gecko-dev/layout/tables/nsTableRowGroupFrame.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape 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/NPL/
 *
 * 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.org 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 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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#include "nsCOMPtr.h"
#include "nsTableRowGroupFrame.h"
#include "nsTableRowFrame.h"
#include "nsTableFrame.h"
#include "nsTableCellFrame.h"
#include "nsIRenderingContext.h"
#include "nsIPresContext.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsIContent.h"
#include "nsIView.h"
#include "nsIReflowCommand.h"
#include "nsHTMLIIDs.h"
#include "nsIDeviceContext.h"
#include "nsHTMLAtoms.h"
#include "nsIStyleSet.h"
#include "nsIPresShell.h"
#include "nsLayoutAtoms.h"
#include "nsCSSRendering.h"
#include "nsHTMLParts.h"

#include "nsCellMap.h"//table cell navigation

nsTableRowGroupFrame::nsTableRowGroupFrame()
{
  SetRepeatable(PR_FALSE);
#ifdef DEBUG_TABLE_REFLOW_TIMING
  mTimer = new nsReflowTimer(this);
#endif
}

nsTableRowGroupFrame::~nsTableRowGroupFrame()
{
#ifdef DEBUG_TABLE_REFLOW_TIMING
  nsTableFrame::DebugReflowDone(this);
#endif
}

/* ----------- nsTableRowGroupFrame ---------- */
nsrefcnt nsTableRowGroupFrame::AddRef(void)
{
  return 1;//implementation of nsLineIterator
}

nsrefcnt nsTableRowGroupFrame::Release(void)
{
  return 1;//implementation of nsLineIterator
}


nsresult
nsTableRowGroupFrame::QueryInterface(const nsIID& aIID, void** aInstancePtr)
{
  if (NULL == aInstancePtr) {
    return NS_ERROR_NULL_POINTER;
  }
  static NS_DEFINE_IID(kITableRowGroupIID, NS_ITABLEROWGROUPFRAME_IID);
  if (aIID.Equals(kITableRowGroupIID)) {
    *aInstancePtr = (void*)this;
    return NS_OK;
  }
  else if (aIID.Equals(NS_GET_IID(nsILineIteratorNavigator))) 
  { // note there is no addref here, frames are not addref'd
    *aInstancePtr = (void*)(nsILineIteratorNavigator*)this;
    return NS_OK;
  }
  else {
    return nsHTMLContainerFrame::QueryInterface(aIID, aInstancePtr);
  }
}

PRInt32
nsTableRowGroupFrame::GetRowCount()
{  
  PRInt32 count = 0; // init return

  // loop through children, adding one to aCount for every legit row
  nsIFrame* childFrame = GetFirstFrame();
  while (PR_TRUE) {
    if (!childFrame)
      break;
    const nsStyleDisplay* childDisplay;
    childFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)childDisplay));
    if (NS_STYLE_DISPLAY_TABLE_ROW == childDisplay->mDisplay)
      count++;
    GetNextFrame(childFrame, &childFrame);
  }
  return count;
}

PRInt32 nsTableRowGroupFrame::GetStartRowIndex()
{
  PRInt32 result = -1;
  nsIFrame* childFrame = GetFirstFrame();
  while (PR_TRUE) {
    if (!childFrame)
      break;
    const nsStyleDisplay *childDisplay;
    childFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)childDisplay));
    if (NS_STYLE_DISPLAY_TABLE_ROW == childDisplay->mDisplay) {
      result = ((nsTableRowFrame *)childFrame)->GetRowIndex();
      break;
    }
    GetNextFrame(childFrame, &childFrame);
  }
  // if the row group doesn't have any children, get it the hard way
  if (-1 == result) {
    nsTableFrame* tableFrame;
    nsTableFrame::GetTableFrame(this, tableFrame);
    if (tableFrame) {
      return tableFrame->GetStartRowIndex(*this);
    }
  }
      
  return result;
}

nsresult
nsTableRowGroupFrame::InitRepeatedFrame(nsIPresContext*       aPresContext,
                                        nsTableRowGroupFrame* aHeaderFooterFrame)
{
  nsIFrame* originalRowFrame;
  nsIFrame* copyRowFrame = GetFirstFrame();

  aHeaderFooterFrame->FirstChild(aPresContext, nsnull, &originalRowFrame);
  while (copyRowFrame) {
    // Set the row frame index
    int rowIndex = ((nsTableRowFrame*)originalRowFrame)->GetRowIndex();
    ((nsTableRowFrame*)copyRowFrame)->SetRowIndex(rowIndex);

    // For each table cell frame set its column index
    nsIFrame* originalCellFrame;
    nsIFrame* copyCellFrame;
    originalRowFrame->FirstChild(aPresContext, nsnull, &originalCellFrame);
    copyRowFrame->FirstChild(aPresContext, nsnull, &copyCellFrame);
    while (copyCellFrame) {
      nsIAtom*  frameType;
      copyCellFrame->GetFrameType(&frameType);

      if (nsLayoutAtoms::tableCellFrame == frameType) {
  #ifdef NS_DEBUG
        nsIContent* content1;
        nsIContent* content2;
        originalCellFrame->GetContent(&content1);
        copyCellFrame->GetContent(&content2);
        NS_ASSERTION(content1 == content2, "cell frames have different content");
        NS_IF_RELEASE(content1);
        NS_IF_RELEASE(content2);
  #endif
        PRInt32 colIndex;
        ((nsTableCellFrame*)originalCellFrame)->GetColIndex(colIndex);
        ((nsTableCellFrame*)copyCellFrame)->InitCellFrame(colIndex);
      }
      NS_IF_RELEASE(frameType);

      // Move to the next cell frame
      copyCellFrame->GetNextSibling(&copyCellFrame);
      originalCellFrame->GetNextSibling(&originalCellFrame);
    }

    // Move to the next row frame
    GetNextFrame(originalRowFrame, &originalRowFrame);
    GetNextFrame(copyRowFrame, &copyRowFrame);
  }

  return NS_OK;
}

NS_METHOD nsTableRowGroupFrame::Paint(nsIPresContext*      aPresContext,
                                      nsIRenderingContext& aRenderingContext,
                                      const nsRect&        aDirtyRect,
                                      nsFramePaintLayer    aWhichLayer,
                                      PRUint32             aFlags)
{
  PRBool isVisible;
  if (NS_SUCCEEDED(IsVisibleForPainting(aPresContext, aRenderingContext, PR_FALSE, &isVisible)) && !isVisible) {
    return NS_OK;
  }

  nsCompatibility mode;
  aPresContext->GetCompatibilityMode(&mode);

  if ((NS_FRAME_PAINT_LAYER_BACKGROUND == aWhichLayer) &&  
      (eCompatibility_Standard == mode)) {
    const nsStyleVisibility* vis = 
    (const nsStyleVisibility*)mStyleContext->GetStyleData(eStyleStruct_Visibility);
    if (vis->IsVisibleOrCollapsed()) {
      const nsStyleBorder* border =
        (const nsStyleBorder*)mStyleContext->GetStyleData(eStyleStruct_Border);
      const nsStyleBackground* color =
        (const nsStyleBackground*)mStyleContext->GetStyleData(eStyleStruct_Background);
      nsRect rect(0,0,mRect.width, mRect.height);
      nsCSSRendering::PaintBackground(aPresContext, aRenderingContext, this,
                                      aDirtyRect, rect, *color, *border, 0, 0);
    }
  }

#ifdef DEBUG
  // for debug...
  if ((NS_FRAME_PAINT_LAYER_DEBUG == aWhichLayer) && GetShowFrameBorders()) {
    aRenderingContext.SetColor(NS_RGB(0,255,0));
    aRenderingContext.DrawRect(0, 0, mRect.width, mRect.height);
  }
#endif

  if ((NS_FRAME_PAINT_LAYER_BACKGROUND == aWhichLayer) &&  
      (eCompatibility_Standard == mode)) {
    // paint the backgrouds of the rows, skipping the cells
    nsIFrame* kid = mFrames.FirstChild();
    while (kid) {
      PaintChild(aPresContext, aRenderingContext, aDirtyRect, kid, aWhichLayer, NS_ROW_FRAME_PAINT_SKIP_CELLS);
      kid->GetNextSibling(&kid);
    }
    // paint the backgrounds of the cells and their descendants, skipping the rows
    kid = mFrames.FirstChild();
    while (kid) {
      PaintChild(aPresContext, aRenderingContext, aDirtyRect, kid, aWhichLayer, NS_ROW_FRAME_PAINT_SKIP_ROW);
      kid->GetNextSibling(&kid);
    }
  }
  else {
    PaintChildren(aPresContext, aRenderingContext, aDirtyRect, aWhichLayer);
  }
  return NS_OK;
  /*nsFrame::Paint(aPresContext, aRenderingContext, aDirtyRect, aWhichLayer);*/

}

PRIntn
nsTableRowGroupFrame::GetSkipSides() const
{
  PRIntn skip = 0;
  if (nsnull != mPrevInFlow) {
    skip |= 1 << NS_SIDE_TOP;
  }
  if (nsnull != mNextInFlow) {
    skip |= 1 << NS_SIDE_BOTTOM;
  }
  return skip;
}

// aDirtyRect is in our coordinate system
// child rect's are also in our coordinate system
// overloaded method from nsContainerFrame.  The difference is that 
// we don't want to clip our children, so a cell can do a rowspan

void nsTableRowGroupFrame::PaintChildren(nsIPresContext*      aPresContext,
                                         nsIRenderingContext& aRenderingContext,
                                         const nsRect&        aDirtyRect,
                                         nsFramePaintLayer    aWhichLayer,
                                         PRUint32             aFlags)
{
  nsIFrame* kid = GetFirstFrame();
  while (nsnull != kid) {
    nsIView *pView;
     
    kid->GetView(aPresContext, &pView);
    if (nsnull == pView) {
      PRBool clipState;
      nsRect kidRect;
      kid->GetRect(kidRect);
      nsRect damageArea(aDirtyRect);
      // Translate damage area into kid's coordinate system
      nsRect kidDamageArea(damageArea.x - kidRect.x, damageArea.y - kidRect.y,
                           damageArea.width, damageArea.height);
      aRenderingContext.PushState();
      aRenderingContext.Translate(kidRect.x, kidRect.y);
      kid->Paint(aPresContext, aRenderingContext, kidDamageArea, aWhichLayer);
#ifdef DEBUG
      if ((NS_FRAME_PAINT_LAYER_DEBUG == aWhichLayer) &&
          GetShowFrameBorders()) {
        aRenderingContext.SetColor(NS_RGB(255,0,0));
        aRenderingContext.DrawRect(0, 0, kidRect.width, kidRect.height);
      }
#endif
      aRenderingContext.PopState(clipState);
    }
    GetNextFrame(kid, &kid);
  }
}

NS_IMETHODIMP
nsTableRowGroupFrame::GetFrameForPoint(nsIPresContext* aPresContext,
                                   const nsPoint& aPoint, 
                                   nsFramePaintLayer aWhichLayer,
                                   nsIFrame**     aFrame)
{
  // this should act like a block, so we need to override
  return GetFrameForPointUsing(aPresContext, aPoint, nsnull, aWhichLayer, (aWhichLayer == NS_FRAME_PAINT_LAYER_BACKGROUND), aFrame);
}

// Position and size aKidFrame and update our reflow state. The origin of
// aKidRect is relative to the upper-left origin of our frame
void 
nsTableRowGroupFrame::PlaceChild(nsIPresContext*        aPresContext,
																 nsRowGroupReflowState& aReflowState,
																 nsIFrame*              aKidFrame,
																 nsHTMLReflowMetrics&   aDesiredSize)
{
  // Place and size the child
  FinishReflowChild(aKidFrame, aPresContext, aDesiredSize, 0, aReflowState.y, 0);

  // Adjust the running y-offset
  aReflowState.y += aDesiredSize.height;

  // If our height is constrained then update the available height
  if (NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height) {
    aReflowState.availSize.height -= aDesiredSize.height;
  }
}

// Reflow the frames we've already created. If aDirtyOnly is set then only
// reflow dirty frames. This assumes that all of the dirty frames are contiguous.
NS_METHOD 
nsTableRowGroupFrame::ReflowChildren(nsIPresContext*        aPresContext,
                                     nsHTMLReflowMetrics&   aDesiredSize,
                                     nsRowGroupReflowState& aReflowState,
                                     nsReflowStatus&        aStatus,
                                     nsTableRowFrame*       aStartFrame,
                                     PRBool                 aDirtyOnly,
                                     nsTableRowFrame**      aFirstRowReflowed)
{
  nsTableFrame* tableFrame = nsnull;
  nsresult rv = nsTableFrame::GetTableFrame(this, tableFrame);
  if (NS_FAILED(rv) || !tableFrame) return rv;

  nscoord cellSpacingY = tableFrame->GetCellSpacingY();

  if (aFirstRowReflowed) {
    *aFirstRowReflowed = nsnull;
  }
  nsIFrame* lastReflowedRow = nsnull;
  PRBool    adjustSiblings  = PR_TRUE;
  nsIFrame* kidFrame = (aStartFrame) ? aStartFrame : mFrames.FirstChild();

  for ( ; kidFrame; ) {
    // Get the frame state bits
    nsFrameState  frameState;
    kidFrame->GetFrameState(&frameState);

    // See if we should only reflow the dirty child frames
    PRBool doReflowChild = PR_TRUE;
    if (aDirtyOnly && ((frameState & NS_FRAME_IS_DIRTY) == 0)) {
      doReflowChild = PR_FALSE;
    }

    // Reflow the row frame
    if (doReflowChild) {
      nsSize kidAvailSize(aReflowState.availSize);
      if (0 >= kidAvailSize.height)
        kidAvailSize.height = 1;      // XXX: HaCk - we don't handle negative heights yet
      nsHTMLReflowMetrics desiredSize(nsnull);
      desiredSize.width = desiredSize.height = desiredSize.ascent = desiredSize.descent = 0;
  
      // Reflow the child into the available space, giving it as much height as
      // it wants. We'll deal with splitting later after we've computed the row
      // heights, taking into account cells with row spans...
      kidAvailSize.height = NS_UNCONSTRAINEDSIZE;
      nsReflowReason reason = (frameState & NS_FRAME_FIRST_REFLOW) 
                              ? eReflowReason_Initial : aReflowState.reason;
      nsHTMLReflowState kidReflowState(aPresContext, aReflowState.reflowState, kidFrame,
                                       kidAvailSize, reason);
     
      // If this isn't the first row frame, then we can't be at the top of
      // the page anymore...
      if (kidFrame != GetFirstFrame()) {
        kidReflowState.isTopOfPage = PR_FALSE;
      }

      rv = ReflowChild(kidFrame, aPresContext, desiredSize, kidReflowState,
                       0, aReflowState.y, 0, aStatus);

      // Place the child
      nsRect kidRect (0, aReflowState.y, desiredSize.width, desiredSize.height);
      PlaceChild(aPresContext, aReflowState, kidFrame, desiredSize);
      aReflowState.y += cellSpacingY;
      lastReflowedRow = kidFrame;

      if (aFirstRowReflowed && !*aFirstRowReflowed) { 
        nsCOMPtr<nsIAtom> fType;
        kidFrame->GetFrameType(getter_AddRefs(fType));
        if (nsLayoutAtoms::tableRowFrame == fType.get()) {
          *aFirstRowReflowed = (nsTableRowFrame*)kidFrame;
        }
      }
    } else {
      // were done reflowing, so see if we need to reposition the rows that follow
      if (lastReflowedRow) { 
        if (tableFrame->NeedsReflow(aReflowState.reflowState)) {
          adjustSiblings = PR_FALSE;
          break; // don't bother if the table will reflow everything.
        }
      }
      // Adjust the running y-offset so we know where the next row should be placed
      nsSize kidSize;
      kidFrame->GetSize(kidSize);
      aReflowState.y += kidSize.height + cellSpacingY;
    }

    kidFrame->GetNextSibling(&kidFrame); // Get the next child
  }

  // adjust the rows after the ones that were reflowed
  if (lastReflowedRow && adjustSiblings) {
    nsIFrame* nextRow = nsnull;
    lastReflowedRow->GetNextSibling(&nextRow);
    if (nextRow) {
      nsRect lastReflowedRect, nextRect;
      lastReflowedRow->GetRect(lastReflowedRect);
      nextRow->GetRect(nextRect);
      nscoord deltaY = cellSpacingY + lastReflowedRect.YMost() - nextRect.y;
      if (deltaY != 0) {
        AdjustSiblingsAfterReflow(aPresContext, aReflowState, lastReflowedRow, deltaY);
      }
    }
  }

  return rv;
}

void 
nsTableRowGroupFrame::GetNextRowSibling(nsIFrame** aRowFrame)
{
  if (!*aRowFrame) return;
  GetNextFrame(*aRowFrame, aRowFrame);
  while(*aRowFrame) {
    const nsStyleDisplay *display;
    (*aRowFrame)->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)display));
    if (NS_STYLE_DISPLAY_TABLE_ROW == display->mDisplay) {
      return;
    }
    GetNextFrame(*aRowFrame, aRowFrame);
  }
}

// allocate the height of rows which have no cells originating in them
// except with cells with rowspan > 1. Store the height as negative
// to distinguish them from regular rows.
void 
AllocateSpecialHeight(nsIPresContext* aPresContext,
                      nsTableFrame*   aTableFrame,
                      nsIFrame*       aRowFrame,
                      nscoord&        aHeight)
{
  nsIFrame* cellFrame;
  aRowFrame->FirstChild(aPresContext, nsnull, &cellFrame);
  while (cellFrame) {
    nsCOMPtr<nsIAtom> cellType;
    cellFrame->GetFrameType(getter_AddRefs(cellType));
    if (nsLayoutAtoms::tableCellFrame == cellType.get()) {
      PRInt32 rowSpan = aTableFrame->GetEffectiveRowSpan((nsTableCellFrame&)*cellFrame);
      if (rowSpan > 1) {
        // use a simple average to allocate the special row. This is not exact, 
        // but much better than nothing.
        nsSize cellDesSize = ((nsTableCellFrame*)cellFrame)->GetDesiredSize();
        ((nsTableRowFrame*)aRowFrame)->CalculateCellActualSize(cellFrame, cellDesSize.width, 
                                                               cellDesSize.height, cellDesSize.width);
        PRInt32 propHeight = NSToCoordRound((float)cellDesSize.height / (float)rowSpan);
        // special rows store the largest negative value 
        aHeight = PR_MIN(aHeight, -propHeight); 
      }
    }
    cellFrame->GetNextSibling(&cellFrame);
  }
}

/* CalculateRowHeights provides default heights for all rows in the rowgroup.
 * Actual row heights are ultimately determined by the table, when the table
 * height attribute is factored in.
 */
void 
nsTableRowGroupFrame::CalculateRowHeights(nsIPresContext*          aPresContext, 
                                          nsHTMLReflowMetrics&     aDesiredSize,
                                          const nsHTMLReflowState& aReflowState,
                                          nsTableRowFrame*         aStartRowFrameIn)
{
  nsTableFrame* tableFrame = nsnull;
  nsresult rv = nsTableFrame::GetTableFrame(this, tableFrame);
  if (NS_FAILED(rv) || nsnull==tableFrame) return;

  // all table cells have the same top and bottom margins, namely cellSpacingY
  nscoord cellSpacingY = tableFrame->GetCellSpacingY();

  // find the nearest row to the starting row (including the starting row) that isn't spanned into
  nsTableRowFrame* startRowFrame = nsnull;
  nsIFrame* childFrame = GetFirstFrame();
  PRBool foundFirstRow = PR_FALSE;
  while (childFrame) {
    nsCOMPtr<nsIAtom> frameType;
    childFrame->GetFrameType(getter_AddRefs(frameType));
    if (nsLayoutAtoms::tableRowFrame == frameType.get()) {
      PRInt32 rowIndex = ((nsTableRowFrame*)childFrame)->GetRowIndex();
      if (!foundFirstRow || !tableFrame->RowIsSpannedInto(rowIndex)) {
        startRowFrame = (nsTableRowFrame*)childFrame;
        if (!aStartRowFrameIn || (aStartRowFrameIn == startRowFrame)) break;
      }
      else if (aStartRowFrameIn == (nsTableRowFrame*)childFrame) break;
      foundFirstRow = PR_TRUE;
    }
    childFrame->GetNextSibling(&childFrame);
  } 
  if (!startRowFrame) return;

  nsRect startRowRect;
  startRowFrame->GetRect(startRowRect);
  nscoord rowGroupHeight = startRowRect.y;

  PRBool  hasRowSpanningCell = PR_FALSE;
  PRInt32 numRows = GetRowCount() - (startRowFrame->GetRowIndex() - GetStartRowIndex());
  // collect the current height of each row. rows which have 0 height because 
  // they have no cells originating in them without rowspans > 1, are referred to as
  // special rows. The current height of a special row will be a negative number until
  // it comes time to actually resize frames.
  nscoord* rowHeights = nsnull;
  if (numRows > 0) {
    rowHeights = new nscoord[numRows];
    if (!rowHeights) return;
    nsCRT::memset (rowHeights, 0, numRows*sizeof(nscoord));
  } // else - tree row groups need not have rows directly beneath them

  // Step 1:  get the height of the tallest cell in the row and save it for
  //          pass 2. This height is for table cells that originate in this
  //          row and that don't span into the rows that follow
  nsIFrame* rowFrame = startRowFrame;
  PRInt32 rowIndex = 0;

  // For row groups that are split across pages, the first row frame won't
  // necessarily be index 0
  PRInt32 startRowIndex = -1;
  while (rowFrame) {
    nsCOMPtr<nsIAtom> frameType;
    rowFrame->GetFrameType(getter_AddRefs(frameType));
    if (nsLayoutAtoms::tableRowFrame == frameType.get()) {
      if (startRowIndex == -1) {
        startRowIndex = ((nsTableRowFrame*)rowFrame)->GetRowIndex();
      }
      // get the height of the tallest cell in the row (excluding cells that span rows)
      rowHeights[rowIndex] = ((nsTableRowFrame*)rowFrame)->GetTallestCell();

      // See if a cell spans into the row. If so we'll have to do step 2
      if (!hasRowSpanningCell) {
        if (tableFrame->RowIsSpannedInto(rowIndex + startRowIndex)) {
          hasRowSpanningCell = PR_TRUE;
        }
      }
      // special rows need to have some values, so they will get allocations 
      // later. If left at 0, they would get nothing.
      if (0 == rowHeights[rowIndex]) {
        AllocateSpecialHeight(aPresContext, tableFrame, rowFrame, rowHeights[rowIndex]);
      }
      rowIndex++;
    }
    GetNextFrame(rowFrame, &rowFrame); // Get the next row
  }

  // Step 2:  Now account for cells that span rows. A spanning cell's height is the sum of the heights of the 
  //          rows it spans, or it's own desired height, whichever is greater.
  //          If the cell's desired height is the larger value, resize the rows and contained
  //          cells by an equal percentage of the additional space.
  //          We go through this loop twice.  The first time, we are adjusting cell heights
  //          on the fly. The second time through the loop, we're ensuring that subsequent 
  //          row-spanning cells didn't change prior calculations. Since we are guaranteed 
  //          to have found the max height spanners the first time through, we know we only 
  //          need two passes, not an arbitrary number.
  nscoord yOrigin = rowGroupHeight;
  nscoord lastCount = (hasRowSpanningCell) ? 2 : 1;
  for (PRInt32 counter = 0; counter <= lastCount; counter++) {
    rowFrame = startRowFrame;
    rowIndex = 0;
    while (rowFrame) {
      nsCOMPtr<nsIAtom> rowType;
      rowFrame->GetFrameType(getter_AddRefs(rowType));
      if (nsLayoutAtoms::tableRowFrame == rowType.get()) {
        if (hasRowSpanningCell) {
          // check this row for a cell with rowspans
          nsIFrame* cellFrame;
          rowFrame->FirstChild(aPresContext, nsnull, &cellFrame);
          while (cellFrame) {
            nsCOMPtr<nsIAtom> cellType;
            cellFrame->GetFrameType(getter_AddRefs(cellType));
            if (nsLayoutAtoms::tableCellFrame == cellType.get()) {
              PRInt32 rowSpan = tableFrame->GetEffectiveRowSpan(rowIndex + startRowIndex,
                                                                (nsTableCellFrame&)*cellFrame);
              if (rowSpan > 1) { // found a cell with rowspan > 1, determine the height 
                                 // of the rows it spans
                nscoord heightOfRowsSpanned = 0;
                nscoord cellSpacingOfRowsSpanned = 0;
                PRInt32 spanX;
                PRBool cellsOrigInSpan = PR_FALSE; // do any cells originate in the spanned rows
                for (spanX = 0; spanX < rowSpan; spanX++) {
                  PRInt32 rIndex = rowIndex + spanX;
                  if (rowHeights[rIndex] > 0) {
                    // don't consider negative values of special rows
                    heightOfRowsSpanned += rowHeights[rowIndex + spanX];
                    cellsOrigInSpan = PR_TRUE;
                  }
                  if (0 != spanX) {
                    cellSpacingOfRowsSpanned += cellSpacingY;
                  }
                }
                nscoord availHeightOfRowsSpanned = heightOfRowsSpanned + cellSpacingOfRowsSpanned;
  
                // see if the cell's height fits within the rows it spans. If this is
                // pass 1 then use the cell's desired height and not the current height
                // of its frame. That way this works for incremental reflow, too
                nsSize  cellFrameSize;
                cellFrame->GetSize(cellFrameSize);
                if (0 == counter) {
                  nsSize cellDesSize = ((nsTableCellFrame*)cellFrame)->GetDesiredSize();
                  ((nsTableRowFrame*)rowFrame)->CalculateCellActualSize(cellFrame, cellDesSize.width, 
                                                                        cellDesSize.height, cellDesSize.width);
                  cellFrameSize.height = cellDesSize.height;
                  // see if the cell has 'vertical-align: baseline'
                  if (((nsTableCellFrame*)cellFrame)->HasVerticalAlignBaseline()) {
                    // to ensure that a spanning cell with a long descender doesn't
                    // collide with the next row, we need to take into account the shift
                    // that will be done to align the cell on the baseline of the row.
                    cellFrameSize.height += ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent() 
                                          - ((nsTableCellFrame*)cellFrame)->GetDesiredAscent();
                  }
                }
  
                if (availHeightOfRowsSpanned >= cellFrameSize.height) {
                  // the cell's height fits with the available space of the rows it
                  // spans. Set the cell frame's height
                  cellFrame->SizeTo(aPresContext, cellFrameSize.width, availHeightOfRowsSpanned);
                  // Realign cell content based on new height
                  ((nsTableCellFrame*)cellFrame)->VerticallyAlignChild(aPresContext, aReflowState, ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent());
                }
                else {
                  // the cell's height is larger than the available space of the rows it
                  // spans so distribute the excess height to the rows affected
                  nscoord excessAvail = cellFrameSize.height - availHeightOfRowsSpanned;
                  nscoord excessBasis = excessAvail;
  
                  nsTableRowFrame* rowFrameToBeResized = (nsTableRowFrame *)rowFrame;
                  // iterate every row starting at last row spanned and up to the row with
                  // the spanning cell. do this bottom up so that special rows can get a full
                  // allocation before other rows.
                  PRInt32 beginRowIndex = rowIndex + rowSpan - 1;
                  for (PRInt32 rowX = beginRowIndex; (rowX >= rowIndex) && (excessAvail > 0); rowX--) {
                    nscoord excessForRow = 0;
                    // special rows gets as much as they can
                    if (rowHeights[rowX] <= 0) {
                      if ((rowX == beginRowIndex) || (!cellsOrigInSpan)) {
                        if (0 == rowHeights[rowX]) {
                          // give it all since no cell originates in the row
                          excessForRow = excessBasis;
                        }
                        else { // don't let the allocation excced what it needs
                          excessForRow = (excessBasis > -rowHeights[rowX]) ? -rowHeights[rowX] : excessBasis;
                        }
                        rowHeights[rowX] = excessForRow;
                        excessBasis -= excessForRow;
                        excessAvail -= excessForRow;
                      }
                    }
                    else if (cellsOrigInSpan) { // normal rows
                      // The amount of additional space each normal row gets is based on the
                      // percentage of space it occupies, i.e. they don't all get the
                      // same amount of available space
                      float percent = ((float)rowHeights[rowX]) / ((float)heightOfRowsSpanned);
                    
                      // give rows their percentage, except for the first row which gets
                      // the remainder
                      excessForRow = (rowX == rowIndex) 
                                     ? excessAvail  
                                     : NSToCoordRound(((float)(excessBasis)) * percent);
                      // update the row height
                      rowHeights[rowX] += excessForRow;
                      excessAvail -= excessForRow;
                    }
                    // Get the next row frame
                    GetNextRowSibling((nsIFrame**)&rowFrameToBeResized);
                  }
                  // if excessAvail is > 0 it is because !cellsOrigInSpan and the 
                  // allocation involving special rows couldn't allocate everything. 
                  // just give the remainder to the last row spanned.
                  if (excessAvail > 0) {
                    if (rowHeights[beginRowIndex] >= 0) {
                      rowHeights[beginRowIndex] += excessAvail;
                    }
                    else {
                      rowHeights[beginRowIndex] = excessAvail;
                    }
                  }
                }
              }
            }
            cellFrame->GetNextSibling(&cellFrame); // Get the next row child (cell frame)
          }
        }
  
        // If this is the last pass then resize the row to its final size and move the
        // row's position if the previous rows have caused a shift
        if (lastCount == counter) {
          nsRect rowBounds;
          rowFrame->GetRect(rowBounds); 

          PRBool movedFrame = (rowBounds.y != yOrigin);  
          nscoord rowHeight = (rowHeights[rowIndex] > 0) ? rowHeights[rowIndex] : 0;
  
          // Resize the row to its final size and position
          rowBounds.y = yOrigin;
          rowBounds.height = rowHeight;
          rowFrame->SetRect(aPresContext, rowBounds);

          if (movedFrame) {
            nsTableFrame::RePositionViews(aPresContext, rowFrame);
          }
          // set the origin of the next row.
          yOrigin += rowHeight + cellSpacingY;
        }
          
        rowIndex++;
      }
      GetNextFrame(rowFrame, &rowFrame); // Get the next rowgroup child (row frame)
    }
  }

  // step 3: notify the rows of their new heights
  rowFrame = startRowFrame;

  rowIndex = 0;
  while (rowFrame) {
    if (NS_UNCONSTRAINEDSIZE != aReflowState.availableWidth) {
      nsCOMPtr<nsIAtom> rowType;
      rowFrame->GetFrameType(getter_AddRefs(rowType));
      if (nsLayoutAtoms::tableRowFrame == rowType.get()) {
        // Notify the row of the new size
        ((nsTableRowFrame *)rowFrame)->DidResize(aPresContext, aReflowState);
      }
    }

    // Update the running row group height. The height includes frames that
    // aren't rows as well
    nsSize rowSize;
    rowFrame->GetSize(rowSize);
    rowGroupHeight += rowSize.height;
    if (0 != rowIndex) {
      rowGroupHeight += cellSpacingY;
    }

    GetNextFrame(rowFrame, &rowFrame); // Get the next row
    rowIndex++;
  }

  aDesiredSize.height = rowGroupHeight; // Adjust our desired size
  delete [] rowHeights; // cleanup
}

// Called by IR_TargetIsChild() to adjust the sibling frames that follow
// after an incremental reflow of aKidFrame.
// This function is not used for paginated mode so we don't need to deal
// with continuing frames, and it's only called if aKidFrame has no
// cells that span into it and no cells that span across it. That way
// we don't have to deal with rowspans
nsresult
nsTableRowGroupFrame::AdjustSiblingsAfterReflow(nsIPresContext*        aPresContext,
                                                nsRowGroupReflowState& aReflowState,
                                                nsIFrame*              aKidFrame,
                                                nscoord                aDeltaY)
{
  NS_PRECONDITION(NS_UNCONSTRAINEDSIZE == aReflowState.reflowState.availableHeight,
                  "we're not in galley mode");
  nsIFrame* lastKidFrame = aKidFrame;

  // Move the frames that follow aKidFrame by aDeltaY 
  nsIFrame* kidFrame;
  for (aKidFrame->GetNextSibling(&kidFrame); kidFrame; kidFrame->GetNextSibling(&kidFrame)) {
    // Move the frame if we need to
    if (aDeltaY != 0) {
      nsPoint origin;
  
      // Adjust the y-origin
      kidFrame->GetOrigin(origin);
      origin.y += aDeltaY;
  
      kidFrame->MoveTo(aPresContext, origin.x, origin.y);
      nsTableFrame::RePositionViews(aPresContext, kidFrame);
    }

    // Remember the last frame
    lastKidFrame = kidFrame;
  }

  // Update our running y-offset to reflect the bottommost child
  nsRect  rect;
  lastKidFrame->GetRect(rect);
  aReflowState.y = rect.YMost();

  return NS_OK;
}

// Create a continuing frame, add it to the child list, and then push it
// and the frames that follow
void 
nsTableRowGroupFrame::CreateContinuingRowFrame(nsIPresContext& aPresContext,
                                               nsIStyleSet&    aStyleSet,
                                               nsIFrame&       aRowFrame,
                                               nsIFrame**      aContRowFrame)
{
  if (!aContRowFrame) {NS_ASSERTION(PR_FALSE, "bad call"); return;}
  // create the continuing frame which will create continuing cell frames
  aStyleSet.CreateContinuingFrame(&aPresContext, &aRowFrame, this, aContRowFrame);
  if (!*aContRowFrame) return;

  // Add the continuing row frame to the child list
  nsIFrame* nextRow;
  GetNextFrame(&aRowFrame, &nextRow);
  (*aContRowFrame)->SetNextSibling(nextRow);
  aRowFrame.SetNextSibling(*aContRowFrame);
          
  // Push the continuing row frame and the frames that follow
  PushChildren(&aPresContext, *aContRowFrame, &aRowFrame);
}

nscoord
nsTableRowGroupFrame::SplitSpanningCells(nsIPresContext&          aPresContext,
                                         const nsHTMLReflowState& aReflowState,
                                         nsIStyleSet&             aStyleSet,                                         
                                         nsTableFrame&            aTableFrame,
                                         nsTableRowFrame&         aRowFrame,
                                         nscoord                  aRowEndY,
                                         nsTableRowFrame*         aContRowFrame)
{
  PRInt32 rowIndex = aRowFrame.GetRowIndex();
  PRInt32 colCount = aTableFrame.GetColCount();
  nsTableCellFrame* prevCellFrame = nsnull;
 
  nscoord tallestCell = 0;

  for (PRInt32 colX = 0; colX < colCount; colX++) {
    nsTableCellFrame* cellFrame = aTableFrame.GetCellInfoAt(rowIndex, colX);
    if (!cellFrame) continue;
    // use the last in flow since a cell with a row span may have already split.
    cellFrame = (nsTableCellFrame*)cellFrame->GetLastInFlow();

    // See if the cell frame is really in this row, or whether it's a cell spanning from a previous row
    PRInt32 realRowIndex;
    cellFrame->GetRowIndex(realRowIndex);
    if (realRowIndex == rowIndex) {
      prevCellFrame = cellFrame;
    } 
    else {
      nsTableRowFrame* parentFrame;
      nsPoint          cellOrigin;
      nsReflowStatus   status;

      // Ask the cell frame's parent to reflow it to the height of all the
      // rows it spans between its origin and aRowEndY
      cellFrame->GetParent((nsIFrame**)&parentFrame);
      if (!parentFrame) {NS_ASSERTION(PR_FALSE, "bad parent"); return 0;}
      parentFrame->GetOrigin(cellOrigin);
      nscoord cellAvailHeight = aRowEndY - cellOrigin.y;
      nscoord cellHeight = parentFrame->ReflowCellFrame(&aPresContext, aReflowState, cellFrame, 
                                                        cellAvailHeight, status);
      if (NS_FRAME_IS_NOT_COMPLETE(status)) {
        // Create a continuing cell frame since the cell's block split
        nsTableCellFrame* contCellFrame = nsnull;
        aStyleSet.CreateContinuingFrame(&aPresContext, cellFrame, &aRowFrame, (nsIFrame**)&contCellFrame);
        // Add the continuing cell frame to the appropriate row's child list
        if (contCellFrame) {
          if (aContRowFrame) {
            aContRowFrame->InsertCellFrame(contCellFrame, colX);
          }
          else {
            aRowFrame.InsertCellFrame(contCellFrame, prevCellFrame);
          }
          prevCellFrame = contCellFrame;
        }
      }
      else if ((cellHeight > cellAvailHeight) && aContRowFrame) {
        // put the cell on the continuing row frame to give it more space      
        parentFrame->RemoveCellFrame(cellFrame);
        aContRowFrame->InsertCellFrame(cellFrame, colX);
        prevCellFrame = cellFrame;
      }
      tallestCell = PR_MAX(tallestCell, cellHeight);
    }
  }
  return tallestCell;
}

nsresult
nsTableRowGroupFrame::SplitRowGroup(nsIPresContext*          aPresContext,
                                    nsHTMLReflowMetrics&     aDesiredSize,
                                    const nsHTMLReflowState& aReflowState,
                                    nsTableFrame*            aTableFrame,
                                    nsReflowStatus&          aStatus)
{
  nsIFrame* prevRowFrame = nsnull;
  aDesiredSize.height = 0;
  nsresult  rv = NS_OK;

  // get the style set
  nsCOMPtr<nsIStyleSet>  styleSet;
  nsCOMPtr<nsIPresShell> presShell;
  aPresContext->GetShell(getter_AddRefs(presShell));
  if (!presShell) {NS_ASSERTION(PR_FALSE, "no pres shell"); return NS_ERROR_NULL_POINTER;}
  presShell->GetStyleSet(getter_AddRefs(styleSet));
  if (!styleSet) {NS_ASSERTION(PR_FALSE, "no style set"); return NS_ERROR_NULL_POINTER;}

  float p2t;
  aPresContext->GetPixelsToTwips(&p2t);

  nscoord availWidth  = nsTableFrame::RoundToPixel(aReflowState.availableWidth, p2t);
  nscoord availHeight = nsTableFrame::RoundToPixel(aReflowState.availableHeight, p2t);
  nscoord lastDesiredHeight = 0;

  // Walk each of the row frames looking for the first row frame that
  // doesn't fit in the available space
  for (nsIFrame* rowFrame = GetFirstFrame(); rowFrame; GetNextFrame(rowFrame, &rowFrame)) {
    PRBool rowIsOnCurrentPage = PR_TRUE;
    PRBool degenerateRow = PR_FALSE;
    nsRect bounds;
    rowFrame->GetRect(bounds);
    if (bounds.YMost() > availHeight) {
      nsRect actualRect;
      nsRect adjRect;
      aPresContext->GetPageDim(&actualRect, &adjRect);
      nsIFrame* contRowFrame = nsnull;
      nscoord pageHeight = actualRect.height;
      // reflow the row in the availabe space and have it split if it is the 1st
      // row or there is at least 20% of the current page available 
      if (!prevRowFrame || (availHeight - aDesiredSize.height > pageHeight / 5)) { 
        // Reflow the row in the available space and have it split
        nsSize              availSize(availWidth, availHeight - bounds.y);
        nsHTMLReflowState   rowReflowState(aPresContext, aReflowState, rowFrame,
                                          availSize, eReflowReason_Resize);
        nsHTMLReflowMetrics desiredSize(nsnull);

        rv = ReflowChild(rowFrame, aPresContext, desiredSize, rowReflowState,
                         0, 0, NS_FRAME_NO_MOVE_FRAME, aStatus);
        rowFrame->SizeTo(aPresContext, desiredSize.width, desiredSize.height);
        rowFrame->DidReflow(aPresContext, NS_FRAME_REFLOW_FINISHED);
        ((nsTableRowFrame *)rowFrame)->DidResize(aPresContext, aReflowState);

        if (NS_FRAME_IS_NOT_COMPLETE(aStatus)) {
          // the row frame is incomplete and all of the cells' block frames have split
          CreateContinuingRowFrame(*aPresContext, *styleSet.get(), *rowFrame, &contRowFrame);
          aDesiredSize.height += aTableFrame->GetCellSpacingY() + desiredSize.height;
        } 
        else if (0 == desiredSize.height) {
          // the row frame is complete because it had no cells originating in it.
          CreateContinuingRowFrame(*aPresContext, *styleSet.get(), *rowFrame, &contRowFrame);
          aStatus = NS_FRAME_NOT_COMPLETE;
          aDesiredSize.height = availHeight;
          degenerateRow = PR_TRUE;
        }
        else {
          // the row frame is complete because it's minimum height was greater than the 
          // the available height we gave it 
          if (aDesiredSize.height > 0) {
            // put the row on the next page since it needs more height than it was given
            rowIsOnCurrentPage = PR_FALSE;
          }
          else {
            nsIFrame* nextRowFrame;

            // Push the row frame that follows
            GetNextFrame(rowFrame, &nextRowFrame);
          
            if (nextRowFrame) {
              PushChildren(aPresContext, nextRowFrame, rowFrame);
            }
            aStatus = nextRowFrame ? NS_FRAME_NOT_COMPLETE : NS_FRAME_COMPLETE;
            aDesiredSize.height = bounds.YMost();
          }
        }
      }
      else rowIsOnCurrentPage = PR_FALSE;

      if (!rowIsOnCurrentPage) {
        // Push this row frame and those that follow to the next-in-flow
        PushChildren(aPresContext, rowFrame, prevRowFrame);
        aStatus = NS_FRAME_NOT_COMPLETE;
      }
      if (prevRowFrame) {
        nscoord tallestCell = 
          SplitSpanningCells(*aPresContext, aReflowState, *styleSet, *aTableFrame, 
                             *(nsTableRowFrame*)rowFrame, aDesiredSize.height, (nsTableRowFrame*)contRowFrame);
        if (degenerateRow) {
          aDesiredSize.height = lastDesiredHeight + aTableFrame->GetCellSpacingY() + tallestCell;
        }
      }
      break;
    }
    else {
      aDesiredSize.height = bounds.YMost();
      lastDesiredHeight   = aDesiredSize.height;
      prevRowFrame = rowFrame;
    }
  }
  return NS_OK;
}

/** Layout the entire row group.
  * This method stacks rows vertically according to HTML 4.0 rules.
  * Rows are responsible for layout of their children.
  */
NS_METHOD
nsTableRowGroupFrame::Reflow(nsIPresContext*          aPresContext,
                             nsHTMLReflowMetrics&     aDesiredSize,
                             const nsHTMLReflowState& aReflowState,
                             nsReflowStatus&          aStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsTableRowGroupFrame", aReflowState.reason);
#if defined DEBUG_TABLE_REFLOW | DEBUG_TABLE_REFLOW_TIMING
  nsTableFrame::DebugReflow(this, (nsHTMLReflowState&)aReflowState);
#endif

  nsresult rv=NS_OK;
  aStatus = NS_FRAME_COMPLETE;

  nsTableFrame* tableFrame = nsnull;
  rv = nsTableFrame::GetTableFrame(this, tableFrame);
  if (!tableFrame) return NS_ERROR_NULL_POINTER;

  nsRowGroupReflowState state(aReflowState, tableFrame);
  PRBool haveDesiredHeight = PR_FALSE;

  if (eReflowReason_Incremental == aReflowState.reason) {
    rv = IncrementalReflow(aPresContext, aDesiredSize, state, aStatus);
  } 
  else { 
    // Check for an overflow list
    MoveOverflowToChildList(aPresContext);
  
    // Reflow the existing frames. 
    rv = ReflowChildren(aPresContext, aDesiredSize, state, aStatus,
                        nsnull, PR_FALSE);
  
    // Return our desired rect
    aDesiredSize.width = aReflowState.availableWidth;
    aDesiredSize.height = state.y;

    // shrink wrap rows to height of tallest cell in that row
    PRBool isTableUnconstrainedReflow = 
      (NS_UNCONSTRAINEDSIZE == aReflowState.parentReflowState->availableWidth);

    PRBool isPaginated;
    aPresContext->IsPaginated(&isPaginated);
    // Avoid calling CalculateRowHeights. We can avoid it if the table is going to be
    // doing a pass 2 reflow. In the case where the table is getting an unconstrained
    // reflow, then we need to do this because the table will skip the pass 2 reflow,
    // but we need to correctly calculate the row group height and we can't if there
    // are row spans unless we do this step
    if ((eReflowReason_Initial != aReflowState.reason) || 
        isTableUnconstrainedReflow                     ||
        isPaginated) {
      CalculateRowHeights(aPresContext, aDesiredSize, aReflowState);
      haveDesiredHeight = PR_TRUE;
    }

    // See if all the frames fit
    if (aDesiredSize.height > aReflowState.availableHeight) {
      // Nope, find a place to split the row group
      SplitRowGroup(aPresContext, aDesiredSize, aReflowState, tableFrame, aStatus);
    }
  }

  // just set our width to what was available. The table will calculate the width and not use our value.
  aDesiredSize.width = aReflowState.availableWidth;
  if (!haveDesiredHeight) {
    // calculate the height based on the rect of the last row
    aDesiredSize.height = GetHeightOfRows(aPresContext);
  }

#if defined DEBUG_TABLE_REFLOW | DEBUG_TABLE_REFLOW_TIMING
  nsTableFrame::DebugReflow(this, (nsHTMLReflowState&)aReflowState, &aDesiredSize, aStatus);
#endif
  return rv;
}


NS_METHOD 
nsTableRowGroupFrame::IncrementalReflow(nsIPresContext*        aPresContext,
                                        nsHTMLReflowMetrics&   aDesiredSize,
                                        nsRowGroupReflowState& aReflowState,
                                        nsReflowStatus&        aStatus)
{
  nsresult  rv = NS_OK;

  // determine if this frame is the target or not
  nsIFrame* target = nsnull;
  rv = aReflowState.reflowState.reflowCommand->GetTarget(target);
  if (NS_SUCCEEDED(rv) && target) {
    if (this == target)
      rv = IR_TargetIsMe(aPresContext, aDesiredSize, aReflowState, aStatus);
    else {
      // Get the next frame in the reflow chain
      nsIFrame* nextFrame;
      aReflowState.reflowState.reflowCommand->GetNext(nextFrame);

      rv = IR_TargetIsChild(aPresContext, aDesiredSize, aReflowState, aStatus, nextFrame);
    }
  }
  return rv;
}

NS_IMETHODIMP
nsTableRowGroupFrame::AppendFrames(nsIPresContext* aPresContext,
                                   nsIPresShell&   aPresShell,
                                   nsIAtom*        aListName,
                                   nsIFrame*       aFrameList)
{
  // collect the new row frames in an array
  nsAutoVoidArray rows;
  for (nsIFrame* rowFrame = aFrameList; rowFrame; rowFrame->GetNextSibling(&rowFrame)) {
    nsCOMPtr<nsIAtom> frameType;
    rowFrame->GetFrameType(getter_AddRefs(frameType));
    if (nsLayoutAtoms::tableRowFrame == frameType.get()) {
      rows.AppendElement(rowFrame);
    }
  }

  PRInt32 rowIndex = GetRowCount();
  // Append the frames to the sibling chain
  mFrames.AppendFrames(nsnull, aFrameList);

  if (rows.Count() > 0) {
    nsTableFrame* tableFrame = nsnull;
    nsTableFrame::GetTableFrame(this, tableFrame);
    if (tableFrame) {
      tableFrame->AppendRows(*aPresContext, *this, rowIndex, rows);
      // Reflow the new frames. They're already marked dirty, so generate a reflow
      // command that tells us to reflow our dirty child frames
      nsTableFrame::AppendDirtyReflowCommand(&aPresShell, this);
      if (tableFrame->RowIsSpannedInto(rowIndex)) {
        tableFrame->SetNeedStrategyInit(PR_TRUE);
      }
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
nsTableRowGroupFrame::InsertFrames(nsIPresContext* aPresContext,
                                   nsIPresShell&   aPresShell,
                                   nsIAtom*        aListName,
                                   nsIFrame*       aPrevFrame,
                                   nsIFrame*       aFrameList)
{
  nsTableFrame* tableFrame = nsnull;
  nsTableFrame::GetTableFrame(this, tableFrame);
  if (!tableFrame) {
    NS_ASSERTION(PR_FALSE, "no table frame");
    return NS_ERROR_NULL_POINTER;
  }
  // collect the new row frames in an array
  nsVoidArray rows;
  PRBool gotFirstRow = PR_FALSE;
  for (nsIFrame* rowFrame = aFrameList; rowFrame; rowFrame->GetNextSibling(&rowFrame)) {
    nsCOMPtr<nsIAtom> frameType;
    rowFrame->GetFrameType(getter_AddRefs(frameType));
    if (nsLayoutAtoms::tableRowFrame == frameType.get()) {
      rows.AppendElement(rowFrame);
      if (!gotFirstRow) {
        ((nsTableRowFrame*)rowFrame)->SetFirstInserted(PR_TRUE);
        gotFirstRow = PR_TRUE;
        tableFrame->SetRowInserted(PR_TRUE);
      }
    }
  }

  // Insert the frames in the sibling chain
  mFrames.InsertFrames(nsnull, aPrevFrame, aFrameList);

  PRInt32 numRows = rows.Count();
  if (numRows > 0) {
    nsTableRowFrame* prevRow = (nsTableRowFrame *)nsTableFrame::GetFrameAtOrBefore(aPresContext, this, aPrevFrame, nsLayoutAtoms::tableRowFrame);
    PRInt32 rowIndex = (prevRow) ? prevRow->GetRowIndex() + 1 : 0;
    tableFrame->InsertRows(*aPresContext, *this, rows, rowIndex, PR_TRUE);

    // Reflow the new frames. They're already marked dirty, so generate a reflow
    // command that tells us to reflow our dirty child frames
    nsTableFrame::AppendDirtyReflowCommand(&aPresShell, this);
    if (tableFrame->RowIsSpannedInto(rowIndex) || 
        tableFrame->RowHasSpanningCells(rowIndex + numRows - 1)) {
      tableFrame->SetNeedStrategyInit(PR_TRUE);
    }
  }
  return NS_OK;
}

NS_IMETHODIMP
nsTableRowGroupFrame::RemoveFrame(nsIPresContext* aPresContext,
                                  nsIPresShell&   aPresShell,
                                  nsIAtom*        aListName,
                                  nsIFrame*       aOldFrame)
{
  nsTableFrame* tableFrame = nsnull;
  nsTableFrame::GetTableFrame(this, tableFrame);
  if (tableFrame) {
    nsCOMPtr<nsIAtom> frameType;
    aOldFrame->GetFrameType(getter_AddRefs(frameType));
    if (nsLayoutAtoms::tableRowFrame == frameType.get()) {
      // remove the rows from the table (and flag a rebalance)
      tableFrame->RemoveRows(*aPresContext, (nsTableRowFrame &)*aOldFrame, 1, PR_TRUE);

      // XXX this could be optimized (see nsTableFrame::RemoveRows)
      tableFrame->SetNeedStrategyInit(PR_TRUE);
      // Because we haven't added any new frames we don't need to do a pass1
      // reflow. Just generate a reflow command so we reflow the table 
      nsTableFrame::AppendDirtyReflowCommand(&aPresShell, this);
    }
  }
  mFrames.DestroyFrame(aPresContext, aOldFrame);

  return NS_OK;
}

NS_METHOD 
nsTableRowGroupFrame::IR_TargetIsMe(nsIPresContext*        aPresContext,
                                    nsHTMLReflowMetrics&   aDesiredSize,
                                    nsRowGroupReflowState& aReflowState,
                                    nsReflowStatus&        aStatus)
{
  nsresult rv = NS_FRAME_COMPLETE;
  nsIReflowCommand::ReflowType type;
  aReflowState.reflowState.reflowCommand->GetType(type);

  switch (type) {
    case nsIReflowCommand::ReflowDirty: {
      nsRowGroupReflowState state(aReflowState);
      state.reason = eReflowReason_Resize;
      // Reflow the dirty child frames. Typically this is newly added frames.
      nsTableRowFrame* firstRowReflowed;
      rv = ReflowChildren(aPresContext, aDesiredSize, state, aStatus,
                          nsnull, PR_TRUE, &firstRowReflowed);
      CalculateRowHeights(aPresContext, aDesiredSize, aReflowState.reflowState, firstRowReflowed);
      break;
    }
    case nsIReflowCommand::StyleChanged :
      rv = IR_StyleChanged(aPresContext, aDesiredSize, aReflowState, aStatus);
      break;
    case nsIReflowCommand::ContentChanged :
      NS_ASSERTION(PR_FALSE, "illegal reflow type: ContentChanged");
      rv = NS_ERROR_ILLEGAL_VALUE;
      break; 
    default:
      NS_NOTYETIMPLEMENTED("unexpected reflow command type");
      rv = NS_ERROR_NOT_IMPLEMENTED;
      break;
  }

  // XXX If we have a next-in-flow, then we're not complete
  if (mNextInFlow) {
    aStatus = NS_FRAME_NOT_COMPLETE;
  }
  return rv;
}

nscoord 
nsTableRowGroupFrame::GetHeightOfRows(nsIPresContext* aPresContext)
{
  nsTableFrame* tableFrame = nsnull;
  nsresult rv = nsTableFrame::GetTableFrame(this, tableFrame);
  if (!tableFrame) return 0;

  nscoord height = 0;

  // enumerate the rows and total their heights
  nsIFrame* rowFrame = nsnull;
  rv = FirstChild(aPresContext, nsnull, &rowFrame);
  PRInt32 numRows = 0;
  while ((NS_SUCCEEDED(rv)) && rowFrame) {
    const nsStyleDisplay* rowDisplay;
    rowFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowDisplay));
    if (NS_STYLE_DISPLAY_TABLE_ROW == rowDisplay->mDisplay) { 
      nsRect rowRect;
      rowFrame->GetRect(rowRect);
      height += rowRect.height;
      numRows++;
    }
    GetNextFrame(rowFrame, &rowFrame);
  }
  if (numRows > 1) {
    height += (numRows - 1) * tableFrame->GetCellSpacingY(); // add in cell spacing
  }

  return height;
}

// Recovers the reflow state to what it should be if aKidFrame is about
// to be reflowed. Restores availSize, y
nsresult
nsTableRowGroupFrame::RecoverState(nsRowGroupReflowState& aReflowState,
                                   nsIFrame*              aKidFrame)
{
  nsTableFrame* tableFrame = nsnull;
  nsTableFrame::GetTableFrame(this, tableFrame);
  nscoord cellSpacingY = tableFrame->GetCellSpacingY();

  // Walk the list of children looking for aKidFrame
  for (nsIFrame* frame = mFrames.FirstChild(); frame; frame->GetNextSibling(&frame)) {
    if (frame == aKidFrame) {
      break;
    }

    // Update the running y-offset
    nsSize  kidSize;
    frame->GetSize(kidSize);
    aReflowState.y += cellSpacingY + kidSize.height;

    // If our height is constrained then update the available height
    if (NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height) {
      aReflowState.availSize.height -= kidSize.height;
    }
  }

  return NS_OK;
}

PRBool
nsTableRowGroupFrame::IsSimpleRowFrame(nsTableFrame* aTableFrame,
                                       nsIFrame*     aFrame)
{
  // Make sure it's a row frame and not a row group frame
  nsCOMPtr<nsIAtom>  frameType;

  aFrame->GetFrameType(getter_AddRefs(frameType));
  if (frameType.get() == nsLayoutAtoms::tableRowFrame) {
    PRInt32 rowIndex = ((nsTableRowFrame*)aFrame)->GetRowIndex();
    
    // It's a simple row frame if there are no cells that span into or
    // across the row
    if (!aTableFrame->RowIsSpannedInto(rowIndex) &&
        !aTableFrame->RowHasSpanningCells(rowIndex)) {
      return PR_TRUE;
    }
  }

  return PR_FALSE;
}

nscoord
GetFrameYMost(nsIFrame* aFrame)
{
  nsRect rect;
  aFrame->GetRect(rect);
  return rect.YMost();
}

nsIFrame*
GetLastRowSibling(nsIFrame* aRowFrame)
{
  nsIFrame* lastRowFrame = nsnull;
  nsIFrame* lastFrame    = aRowFrame;
  while (lastFrame) {
    nsCOMPtr<nsIAtom> fType;
    lastFrame->GetFrameType(getter_AddRefs(fType));
    if (nsLayoutAtoms::tableRowFrame == fType.get()) {
      lastRowFrame = lastFrame;
    }
    lastFrame->GetNextSibling(&lastFrame);
  }
  return lastRowFrame;
}

NS_METHOD 
nsTableRowGroupFrame::IR_TargetIsChild(nsIPresContext*        aPresContext,
                                       nsHTMLReflowMetrics&   aDesiredSize,
                                       nsRowGroupReflowState& aReflowState,
                                       nsReflowStatus&        aStatus,
                                       nsIFrame*              aNextFrame)

{
  nsresult rv;
  
  // Recover the state as if aNextFrame is about to be reflowed
  RecoverState(aReflowState, aNextFrame);

  // Remember the old rect
  nsRect  oldKidRect;
  aNextFrame->GetRect(oldKidRect);

  // Reflow the child giving it as much room as it wants. We'll deal with
  // splitting later after final determination of rows heights taking into
  // account cells with row spans...
  nsSize              kidAvailSize(aReflowState.availSize.width, NS_UNCONSTRAINEDSIZE);
  nsHTMLReflowState   kidReflowState(aPresContext, aReflowState.reflowState,
                                     aNextFrame, kidAvailSize);
  nsSize              kidMaxElementSize;
  nsHTMLReflowMetrics desiredSize(aDesiredSize.maxElementSize ? &kidMaxElementSize : nsnull,
                                  aDesiredSize.mFlags);

  // Pass along the reflow command
  rv = ReflowChild(aNextFrame, aPresContext, desiredSize, kidReflowState,
                   0, aReflowState.y, 0, aStatus);

  // Place the row frame
  nsRect  kidRect(0, aReflowState.y, desiredSize.width, desiredSize.height);
  PlaceChild(aPresContext, aReflowState, aNextFrame, desiredSize);

  // See if the table needs a reflow (e.g., if the column widths have
  // changed). If so, just return and don't bother adjusting the rows
  // that follow
  if (!aReflowState.tableFrame->NeedsReflow(aReflowState.reflowState)) {
    // Only call CalculateRowHeights() if necessary since it can be expensive
    PRBool needToCalcRowHeights = PR_FALSE; 
    if (IsSimpleRowFrame(aReflowState.tableFrame, aNextFrame)) {
      // See if the row changed height
      if (oldKidRect.height == desiredSize.height) {
        // We don't need to do any painting. The row frame has made sure that
        // the cell is properly positioned, and done any necessary repainting.
        // Just calculate our desired height
        aDesiredSize.height = GetFrameYMost(GetLastRowSibling(mFrames.FirstChild()));
      } else {
        // Inform the row of its new height.
        ((nsTableRowFrame*)aNextFrame)->DidResize(aPresContext, aReflowState.reflowState);
        if (aReflowState.tableFrame->IsAutoHeight()) {
          // Because other cells in the row may need to be be aligned differently,
          // repaint the entire row
          // XXX Improve this so the row knows it should bitblt (or repaint) those
          // cells that change position...
          Invalidate(aPresContext, kidRect);

          // Invalidate the area we're offseting. Note that we only repaint within
          // our existing frame bounds.
          // XXX It would be better to bitblt the row frames and not repaint,
          // but we don't have such a view manager function yet...
          if (kidRect.YMost() < mRect.height) {
            nsRect  dirtyRect(0, kidRect.YMost(),
                              mRect.width, mRect.height - kidRect.YMost());
            Invalidate(aPresContext, dirtyRect);
          }

          // Adjust the frames that follow
          AdjustSiblingsAfterReflow(aPresContext, aReflowState, aNextFrame,
                                    desiredSize.height - oldKidRect.height);
          aDesiredSize.height = aReflowState.y;
        }
        else needToCalcRowHeights = PR_TRUE;
      }
    } else {
      if (desiredSize.mNothingChanged) { // mNothingChanges currently only works when a cell is the target
        // the cell frame did not change size. Just calculate our desired height
        aDesiredSize.height = GetFrameYMost(GetLastRowSibling(mFrames.FirstChild()));
      } 
      else needToCalcRowHeights = PR_TRUE;
    }
    if (needToCalcRowHeights) {
      // Adjust the frames that follow... 
      // XXX is this needed since CalculateRowHeights will be called?
      //AdjustSiblingsAfterReflow(aPresContext, aReflowState, aNextFrame,
      //                          desiredSize.height - oldKidRect.height);
    
      // Now recalculate the row heights
      CalculateRowHeights(aPresContext, aDesiredSize, aReflowState.reflowState);
      
      // Because we don't know what changed repaint everything.
      // XXX We should change CalculateRowHeights() to return the bounding
      // rect of what changed. Or whether anything moved or changed size...
      nsRect  dirtyRect(0, 0, mRect.width, mRect.height);
      Invalidate(aPresContext, dirtyRect);
    }
  }
  
  // Return our desired width
  //aDesiredSize.width = aReflowState.reflowState.availableWidth;

  if (mNextInFlow) {
    aStatus = NS_FRAME_NOT_COMPLETE;
  }

  return rv;
}

NS_METHOD 
nsTableRowGroupFrame::IR_StyleChanged(nsIPresContext*        aPresContext,
                                      nsHTMLReflowMetrics&   aDesiredSize,
                                      nsRowGroupReflowState& aReflowState,
                                      nsReflowStatus&        aStatus)
{
  nsresult rv = NS_OK;
  // we presume that all the easy optimizations were done in the nsHTMLStyleSheet before we were called here
  // XXX: we can optimize this when we know which style attribute changed
  aReflowState.tableFrame->SetNeedStrategyInit(PR_TRUE);
  return rv;
}

NS_IMETHODIMP
nsTableRowGroupFrame::GetFrameType(nsIAtom** aType) const
{
  NS_PRECONDITION(nsnull != aType, "null OUT parameter pointer");
  *aType = nsLayoutAtoms::tableRowGroupFrame; 
  NS_ADDREF(*aType);
  return NS_OK;
}


/* ----- global methods ----- */

nsresult 
NS_NewTableRowGroupFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame)
{
  NS_PRECONDITION(aNewFrame, "null OUT ptr");
  if (nsnull == aNewFrame) {
    return NS_ERROR_NULL_POINTER;
  }
  nsTableRowGroupFrame* it = new (aPresShell) nsTableRowGroupFrame;
  if (nsnull == it) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  *aNewFrame = it;
  return NS_OK;
}

NS_IMETHODIMP
nsTableRowGroupFrame::Init(nsIPresContext*  aPresContext,
                           nsIContent*      aContent,
                           nsIFrame*        aParent,
                           nsIStyleContext* aContext,
                           nsIFrame*        aPrevInFlow)
{
  nsresult  rv;

  // Let the base class do its processing
  rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, aContext,
                                  aPrevInFlow);

  // record that children that are ignorable whitespace should be excluded 
  mState |= NS_FRAME_EXCLUDE_IGNORABLE_WHITESPACE;

  return rv;
}

#ifdef DEBUG
NS_IMETHODIMP
nsTableRowGroupFrame::GetFrameName(nsString& aResult) const
{
  return MakeFrameName("TableRowGroup", aResult);
}

NS_IMETHODIMP
nsTableRowGroupFrame::SizeOf(nsISizeOfHandler* aHandler, PRUint32* aResult) const
{
  if (!aResult) {
    return NS_ERROR_NULL_POINTER;
  }
  PRUint32 sum = sizeof(*this);
  *aResult = sum;
  return NS_OK;
}
#endif

//nsILineIterator methods for nsTableFrame
NS_IMETHODIMP
nsTableRowGroupFrame::GetNumLines(PRInt32* aResult)
{
  NS_ENSURE_ARG_POINTER(aResult);
  *aResult = GetRowCount();
  return *aResult; // XXX should return NS_OK
}

NS_IMETHODIMP
nsTableRowGroupFrame::GetDirection(PRBool* aIsRightToLeft)
{
  NS_ENSURE_ARG_POINTER(aIsRightToLeft);
  *aIsRightToLeft = PR_FALSE;
  return NS_OK;
}
  
NS_IMETHODIMP
nsTableRowGroupFrame::GetLine(PRInt32    aLineNumber, 
                              nsIFrame** aFirstFrameOnLine, 
                              PRInt32*   aNumFramesOnLine,
                              nsRect&    aLineBounds, 
                              PRUint32*  aLineFlags)
{
  NS_ENSURE_ARG_POINTER(aFirstFrameOnLine);
  NS_ENSURE_ARG_POINTER(aNumFramesOnLine);
  NS_ENSURE_ARG_POINTER(aLineFlags);

  nsTableFrame* parentFrame = nsnull; 
  if (NS_FAILED(nsTableFrame::GetTableFrame(this, parentFrame)))
    return NS_ERROR_FAILURE;

  nsTableCellMap* cellMap = parentFrame->GetCellMap();
  if(!cellMap)
     return NS_ERROR_FAILURE;

  if(aLineNumber >= cellMap->GetRowCount())
    return NS_ERROR_INVALID_ARG;
  
  *aLineFlags = 0;/// should we fill these in later?
  // not gonna touch aLineBounds right now

  CellData* firstCellData = cellMap->GetCellAt(aLineNumber, 0);
  if(!firstCellData) 
    return NS_ERROR_FAILURE;

  *aFirstFrameOnLine = (nsIFrame*)firstCellData->GetCellFrame();
  if(!(*aFirstFrameOnLine))
  {
    while((aLineNumber > 0)&&(!(*aFirstFrameOnLine)))
    {
      aLineNumber--;
      firstCellData = cellMap->GetCellAt(aLineNumber, 0);
      *aFirstFrameOnLine = (nsIFrame*)firstCellData->GetCellFrame();
    }
  }
  *aNumFramesOnLine = cellMap->GetNumCellsOriginatingInRow(aLineNumber);
  return NS_OK;
}
  
NS_IMETHODIMP
nsTableRowGroupFrame::FindLineContaining(nsIFrame* aFrame, 
                                         PRInt32*  aLineNumberResult)
{
  NS_ENSURE_ARG_POINTER(aFrame);
  NS_ENSURE_ARG_POINTER(aLineNumberResult);

  // make sure it is a rowFrame in the RowGroup
  // - it should be, but we do not validate in every case (see bug 88849)
  nsCOMPtr<nsIAtom> frameType;
  aFrame->GetFrameType(getter_AddRefs(frameType));
  if (frameType.get() != nsLayoutAtoms::tableRowFrame) {
    NS_WARNING("RowGroup contains a frame that is not a row");
    *aLineNumberResult = 0;
    return NS_ERROR_FAILURE;
  } 

  nsTableRowFrame* rowFrame = (nsTableRowFrame*)aFrame;
  *aLineNumberResult = rowFrame->GetRowIndex();

  return NS_OK;
}

NS_IMETHODIMP
nsTableRowGroupFrame::FindLineAt(nscoord  aY, 
                                 PRInt32* aLineNumberResult)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}
#ifdef IBMBIDI
NS_IMETHODIMP
nsTableRowGroupFrame::CheckLineOrder(PRInt32                  aLine,
                                     PRBool                   *aIsReordered,
                                     nsIFrame                 **aFirstVisual,
                                     nsIFrame                 **aLastVisual)
{
  *aIsReordered = PR_FALSE;
  return NS_OK;
}
#endif // IBMBIDI
  
NS_IMETHODIMP
nsTableRowGroupFrame::FindFrameAt(PRInt32    aLineNumber, 
                                  nscoord    aX, 
#ifdef IBMBIDI
                                  PRBool     aCouldBeReordered,
#endif // IBMBIDI
                                  nsIFrame** aFrameFound,
                                  PRBool*    aXIsBeforeFirstFrame, 
                                  PRBool*    aXIsAfterLastFrame)
{
  PRInt32 cellCount = 0;
  CellData* cellData;
  nsIFrame* tempFrame;
  nsRect tempRect;
  nsRect& tempRectRef = tempRect;
  nsresult rv;

  nsTableFrame* parentFrame = nsnull;
  rv = nsTableFrame::GetTableFrame(this, parentFrame);
  nsTableCellMap* cellMap = parentFrame->GetCellMap();
  if(!cellMap)
     return NS_ERROR_FAILURE;

  cellCount = cellMap->GetNumCellsOriginatingInRow(aLineNumber);

  *aXIsBeforeFirstFrame = PR_FALSE;
  *aXIsAfterLastFrame = PR_FALSE;

  PRBool gotParentRect = PR_FALSE;
  for(int i =0;i < cellCount; i++)
  {
    cellData = cellMap->GetCellAt(aLineNumber, i);
    tempFrame = (nsIFrame*)cellData->GetCellFrame();

    if(!tempFrame)
      continue;
    
    tempFrame->GetRect(tempRectRef);//offsetting x to be in row coordinates
    if(!gotParentRect)
    {//only do this once
      nsRect parentRect;
      nsRect& parentRectRef = parentRect;
      nsIFrame* tempParentFrame;

      rv = tempFrame->GetParent(&tempParentFrame);
    
      if(NS_FAILED(rv))
        return rv;
      if(!tempParentFrame)
        return NS_ERROR_FAILURE;

      tempParentFrame->GetRect(parentRectRef);
      aX -= parentRect.x;
      gotParentRect = PR_TRUE;
    }

    if(i==0 &&(aX <= 0))//short circuit for negative x coords
    {
      *aXIsBeforeFirstFrame = PR_TRUE;
      *aFrameFound = tempFrame;
      return NS_OK;
    }
    if(aX < tempRect.x)
    {
      return NS_ERROR_FAILURE;
    }
    if(aX < (tempRect.x + tempRect.width))
    {
      *aFrameFound = tempFrame;
      return NS_OK;
    }
  }
  //x coord not found in frame, return last frame
  *aXIsAfterLastFrame = PR_TRUE;
  *aFrameFound = tempFrame;
  if(!(*aFrameFound))
    return NS_ERROR_FAILURE;
  return NS_OK;
}

NS_IMETHODIMP
nsTableRowGroupFrame::GetNextSiblingOnLine(nsIFrame*& aFrame, 
                                           PRInt32    aLineNumber)
{
  NS_ENSURE_ARG_POINTER(aFrame);

  nsITableCellLayout* cellFrame;
  nsresult result = aFrame->QueryInterface(NS_GET_IID(nsITableCellLayout),(void**)&cellFrame);
  
  if(NS_FAILED(result) || !cellFrame)
    return result?result:NS_ERROR_FAILURE;
  
  nsTableFrame* parentFrame = nsnull;
  result = nsTableFrame::GetTableFrame(this, parentFrame);
  nsTableCellMap* cellMap = parentFrame->GetCellMap();
  if(!cellMap)
     return NS_ERROR_FAILURE;


  PRInt32 colIndex;
  PRInt32& colIndexRef = colIndex;
  cellFrame->GetColIndex(colIndexRef);

  CellData* cellData = cellMap->GetCellAt(aLineNumber, colIndex + 1);
  
  if(!cellData)// if this isnt a valid cell, drop down and check the next line
  {
    cellData = cellMap->GetCellAt(aLineNumber + 1, 0);
    if(!cellData)
    {
      //*aFrame = nsnull;
      return NS_ERROR_FAILURE;
    }
  }

  aFrame = (nsIFrame*)cellData->GetCellFrame();
  if(!aFrame)
  {
    //PRInt32 numCellsInRow = cellMap->GetNumCellsOriginatingInRow(aLineNumber) - 1;
    PRInt32 tempCol = colIndex + 1;
    PRInt32 tempRow = aLineNumber;
    while((tempCol > 0) && (!aFrame))
    {
      tempCol--;
      cellData = cellMap->GetCellAt(aLineNumber, tempCol);
      aFrame = (nsIFrame*)cellData->GetCellFrame();
      if(!aFrame && (tempCol==0))
      {
        while((tempRow > 0) && (!aFrame))
        {
          tempRow--;
          cellData = cellMap->GetCellAt(tempRow, 0);
          aFrame = (nsIFrame*)cellData->GetCellFrame();
        }
      }
    }
  }
  return NS_OK;
}

//end nsLineIterator methods