**
|
|
* @note This method might destroy the frame, pres shell and other objects.
|
|
* Clamps aScrollPosition to GetScrollRange and sets the scroll position
|
|
* to that value.
|
|
* @param aRange If non-null, specifies area which contains aScrollPosition
|
|
* and can be used for choosing a performance-optimized scroll position.
|
|
* Any point within this area can be chosen.
|
|
* The choosen point will be as close as possible to aScrollPosition.
|
|
*/
|
|
virtual void ScrollTo(nsPoint aScrollPosition, ScrollMode aMode,
|
|
const nsRect* aRange = nullptr) = 0;
|
|
/**
|
|
* @note This method might destroy the frame, pres shell and other objects.
|
|
* Scrolls to a particular position in integer CSS pixels.
|
|
* Keeps the exact current horizontal or vertical position if the current
|
|
* position, rounded to CSS pixels, matches aScrollPosition. If
|
|
* aScrollPosition.x/y is different from the current CSS pixel position,
|
|
* makes sure we only move in the direction given by the difference.
|
|
*
|
|
* When aMode is SMOOTH, INSTANT, or NORMAL, GetScrollPositionCSSPixels (the
|
|
* scroll position after rounding to CSS pixels) will be exactly
|
|
* aScrollPosition at the end of the scroll animation.
|
|
*
|
|
* When aMode is SMOOTH_MSD, intermediate animation frames may be outside the
|
|
* range and / or moving in any direction; GetScrollPositionCSSPixels will be
|
|
* exactly aScrollPosition at the end of the scroll animation unless the
|
|
* SMOOTH_MSD animation is interrupted.
|
|
*/
|
|
virtual void ScrollToCSSPixels(const CSSIntPoint& aScrollPosition,
|
|
nsIScrollableFrame::ScrollMode aMode
|
|
= nsIScrollableFrame::INSTANT) = 0;
|
|
/**
|
|
* @note This method might destroy the frame, pres shell and other objects.
|
|
* Scrolls to a particular position in float CSS pixels.
|
|
* This does not guarantee that GetScrollPositionCSSPixels equals
|
|
* aScrollPosition afterward. It tries to scroll as close to
|
|
* aScrollPosition as possible while scrolling by an integer
|
|
* number of layer pixels (so the operation is fast and looks clean).
|
|
*/
|
|
virtual void ScrollToCSSPixelsApproximate(const mozilla::CSSPoint& aScrollPosition,
|
|
nsIAtom *aOrigin = nullptr) = 0;
|
|
|
|
/**
|
|
* Returns the scroll position in integer CSS pixels, rounded to the nearest
|
|
* pixel.
|
|
*/
|
|
virtual CSSIntPoint GetScrollPositionCSSPixels() = 0;
|
|
/**
|
|
* When scrolling by a relative amount, we can choose various units.
|
|
*/
|
|
enum ScrollUnit { DEVICE_PIXELS, LINES, PAGES, WHOLE };
|
|
/**
|
|
* @note This method might destroy the frame, pres shell and other objects.
|
|
* Modifies the current scroll position by aDelta units given by aUnit,
|
|
* clamping it to GetScrollRange. If WHOLE is specified as the unit,
|
|
* content is scrolled all the way in the direction(s) given by aDelta.
|
|
* @param aOverflow if non-null, returns the amount that scrolling
|
|
* was clamped by in each direction (how far we moved the scroll position
|
|
* to bring it back into the legal range). This is never negative. The
|
|
* values are in device pixels.
|
|
*/
|
|
virtual void ScrollBy(nsIntPoint aDelta, ScrollUnit aUnit, ScrollMode aMode,
|
|
nsIntPoint* aOverflow = nullptr,
|
|
nsIAtom* aOrigin = nullptr,
|
|
bool aIsMomentum = false) = 0;
|
|
/**
|
|
* @note This method might destroy the frame, pres shell and other objects.
|
|
* This tells the scroll frame to try scrolling to the scroll
|
|
* position that was restored from the history. This must be called
|
|
* at least once after state has been restored. It is called by the
|
|
* scrolled frame itself during reflow, but sometimes state can be
|
|
* restored after reflows are done...
|
|
* XXX should we take an aMode parameter here? Currently it's instant.
|
|
*/
|
|
virtual void ScrollToRestoredPosition() = 0;
|
|
|
|
/**
|
|
* Add a scroll position listener. This listener must be removed
|
|
* before it is destroyed.
|
|
*/
|
|
virtual void AddScrollPositionListener(nsIScrollPositionListener* aListener) = 0;
|
|
/**
|
|
* Remove a scroll position listener.
|
|
*/
|
|
virtual void RemoveScrollPositionListener(nsIScrollPositionListener* aListener) = 0;
|
|
|
|
/**
|
|
* Internal method used by scrollbars to notify their scrolling
|
|
* container of changes.
|
|
*/
|
|
virtual void CurPosAttributeChanged(nsIContent* aChild) = 0;
|
|
|
|
/**
|
|
* Allows the docshell to request that the scroll frame post an event
|
|
* after being restored from history.
|
|
*/
|
|
NS_IMETHOD PostScrolledAreaEventForCurrentArea() = 0;
|
|
|
|
/**
|
|
* Returns true if this scrollframe is being "actively scrolled".
|
|
* This basically means that we should allocate resources in the
|
|
* expectation that scrolling is going to happen.
|
|
*/
|
|
virtual bool IsScrollingActive() = 0;
|
|
/**
|
|
* Returns true if the scrollframe is currently processing an async
|
|
* or smooth scroll.
|
|
*/
|
|
virtual bool IsProcessingAsyncScroll() = 0;
|
|
/**
|
|
* Call this when the layer(s) induced by active scrolling are being
|
|
* completely redrawn.
|
|
*/
|
|
virtual void ResetScrollPositionForLayerPixelAlignment() = 0;
|
|
/**
|
|
* Was the current presentation state for this frame restored from history?
|
|
*/
|
|
virtual bool DidHistoryRestore() const = 0;
|
|
/**
|
|
* Was the current resolution set by the user or just default initialized?
|
|
*/
|
|
virtual bool IsResolutionSet() const = 0;
|
|
/**
|
|
* Clear the flag so that DidHistoryRestore() returns false until the next
|
|
* RestoreState call.
|
|
* @see nsIStatefulFrame::RestoreState
|
|
*/
|
|
virtual void ClearDidHistoryRestore() = 0;
|
|
/**
|
|
* Determine if the passed in rect is nearly visible according to the image
|
|
* visibility heuristics for how close it is to the visible scrollport.
|
|
*/
|
|
virtual bool IsRectNearlyVisible(const nsRect& aRect) = 0;
|
|
/**
|
|
* Expand the given rect taking into account which directions we can scroll
|
|
* and how far we want to expand for image visibility purposes.
|
|
*/
|
|
virtual nsRect ExpandRectToNearlyVisible(const nsRect& aRect) const = 0;
|
|
/**
|
|
* Returns the origin passed in to the last ScrollToImpl call that took
|
|
* effect.
|
|
*/
|
|
virtual nsIAtom* OriginOfLastScroll() = 0;
|
|
/**
|
|
* Returns the current generation counter for the scroll. This counter
|
|
* increments every time the scroll position is set.
|
|
*/
|
|
virtual uint32_t CurrentScrollGeneration() = 0;
|
|
/**
|
|
* Clears the "origin of last scroll" property stored in this frame, if
|
|
* the generation counter passed in matches the current scroll generation
|
|
* counter.
|
|
*/
|
|
virtual void ResetOriginIfScrollAtGeneration(uint32_t aGeneration) = 0;
|
|
/**
|
|
* Determine whether it is desirable to be able to asynchronously scroll this
|
|
* scroll frame.
|
|
*/
|
|
virtual bool WantAsyncScroll() const = 0;
|
|
};
|
|
|
|
#endif
|