/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
// vim:cindent:ts=2:et:sw=2:
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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* decision by deleting the provisions above and replace them with the notice
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* the provisions above, a recipient may use your version of this file under
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*
* ***** END LICENSE BLOCK ***** */
/*
* rendering object for CSS display:block and display:list-item objects,
* also used inside table cells
*/
#ifndef nsBlockFrame_h___
#define nsBlockFrame_h___
#include "nsHTMLContainerFrame.h"
#include "nsHTMLParts.h"
#include "nsAbsoluteContainingBlock.h"
#include "nsLineBox.h"
#include "nsCSSPseudoElements.h"
#include "nsStyleSet.h"
enum LineReflowStatus {
// The line was completely reflowed and fit in available width, and we should
// try to pull up content from the next line if possible.
LINE_REFLOW_OK,
// The line was completely reflowed and fit in available width, but we should
// not try to pull up content from the next line.
LINE_REFLOW_STOP,
// We need to reflow the line again at its current vertical position. The
// new reflow should not try to pull up any frames from the next line.
LINE_REFLOW_REDO_NO_PULL,
// We need to reflow the line again at a lower vertical postion where there
// may be more horizontal space due to different float configuration.
LINE_REFLOW_REDO_NEXT_BAND,
// The line did not fit in the available vertical space. Try pushing it to
// the next page or column if it's not the first line on the current page/column.
LINE_REFLOW_TRUNCATED
};
class nsBlockReflowState;
class nsBlockInFlowLineIterator;
class nsBulletFrame;
class nsLineBox;
class nsFirstLineFrame;
class nsILineIterator;
class nsIntervalSet;
/**
* Child list name indices
* @see #GetAdditionalChildListName()
*/
#define NS_BLOCK_LIST_COUNT (NS_CONTAINER_LIST_COUNT_INCL_OC + 4)
/**
* Some invariants:
* -- The overflow out-of-flows list contains the out-of-
* flow frames whose placeholders are in the overflow list.
* -- A given piece of content has at most one placeholder
* frame in a block's normal child list.
* -- A given piece of content can have an unlimited number
* of placeholder frames in the overflow-lines list.
* -- A line containing a continuation placeholder contains
* only continuation placeholders.
* -- While a block is being reflowed, its overflowPlaceholdersList
* frame property points to an nsFrameList in its
* nsBlockReflowState. This list contains placeholders for
* floats whose prev-in-flow is in the block's regular line
* list. The list is always empty/non-existent after the
* block has been reflowed.
* -- In all these frame lists, if there are two frames for
* the same content appearing in the list, then the frames
* appear with the prev-in-flow before the next-in-flow.
* -- While reflowing a block, its overflow line list
* will usually be empty but in some cases will have lines
* (while we reflow the block at its shrink-wrap width).
* In this case any new overflowing content must be
* prepended to the overflow lines.
*/
// see nsHTMLParts.h for the public block state bits
#define NS_BLOCK_NEEDS_BIDI_RESOLUTION 0x00100000
#define NS_BLOCK_HAS_LINE_CURSOR 0x01000000
#define NS_BLOCK_HAS_OVERFLOW_LINES 0x02000000
#define NS_BLOCK_HAS_OVERFLOW_OUT_OF_FLOWS 0x04000000
#define NS_BLOCK_HAS_OVERFLOW_PLACEHOLDERS 0x08000000
// Set on any block that has descendant frames in the normal
// flow with 'clear' set to something other than 'none'
// (including
frames)
#define NS_BLOCK_HAS_CLEAR_CHILDREN 0x10000000
#define nsBlockFrameSuper nsHTMLContainerFrame
#define NS_BLOCK_FRAME_CID \
{ 0xa6cf90df, 0x15b3, 0x11d2,{0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32}}
extern const nsIID kBlockFrameCID;
/*
* Base class for block and inline frames.
* The block frame has an additional named child list:
* - "Absolute-list" which contains the absolutely positioned frames
*
* @see nsGkAtoms::absoluteList
*/
class nsBlockFrame : public nsBlockFrameSuper
{
public:
typedef nsLineList::iterator line_iterator;
typedef nsLineList::const_iterator const_line_iterator;
typedef nsLineList::reverse_iterator reverse_line_iterator;
typedef nsLineList::const_reverse_iterator const_reverse_line_iterator;
line_iterator begin_lines() { return mLines.begin(); }
line_iterator end_lines() { return mLines.end(); }
const_line_iterator begin_lines() const { return mLines.begin(); }
const_line_iterator end_lines() const { return mLines.end(); }
reverse_line_iterator rbegin_lines() { return mLines.rbegin(); }
reverse_line_iterator rend_lines() { return mLines.rend(); }
const_reverse_line_iterator rbegin_lines() const { return mLines.rbegin(); }
const_reverse_line_iterator rend_lines() const { return mLines.rend(); }
friend nsIFrame* NS_NewBlockFrame(nsIPresShell* aPresShell, nsStyleContext* aContext, PRUint32 aFlags);
// nsISupports
NS_IMETHOD QueryInterface(const nsIID& aIID, void** aInstancePtr);
// nsIFrame
NS_IMETHOD Init(nsIContent* aContent,
nsIFrame* aParent,
nsIFrame* aPrevInFlow);
NS_IMETHOD SetInitialChildList(nsIAtom* aListName,
nsIFrame* aChildList);
NS_IMETHOD AppendFrames(nsIAtom* aListName,
nsIFrame* aFrameList);
NS_IMETHOD InsertFrames(nsIAtom* aListName,
nsIFrame* aPrevFrame,
nsIFrame* aFrameList);
NS_IMETHOD RemoveFrame(nsIAtom* aListName,
nsIFrame* aOldFrame);
virtual nsIFrame* GetFirstChild(nsIAtom* aListName) const;
virtual nscoord GetBaseline() const;
virtual nsIAtom* GetAdditionalChildListName(PRInt32 aIndex) const;
virtual void Destroy();
virtual nsSplittableType GetSplittableType() const;
virtual PRBool IsContainingBlock() const;
virtual PRBool IsFloatContainingBlock() const;
NS_IMETHOD BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists);
virtual void InvalidateInternal(const nsRect& aDamageRect,
nscoord aX, nscoord aY, nsIFrame* aForChild,
PRBool aImmediate);
virtual nsIAtom* GetType() const;
virtual PRBool IsFrameOfType(PRUint32 aFlags) const
{
return nsContainerFrame::IsFrameOfType(aFlags &
~(nsIFrame::eCanContainOverflowContainers));
}
#ifdef DEBUG
NS_IMETHOD List(FILE* out, PRInt32 aIndent) const;
NS_IMETHOD_(nsFrameState) GetDebugStateBits() const;
NS_IMETHOD GetFrameName(nsAString& aResult) const;
NS_IMETHOD VerifyTree() const;
#endif
#ifdef ACCESSIBILITY
NS_IMETHOD GetAccessible(nsIAccessible** aAccessible);
#endif
// line cursor methods to speed up searching for the line(s)
// containing a point. The basic idea is that we set the cursor
// property if the lines' combinedArea.ys and combinedArea.yMosts
// are non-decreasing (considering only non-empty combinedAreas;
// empty combinedAreas never participate in event handling or
// painting), and the block has sufficient number of lines. The
// cursor property points to a "recently used" line. If we get a
// series of requests that work on lines
// "near" the cursor, then we can find those nearby lines quickly by
// starting our search at the cursor.
// Clear out line cursor because we're disturbing the lines (i.e., Reflow)
void ClearLineCursor();
// Get the first line that might contain y-coord 'y', or nsnull if you must search
// all lines. If nonnull is returned then we guarantee that the lines'
// combinedArea.ys and combinedArea.yMosts are non-decreasing.
// The actual line returned might not contain 'y', but if not, it is guaranteed
// to be before any line which does contain 'y'.
nsLineBox* GetFirstLineContaining(nscoord y);
// Set the line cursor to our first line. Only call this if you
// guarantee that the lines' combinedArea.ys and combinedArea.yMosts
// are non-decreasing.
void SetupLineCursor();
virtual void ChildIsDirty(nsIFrame* aChild);
virtual PRBool IsVisibleInSelection(nsISelection* aSelection);
virtual PRBool IsEmpty();
virtual PRBool CachedIsEmpty();
virtual PRBool IsSelfEmpty();
virtual void MarkIntrinsicWidthsDirty();
virtual nscoord GetMinWidth(nsIRenderingContext *aRenderingContext);
virtual nscoord GetPrefWidth(nsIRenderingContext *aRenderingContext);
NS_IMETHOD Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus);
NS_IMETHOD AttributeChanged(PRInt32 aNameSpaceID,
nsIAtom* aAttribute,
PRInt32 aModType);
virtual nsresult StealFrame(nsPresContext* aPresContext,
nsIFrame* aChild,
PRBool aForceNormal);
virtual void DeleteNextInFlowChild(nsPresContext* aPresContext,
nsIFrame* aNextInFlow);
/**
* Determines whether the collapsed margin carried out of the last
* line includes the margin-top of a line with clearance (in which
* case we must avoid collapsing that margin with our bottom margin)
*/
PRBool CheckForCollapsedBottomMarginFromClearanceLine();
/** return the topmost block child based on y-index.
* almost always the first or second line, if there is one.
* accounts for lines that hold only compressed white space, etc.
*/
nsIFrame* GetTopBlockChild(nsPresContext *aPresContext);
// Returns the line containing aFrame, or end_lines() if the frame
// isn't in the block.
line_iterator FindLineFor(nsIFrame* aFrame);
static nsresult GetCurrentLine(nsBlockReflowState *aState, nsLineBox **aOutCurrentLine);
// Create a contination for aPlaceholder and its out of flow frame and
// add it to the list of overflow floats
nsresult SplitPlaceholder(nsBlockReflowState& aState, nsIFrame* aPlaceholder);
void UndoSplitPlaceholders(nsBlockReflowState& aState,
nsIFrame* aLastPlaceholder);
PRBool HandleOverflowPlaceholdersForPulledFrame(
nsBlockReflowState& aState, nsIFrame* aFrame);
PRBool HandleOverflowPlaceholdersOnPulledLine(
nsBlockReflowState& aState, nsLineBox* aLine);
static PRBool BlockIsMarginRoot(nsIFrame* aBlock);
static PRBool BlockNeedsSpaceManager(nsIFrame* aBlock);
protected:
nsBlockFrame(nsStyleContext* aContext)
: nsHTMLContainerFrame(aContext)
, mMinWidth(NS_INTRINSIC_WIDTH_UNKNOWN)
, mPrefWidth(NS_INTRINSIC_WIDTH_UNKNOWN)
, mAbsoluteContainer(nsGkAtoms::absoluteList)
{
#ifdef DEBUG
InitDebugFlags();
#endif
}
virtual ~nsBlockFrame();
#ifdef DEBUG
already_AddRefed GetFirstLetterStyle(nsPresContext* aPresContext)
{
return aPresContext->StyleSet()->
ProbePseudoStyleFor(mContent,
nsCSSPseudoElements::firstLetter, mStyleContext);
}
#endif
/*
* Overides member function of nsHTMLContainerFrame. Needed to handle the
* lines in a nsBlockFrame properly.
*/
virtual void PaintTextDecorationLine(nsIRenderingContext& aRenderingContext,
nsPoint aPt,
nsLineBox* aLine,
nscolor aColor,
nscoord aOffset,
nscoord aAscent,
nscoord aSize,
const PRUint8 aDecoration);
void TryAllLines(nsLineList::iterator* aIterator,
nsLineList::iterator* aStartIterator,
nsLineList::iterator* aEndIterator,
PRBool* aInOverflowLines);
void SetFlags(PRUint32 aFlags) {
mState &= ~NS_BLOCK_FLAGS_MASK;
mState |= aFlags;
}
PRBool HaveOutsideBullet() const {
#if defined(DEBUG) && !defined(DEBUG_rods)
if(mState & NS_BLOCK_FRAME_HAS_OUTSIDE_BULLET) {
NS_ASSERTION(mBullet,"NS_BLOCK_FRAME_HAS_OUTSIDE_BULLET flag set and no mBullet");
}
#endif
return 0 != (mState & NS_BLOCK_FRAME_HAS_OUTSIDE_BULLET);
}
/** move the frames contained by aLine by aDY
* if aLine is a block, its child floats are added to the state manager
*/
void SlideLine(nsBlockReflowState& aState,
nsLineBox* aLine, nscoord aDY);
virtual PRIntn GetSkipSides() const;
virtual void ComputeFinalSize(const nsHTMLReflowState& aReflowState,
nsBlockReflowState& aState,
nsHTMLReflowMetrics& aMetrics);
void ComputeCombinedArea(const nsHTMLReflowState& aReflowState,
nsHTMLReflowMetrics& aMetrics);
/** add the frames in aFrameList to this block after aPrevSibling
* this block thinks in terms of lines, but the frame construction code
* knows nothing about lines at all. So we need to find the line that
* contains aPrevSibling and add aFrameList after aPrevSibling on that line.
* new lines are created as necessary to handle block data in aFrameList.
*/
nsresult AddFrames(nsIFrame* aFrameList,
nsIFrame* aPrevSibling);
#ifdef IBMBIDI
/**
* Perform Bidi resolution on this frame
*/
nsresult ResolveBidi();
/**
* Test whether the frame is a form control in a visual Bidi page.
* This is necessary for backwards-compatibility, because most visual
* pages use logical order for form controls so that they will
* display correctly on native widgets in OSs with Bidi support
* @param aPresContext the pres context
* @return whether the frame is a BIDI form control
*/
PRBool IsVisualFormControl(nsPresContext* aPresContext);
#endif
public:
/** does all the real work for removing aDeletedFrame from this
* finds the line containing aFrame.
* handled continued frames
* marks lines dirty as needed
* @param aDestroyFrames if false then we don't actually destroy the
* frame or its next in flows, we just remove them. This does NOT work
* on out of flow frames so always use PR_TRUE for out of flows.
* @param aRemoveOnlyFluidContinuations if true, only in-flows are removed;
* if false, all continuations are removed.
*/
nsresult DoRemoveFrame(nsIFrame* aDeletedFrame, PRBool aDestroyFrames = PR_TRUE,
PRBool aRemoveOnlyFluidContinuations = PR_TRUE);
void ReparentFloats(nsIFrame* aFirstFrame,
nsBlockFrame* aOldParent, PRBool aFromOverflow,
PRBool aReparentSiblings);
protected:
/** grab overflow lines from this block's prevInFlow, and make them
* part of this block's mLines list.
* @return PR_TRUE if any lines were drained.
*/
PRBool DrainOverflowLines(nsBlockReflowState& aState);
/**
* Remove a float from our float list and also the float cache
* for the line its placeholder is on.
*/
line_iterator RemoveFloat(nsIFrame* aFloat);
void CollectFloats(nsIFrame* aFrame, nsFrameList& aList, nsIFrame** aTail,
PRBool aFromOverflow, PRBool aCollectFromSiblings);
// Remove a float, abs, rel positioned frame from the appropriate block's list
static void DoRemoveOutOfFlowFrame(nsIFrame* aFrame);
/** set up the conditions necessary for an resize reflow
* the primary task is to mark the minimumly sufficient lines dirty.
*/
nsresult PrepareResizeReflow(nsBlockReflowState& aState);
/** reflow all lines that have been marked dirty */
nsresult ReflowDirtyLines(nsBlockReflowState& aState);
//----------------------------------------
// Methods for line reflow
/**
* Reflow a line.
* @param aState the current reflow state
* @param aLine the line to reflow. can contain a single block frame
* or contain 1 or more inline frames.
* @param aKeepReflowGoing [OUT] indicates whether the caller should continue to reflow more lines
*/
nsresult ReflowLine(nsBlockReflowState& aState,
line_iterator aLine,
PRBool* aKeepReflowGoing);
// Return PR_TRUE if aLine gets pushed.
PRBool PlaceLine(nsBlockReflowState& aState,
nsLineLayout& aLineLayout,
line_iterator aLine,
PRBool* aKeepReflowGoing);
/**
* Mark |aLine| dirty, and, if necessary because of possible
* pull-up, mark the previous line dirty as well.
*/
nsresult MarkLineDirty(line_iterator aLine);
// XXX where to go
PRBool ShouldJustifyLine(nsBlockReflowState& aState,
line_iterator aLine);
void DeleteLine(nsBlockReflowState& aState,
nsLineList::iterator aLine,
nsLineList::iterator aLineEnd);
//----------------------------------------
// Methods for individual frame reflow
PRBool ShouldApplyTopMargin(nsBlockReflowState& aState,
nsLineBox* aLine);
nsresult ReflowBlockFrame(nsBlockReflowState& aState,
line_iterator aLine,
PRBool* aKeepGoing);
nsresult ReflowInlineFrames(nsBlockReflowState& aState,
line_iterator aLine,
PRBool* aKeepLineGoing);
nsresult DoReflowInlineFrames(nsBlockReflowState& aState,
nsLineLayout& aLineLayout,
line_iterator aLine,
PRBool* aKeepReflowGoing,
LineReflowStatus* aLineReflowStatus,
PRBool aAllowPullUp);
nsresult ReflowInlineFrame(nsBlockReflowState& aState,
nsLineLayout& aLineLayout,
line_iterator aLine,
nsIFrame* aFrame,
LineReflowStatus* aLineReflowStatus);
// An incomplete aReflowStatus indicates the float should be split
// but only if the available height is constrained.
nsresult ReflowFloat(nsBlockReflowState& aState,
nsPlaceholderFrame* aPlaceholder,
nsMargin& aFloatMargin,
nsReflowStatus& aReflowStatus);
//----------------------------------------
// Methods for pushing/pulling lines/frames
virtual nsresult CreateContinuationFor(nsBlockReflowState& aState,
nsLineBox* aLine,
nsIFrame* aFrame,
PRBool& aMadeNewFrame);
// Push aLine which contains a positioned element that was truncated. Clean up any
// placeholders on the same line that were continued. Set aKeepReflowGoing to false.
void PushTruncatedPlaceholderLine(nsBlockReflowState& aState,
line_iterator aLine,
nsIFrame* aLastPlaceholder,
PRBool& aKeepReflowGoing);
nsresult SplitLine(nsBlockReflowState& aState,
nsLineLayout& aLineLayout,
line_iterator aLine,
nsIFrame* aFrame,
LineReflowStatus* aLineReflowStatus);
nsresult PullFrame(nsBlockReflowState& aState,
line_iterator aLine,
nsIFrame*& aFrameResult);
PRBool PullFrameFrom(nsBlockReflowState& aState,
nsLineBox* aLine,
nsBlockFrame* aFromContainer,
PRBool aFromOverflowLine,
nsLineList::iterator aFromLine,
nsIFrame*& aFrameResult);
void PushLines(nsBlockReflowState& aState,
nsLineList::iterator aLineBefore);
void PropagateFloatDamage(nsBlockReflowState& aState,
nsLineBox* aLine,
nscoord aDeltaY);
void CheckFloats(nsBlockReflowState& aState);
//----------------------------------------
// List handling kludge
// If this returns PR_TRUE, the block it's called on should get the
// NS_FRAME_HAS_DIRTY_CHILDREN bit set on it by the caller; either directly
// if it's already in reflow, or via calling FrameNeedsReflow() to schedule a
// reflow.
PRBool RenumberLists(nsPresContext* aPresContext);
PRBool RenumberListsInBlock(nsPresContext* aPresContext,
nsBlockFrame* aContainerFrame,
PRInt32* aOrdinal,
PRInt32 aDepth);
PRBool RenumberListsFor(nsPresContext* aPresContext, nsIFrame* aKid, PRInt32* aOrdinal, PRInt32 aDepth);
static PRBool FrameStartsCounterScope(nsIFrame* aFrame);
void ReflowBullet(nsBlockReflowState& aState,
nsHTMLReflowMetrics& aMetrics);
//----------------------------------------
public:
nsLineList* GetOverflowLines() const;
protected:
nsLineList* RemoveOverflowLines();
nsresult SetOverflowLines(nsLineList* aOverflowLines);
nsFrameList* GetOverflowPlaceholders() const;
/**
* This class is useful for efficiently modifying the out of flow
* overflow list. It gives the client direct writable access to
* the frame list temporarily but ensures that property is only
* written back if absolutely necessary.
*/
struct nsAutoOOFFrameList {
nsFrameList mList;
nsAutoOOFFrameList(nsBlockFrame* aBlock) :
mList(aBlock->GetOverflowOutOfFlows().FirstChild()),
aOldHead(mList.FirstChild()), mBlock(aBlock) {}
~nsAutoOOFFrameList() {
if (mList.FirstChild() != aOldHead) {
mBlock->SetOverflowOutOfFlows(mList);
}
}
protected:
nsIFrame* aOldHead;
nsBlockFrame* mBlock;
};
friend struct nsAutoOOFFrameList;
nsFrameList GetOverflowOutOfFlows() const;
void SetOverflowOutOfFlows(const nsFrameList& aList);
nsIFrame* LastChild();
#ifdef NS_DEBUG
void VerifyLines(PRBool aFinalCheckOK);
void VerifyOverflowSituation();
PRInt32 GetDepth() const;
#endif
nscoord mMinWidth, mPrefWidth;
nsLineList mLines;
// List of all floats in this block
nsFrameList mFloats;
// XXX_fix_me: subclass one more time!
// For list-item frames, this is the bullet frame.
nsBulletFrame* mBullet;
friend class nsBlockReflowState;
friend class nsBlockInFlowLineIterator;
private:
nsAbsoluteContainingBlock mAbsoluteContainer;
#ifdef DEBUG
public:
static PRBool gLamePaintMetrics;
static PRBool gLameReflowMetrics;
static PRBool gNoisy;
static PRBool gNoisyDamageRepair;
static PRBool gNoisyIntrinsic;
static PRBool gNoisyReflow;
static PRBool gReallyNoisyReflow;
static PRBool gNoisySpaceManager;
static PRBool gVerifyLines;
static PRBool gDisableResizeOpt;
static PRInt32 gNoiseIndent;
static const char* kReflowCommandType[];
protected:
static void InitDebugFlags();
#endif
};
#ifdef DEBUG
class AutoNoisyIndenter {
public:
AutoNoisyIndenter(PRBool aDoIndent) : mIndented(aDoIndent) {
if (mIndented) {
nsBlockFrame::gNoiseIndent++;
}
}
~AutoNoisyIndenter() {
if (mIndented) {
nsBlockFrame::gNoiseIndent--;
}
}
private:
PRBool mIndented;
};
#endif
/**
* Iterates over all lines in the prev-in-flows/next-in-flows of this block.
*/
class nsBlockInFlowLineIterator {
public:
typedef nsBlockFrame::line_iterator line_iterator;
nsBlockInFlowLineIterator(nsBlockFrame* aFrame, line_iterator& aLine, PRBool aInOverflow);
line_iterator GetLine() { return mLine; }
nsBlockFrame* GetContainer() { return mFrame; }
PRBool GetInOverflow() { return mInOverflowLines != nsnull; }
/**
* Returns false if there are no more lines. After this has returned false,
* don't call any methods on this object again.
*/
PRBool Next();
/**
* Returns false if there are no more lines. After this has returned false,
* don't call any methods on this object again.
*/
PRBool Prev();
private:
nsBlockFrame* mFrame;
line_iterator mLine;
nsLineList* mInOverflowLines;
};
#endif /* nsBlockFrame_h___ */