Mozilla/mozilla/layout/tables/nsTableRowGroupFrame.cpp
bzbarsky%mit.edu ba5badedcb Change the FrameNeedsReflow API to pass the dirty flags to be added directly to
the method, instead of setting them before calling the method.  That way we can
avoid reflowing the ancestor of a reflow root which is not itself dirty but has
dirty children.  This also makes it harder to set dirty bits inconsistently
with the FrameNeedsReflow call.  Bug 378784, r+sr=dbaron, pending rbs' review
on the mathml parts.


git-svn-id: svn://10.0.0.236/trunk@226007 18797224-902f-48f8-a5cc-f745e15eee43
2007-05-06 19:16:52 +00:00

1904 lines
70 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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.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):
* Mats Palmgren <mats.palmgren@bredband.net>
*
* 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
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsCOMPtr.h"
#include "nsTableRowGroupFrame.h"
#include "nsTableRowFrame.h"
#include "nsTableFrame.h"
#include "nsTableCellFrame.h"
#include "nsIRenderingContext.h"
#include "nsPresContext.h"
#include "nsStyleContext.h"
#include "nsStyleConsts.h"
#include "nsIContent.h"
#include "nsGkAtoms.h"
#include "nsIPresShell.h"
#include "nsCSSRendering.h"
#include "nsHTMLParts.h"
#include "nsCSSFrameConstructor.h"
#include "nsDisplayList.h"
#include "nsCellMap.h"//table cell navigation
nsTableRowGroupFrame::nsTableRowGroupFrame(nsStyleContext* aContext):
nsHTMLContainerFrame(aContext)
{
SetRepeatable(PR_FALSE);
}
nsTableRowGroupFrame::~nsTableRowGroupFrame()
{
}
/* ----------- 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);
}
}
/* virtual */ PRBool
nsTableRowGroupFrame::IsContainingBlock() const
{
return PR_TRUE;
}
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;
if (NS_STYLE_DISPLAY_TABLE_ROW == childFrame->GetStyleDisplay()->mDisplay)
count++;
GetNextFrame(childFrame, &childFrame);
}
return count;
}
PRInt32 nsTableRowGroupFrame::GetStartRowIndex()
{
PRInt32 result = -1;
nsIFrame* childFrame = GetFirstFrame();
while (PR_TRUE) {
if (!childFrame)
break;
if (NS_STYLE_DISPLAY_TABLE_ROW == childFrame->GetStyleDisplay()->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);
if (tableFrame) {
return tableFrame->GetStartRowIndex(*this);
}
}
return result;
}
void nsTableRowGroupFrame::AdjustRowIndices(PRInt32 aRowIndex,
PRInt32 anAdjustment)
{
nsIFrame* rowFrame = GetFirstChild(nsnull);
for ( ; rowFrame; rowFrame = rowFrame->GetNextSibling()) {
if (NS_STYLE_DISPLAY_TABLE_ROW==rowFrame->GetStyleDisplay()->mDisplay) {
PRInt32 index = ((nsTableRowFrame*)rowFrame)->GetRowIndex();
if (index >= aRowIndex)
((nsTableRowFrame *)rowFrame)->SetRowIndex(index+anAdjustment);
}
}
}
nsresult
nsTableRowGroupFrame::InitRepeatedFrame(nsPresContext* aPresContext,
nsTableRowGroupFrame* aHeaderFooterFrame)
{
nsTableRowFrame* copyRowFrame = GetFirstRow();
nsTableRowFrame* originalRowFrame = aHeaderFooterFrame->GetFirstRow();
AddStateBits(NS_REPEATED_ROW_OR_ROWGROUP);
while (copyRowFrame && originalRowFrame) {
copyRowFrame->AddStateBits(NS_REPEATED_ROW_OR_ROWGROUP);
int rowIndex = originalRowFrame->GetRowIndex();
copyRowFrame->SetRowIndex(rowIndex);
// For each table cell frame set its column index
nsTableCellFrame* originalCellFrame = originalRowFrame->GetFirstCell();
nsTableCellFrame* copyCellFrame = copyRowFrame->GetFirstCell();
while (copyCellFrame && originalCellFrame) {
NS_ASSERTION(originalCellFrame->GetContent() == copyCellFrame->GetContent(),
"cell frames have different content");
PRInt32 colIndex;
originalCellFrame->GetColIndex(colIndex);
copyCellFrame->SetColIndex(colIndex);
// Move to the next cell frame
copyCellFrame = copyCellFrame->GetNextCell();
originalCellFrame = originalCellFrame->GetNextCell();
}
// Move to the next row frame
originalRowFrame = originalRowFrame->GetNextRow();
copyRowFrame = copyRowFrame->GetNextRow();
}
return NS_OK;
}
static void
PaintRowGroupBackground(nsIFrame* aFrame, nsIRenderingContext* aCtx,
const nsRect& aDirtyRect, nsPoint aPt)
{
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(aFrame);
nsIRenderingContext::AutoPushTranslation translate(aCtx, aPt.x, aPt.y);
TableBackgroundPainter painter(tableFrame,
TableBackgroundPainter::eOrigin_TableRowGroup,
aFrame->PresContext(), *aCtx,
aDirtyRect - aPt);
painter.PaintRowGroup(NS_STATIC_CAST(nsTableRowGroupFrame*, aFrame));
}
// Handle the child-traversal part of DisplayGenericTablePart
static nsresult
DisplayRows(nsDisplayListBuilder* aBuilder, nsFrame* aFrame,
const nsRect& aDirtyRect, const nsDisplayListSet& aLists)
{
nscoord overflowAbove;
nsTableRowGroupFrame* f = NS_STATIC_CAST(nsTableRowGroupFrame*, aFrame);
// Don't try to use the row cursor if we have to descend into placeholders;
// we might have rows containing placeholders, where the row's overflow
// area doesn't intersect the dirty rect but we need to descend into the row
// to see out of flows
nsIFrame* kid = f->GetStateBits() & NS_FRAME_FORCE_DISPLAY_LIST_DESCEND_INTO
? nsnull : f->GetFirstRowContaining(aDirtyRect.y, &overflowAbove);
if (kid) {
// have a cursor, use it
while (kid) {
if (kid->GetRect().y - overflowAbove >= aDirtyRect.YMost())
break;
nsresult rv = f->BuildDisplayListForChild(aBuilder, kid, aDirtyRect, aLists);
NS_ENSURE_SUCCESS(rv, rv);
kid = kid->GetNextSibling();
}
return NS_OK;
}
// No cursor. Traverse children the hard way and build a cursor while we're at it
nsTableRowGroupFrame::FrameCursorData* cursor = f->SetupRowCursor();
kid = f->GetFirstChild(nsnull);
while (kid) {
nsresult rv = f->BuildDisplayListForChild(aBuilder, kid, aDirtyRect, aLists);
if (NS_FAILED(rv)) {
f->ClearRowCursor();
return rv;
}
if (cursor) {
if (!cursor->AppendFrame(kid)) {
f->ClearRowCursor();
return NS_ERROR_OUT_OF_MEMORY;
}
}
kid = kid->GetNextSibling();
}
if (cursor) {
cursor->FinishBuildingCursor();
}
return NS_OK;
}
NS_IMETHODIMP
nsTableRowGroupFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists)
{
if (!IsVisibleInSelection(aBuilder))
return NS_OK;
PRBool isRoot = aBuilder->IsAtRootOfPseudoStackingContext();
if (isRoot) {
// This background is created regardless of whether this frame is
// visible or not. Visibility decisions are delegated to the
// table background painter.
nsresult rv = aLists.BorderBackground()->AppendNewToTop(new (aBuilder)
nsDisplayGeneric(this, PaintRowGroupBackground, "TableRowGroupBackground"));
NS_ENSURE_SUCCESS(rv, rv);
}
return nsTableFrame::DisplayGenericTablePart(aBuilder, this, aDirtyRect,
aLists, isRoot, DisplayRows);
}
PRIntn
nsTableRowGroupFrame::GetSkipSides() const
{
PRIntn skip = 0;
if (nsnull != GetPrevInFlow()) {
skip |= 1 << NS_SIDE_TOP;
}
if (nsnull != GetNextInFlow()) {
skip |= 1 << NS_SIDE_BOTTOM;
}
return skip;
}
// 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(nsPresContext* aPresContext,
nsRowGroupReflowState& aReflowState,
nsIFrame* aKidFrame,
nsHTMLReflowMetrics& aDesiredSize)
{
// Place and size the child
FinishReflowChild(aKidFrame, aPresContext, nsnull, 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;
}
}
void
nsTableRowGroupFrame::InitChildReflowState(nsPresContext& aPresContext,
PRBool aBorderCollapse,
nsHTMLReflowState& aReflowState)
{
nsMargin collapseBorder;
nsMargin padding(0,0,0,0);
nsMargin* pCollapseBorder = nsnull;
if (aBorderCollapse) {
if (aReflowState.frame) {
if (nsGkAtoms::tableRowFrame == aReflowState.frame->GetType()) {
nsTableRowFrame* rowFrame = (nsTableRowFrame*)aReflowState.frame;
pCollapseBorder = rowFrame->GetBCBorderWidth(collapseBorder);
}
}
}
aReflowState.Init(&aPresContext, -1, -1, pCollapseBorder, &padding);
}
static void
CacheRowHeightsForPrinting(nsPresContext* aPresContext,
nsTableRowFrame* aFirstRow)
{
for (nsTableRowFrame* row = aFirstRow; row; row = row->GetNextRow()) {
if (!row->GetPrevInFlow()) {
row->SetHasUnpaginatedHeight(PR_TRUE);
row->SetUnpaginatedHeight(aPresContext, row->GetSize().height);
}
}
}
NS_METHOD
nsTableRowGroupFrame::ReflowChildren(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
nsRowGroupReflowState& aReflowState,
nsReflowStatus& aStatus,
PRBool* aPageBreakBeforeEnd)
{
if (aPageBreakBeforeEnd)
*aPageBreakBeforeEnd = PR_FALSE;
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (!tableFrame)
ABORT1(NS_ERROR_NULL_POINTER);
nsresult rv = NS_OK;
PRBool borderCollapse = tableFrame->IsBorderCollapse();
nscoord cellSpacingY = tableFrame->GetCellSpacingY();
// XXXldb Should we really be checking this rather than available height?
// (Think about multi-column layout!)
PRBool isPaginated = aPresContext->IsPaginated();
PRBool haveRow = PR_FALSE;
PRBool reflowAllKids = aReflowState.reflowState.ShouldReflowAllKids() ||
tableFrame->IsGeometryDirty();
PRBool needToCalcRowHeights = reflowAllKids;
for (nsIFrame* kidFrame = mFrames.FirstChild(); kidFrame;
kidFrame = kidFrame->GetNextSibling()) {
if (kidFrame->GetType() != nsGkAtoms::tableRowFrame) {
// XXXldb nsCSSFrameConstructor needs to enforce this!
NS_NOTREACHED("yikes, a non-row child");
continue;
}
haveRow = PR_TRUE;
// Reflow the row frame
if (reflowAllKids ||
NS_SUBTREE_DIRTY(kidFrame) ||
(aReflowState.reflowState.mFlags.mSpecialHeightReflow &&
(isPaginated || (kidFrame->GetStateBits() &
NS_FRAME_CONTAINS_RELATIVE_HEIGHT)))) {
nsSize oldKidSize = kidFrame->GetSize();
// XXXldb We used to only pass aDesiredSize.mFlags through for the
// incremental reflow codepath.
nsHTMLReflowMetrics desiredSize(aDesiredSize.mFlags);
desiredSize.width = desiredSize.height = 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...
nsSize kidAvailSize(aReflowState.availSize.width, NS_UNCONSTRAINEDSIZE);
nsHTMLReflowState kidReflowState(aPresContext, aReflowState.reflowState,
kidFrame, kidAvailSize,
-1, -1, PR_FALSE);
InitChildReflowState(*aPresContext, borderCollapse, kidReflowState);
// This can indicate that columns were resized.
if (aReflowState.reflowState.mFlags.mHResize)
kidReflowState.mFlags.mHResize = PR_TRUE;
// If this isn't the first row, then we can't be at the top of the page
if (kidFrame != GetFirstFrame()) {
kidReflowState.mFlags.mIsTopOfPage = PR_FALSE;
}
rv = ReflowChild(kidFrame, aPresContext, desiredSize, kidReflowState,
0, aReflowState.y, 0, aStatus);
// Place the child
PlaceChild(aPresContext, aReflowState, kidFrame, desiredSize);
aReflowState.y += cellSpacingY;
if (!reflowAllKids) {
if (IsSimpleRowFrame(aReflowState.tableFrame, kidFrame)) {
// Inform the row of its new height.
((nsTableRowFrame*)kidFrame)->DidResize();
// the overflow area may have changed inflate the overflow area
if (aReflowState.tableFrame->IsAutoHeight()) {
// Because other cells in the row may need to be aligned
// differently, repaint the entire row
nsRect kidRect(0, aReflowState.y,
desiredSize.width, desiredSize.height);
Invalidate(kidRect);
// Invalidate the area we're offseting. Note that we only
// repaint within our existing frame bounds.
if (kidRect.YMost() < mRect.height) {
nsRect dirtyRect(0, kidRect.YMost(),
mRect.width, mRect.height - kidRect.YMost());
Invalidate(dirtyRect);
}
}
else if (oldKidSize.height != desiredSize.height)
needToCalcRowHeights = PR_TRUE;
} else {
needToCalcRowHeights = PR_TRUE;
}
}
if (isPaginated && aPageBreakBeforeEnd && !*aPageBreakBeforeEnd) {
nsTableRowFrame* nextRow = ((nsTableRowFrame*)kidFrame)->GetNextRow();
if (nextRow) {
*aPageBreakBeforeEnd = nsTableFrame::PageBreakAfter(*kidFrame, nextRow);
}
}
} else {
SlideChild(aReflowState, kidFrame);
// Adjust the running y-offset so we know where the next row should be placed
nscoord height = kidFrame->GetSize().height + cellSpacingY;
aReflowState.y += height;
if (NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height) {
aReflowState.availSize.height -= height;
}
}
ConsiderChildOverflow(aDesiredSize.mOverflowArea, kidFrame);
}
if (haveRow)
aReflowState.y -= cellSpacingY;
// Return our desired rect
aDesiredSize.width = aReflowState.reflowState.availableWidth;
aDesiredSize.height = aReflowState.y;
if (aReflowState.reflowState.mFlags.mSpecialHeightReflow) {
DidResizeRows(aDesiredSize);
if (isPaginated) {
CacheRowHeightsForPrinting(aPresContext, GetFirstRow());
}
}
else if (needToCalcRowHeights) {
CalculateRowHeights(aPresContext, aDesiredSize, aReflowState.reflowState);
if (!reflowAllKids) {
// 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(dirtyRect);
}
}
return rv;
}
nsTableRowFrame*
nsTableRowGroupFrame::GetFirstRow()
{
for (nsIFrame* childFrame = GetFirstFrame(); childFrame;
childFrame = childFrame->GetNextSibling()) {
if (nsGkAtoms::tableRowFrame == childFrame->GetType()) {
return (nsTableRowFrame*)childFrame;
}
}
return nsnull;
}
struct RowInfo {
RowInfo() { height = pctHeight = hasStyleHeight = hasPctHeight = isSpecial = 0; }
unsigned height; // content height or fixed height, excluding pct height
unsigned pctHeight:29; // pct height
unsigned hasStyleHeight:1;
unsigned hasPctHeight:1;
unsigned isSpecial:1; // there is no cell originating in the row with rowspan=1 and there are at
// least 2 cells spanning the row and there is no style height on the row
};
static void
UpdateHeights(RowInfo& aRowInfo,
nscoord aAdditionalHeight,
nscoord& aTotal,
nscoord& aUnconstrainedTotal)
{
aRowInfo.height += aAdditionalHeight;
aTotal += aAdditionalHeight;
if (!aRowInfo.hasStyleHeight) {
aUnconstrainedTotal += aAdditionalHeight;
}
}
void
nsTableRowGroupFrame::DidResizeRows(nsHTMLReflowMetrics& aDesiredSize)
{
// update the cells spanning rows with their new heights
// this is the place where all of the cells in the row get set to the height of the row
// Reset the overflow area
aDesiredSize.mOverflowArea = nsRect(0, 0, 0, 0);
for (nsTableRowFrame* rowFrame = GetFirstRow();
rowFrame; rowFrame = rowFrame->GetNextRow()) {
rowFrame->DidResize();
ConsiderChildOverflow(aDesiredSize.mOverflowArea, rowFrame);
}
}
// This calculates the height of all the rows and takes into account
// style height on the row group, style heights on rows and cells, style heights on rowspans.
// Actual row heights will be adjusted later if the table has a style height.
// Even if rows don't change height, this method must be called to set the heights of each
// cell in the row to the height of its row.
void
nsTableRowGroupFrame::CalculateRowHeights(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState)
{
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (!tableFrame) return;
PRBool isPaginated = aPresContext->IsPaginated();
// all table cells have the same top and bottom margins, namely cellSpacingY
nscoord cellSpacingY = tableFrame->GetCellSpacingY();
PRInt32 numEffCols = tableFrame->GetEffectiveColCount();
PRInt32 startRowIndex = GetStartRowIndex();
// find the row corresponding to the row index we just found
nsTableRowFrame* startRowFrame = GetFirstRow();
if (!startRowFrame) return;
// the current row group height is the y origin of the 1st row we are about to calculated a height for
nscoord startRowGroupHeight = startRowFrame->GetPosition().y;
PRInt32 numRows = GetRowCount() - (startRowFrame->GetRowIndex() - GetStartRowIndex());
// collect the current height of each row. nscoord* rowHeights = nsnull;
if (numRows <= 0)
return;
nsTArray<RowInfo> rowInfo;
if (!rowInfo.AppendElements(numRows)) {
return;
}
PRBool hasRowSpanningCell = PR_FALSE;
nscoord heightOfRows = 0;
nscoord heightOfUnStyledRows = 0;
// Get the height of each row without considering rowspans. This will be the max of
// the largest desired height of each cell, the largest style height of each cell,
// the style height of the row.
nscoord pctHeightBasis = GetHeightBasis(aReflowState);
PRInt32 rowIndex; // the index in rowInfo, not among the rows in the row group
nsTableRowFrame* rowFrame;
for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
nscoord nonPctHeight = rowFrame->GetContentHeight();
if (isPaginated) {
nonPctHeight = PR_MAX(nonPctHeight, rowFrame->GetSize().height);
}
if (!rowFrame->GetPrevInFlow()) {
if (rowFrame->HasPctHeight()) {
rowInfo[rowIndex].hasPctHeight = PR_TRUE;
rowInfo[rowIndex].pctHeight = rowFrame->GetHeight(pctHeightBasis);
}
rowInfo[rowIndex].hasStyleHeight = rowFrame->HasStyleHeight();
nonPctHeight = PR_MAX(nonPctHeight, rowFrame->GetFixedHeight());
}
UpdateHeights(rowInfo[rowIndex], nonPctHeight, heightOfRows, heightOfUnStyledRows);
if (!rowInfo[rowIndex].hasStyleHeight) {
if (isPaginated || tableFrame->HasMoreThanOneCell(rowIndex + startRowIndex)) {
rowInfo[rowIndex].isSpecial = PR_TRUE;
// iteratate the row's cell frames to see if any do not have rowspan > 1
nsTableCellFrame* cellFrame = rowFrame->GetFirstCell();
while (cellFrame) {
PRInt32 rowSpan = tableFrame->GetEffectiveRowSpan(rowIndex + startRowIndex, *cellFrame);
if (1 == rowSpan) {
rowInfo[rowIndex].isSpecial = PR_FALSE;
break;
}
cellFrame = cellFrame->GetNextCell();
}
}
}
// See if a cell spans into the row. If so we'll have to do the next step
if (!hasRowSpanningCell) {
if (tableFrame->RowIsSpannedInto(rowIndex + startRowIndex, numEffCols)) {
hasRowSpanningCell = PR_TRUE;
}
}
}
if (hasRowSpanningCell) {
// Get the height of cells with rowspans and allocate any extra space to the rows they span
// iteratate the child frames and process the row frames among them
for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
// See if the row has an originating cell with rowspan > 1. We cannot determine this for a row in a
// continued row group by calling RowHasSpanningCells, because the row's fif may not have any originating
// cells yet the row may have a continued cell which originates in it.
if (GetPrevInFlow() || tableFrame->RowHasSpanningCells(startRowIndex + rowIndex, numEffCols)) {
nsTableCellFrame* cellFrame = rowFrame->GetFirstCell();
// iteratate the row's cell frames
while (cellFrame) {
PRInt32 rowSpan = tableFrame->GetEffectiveRowSpan(rowIndex + startRowIndex, *cellFrame);
if ((rowIndex + rowSpan) > numRows) {
// there might be rows pushed already to the nextInFlow
rowSpan = numRows - rowIndex;
}
if (rowSpan > 1) { // a cell with rowspan > 1, determine the height of the rows it spans
nscoord heightOfRowsSpanned = 0;
nscoord heightOfUnStyledRowsSpanned = 0;
nscoord numSpecialRowsSpanned = 0;
nscoord cellSpacingTotal = 0;
PRInt32 spanX;
for (spanX = 0; spanX < rowSpan; spanX++) {
heightOfRowsSpanned += rowInfo[rowIndex + spanX].height;
if (!rowInfo[rowIndex + spanX].hasStyleHeight) {
heightOfUnStyledRowsSpanned += rowInfo[rowIndex + spanX].height;
}
if (0 != spanX) {
cellSpacingTotal += cellSpacingY;
}
if (rowInfo[rowIndex + spanX].isSpecial) {
numSpecialRowsSpanned++;
}
}
nscoord heightOfAreaSpanned = heightOfRowsSpanned + cellSpacingTotal;
// get the height of the cell
nsSize cellFrameSize = cellFrame->GetSize();
nsSize cellDesSize = cellFrame->GetDesiredSize();
rowFrame->CalculateCellActualSize(cellFrame, cellDesSize.width,
cellDesSize.height, cellDesSize.width);
cellFrameSize.height = cellDesSize.height;
if (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 += rowFrame->GetMaxCellAscent() -
cellFrame->GetCellBaseline();
}
if (heightOfAreaSpanned < cellFrameSize.height) {
// 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 extra = cellFrameSize.height - heightOfAreaSpanned;
nscoord extraUsed = 0;
if (0 == numSpecialRowsSpanned) {
//NS_ASSERTION(heightOfRowsSpanned > 0, "invalid row span situation");
PRBool haveUnStyledRowsSpanned = (heightOfUnStyledRowsSpanned > 0);
nscoord divisor = (haveUnStyledRowsSpanned)
? heightOfUnStyledRowsSpanned : heightOfRowsSpanned;
if (divisor > 0) {
for (spanX = rowSpan - 1; spanX >= 0; spanX--) {
if (!haveUnStyledRowsSpanned || !rowInfo[rowIndex + spanX].hasStyleHeight) {
// The amount of additional space each row gets is proportional to its height
float percent = ((float)rowInfo[rowIndex + spanX].height) / ((float)divisor);
// give rows their percentage, except for the first row which gets the remainder
nscoord extraForRow = (0 == spanX) ? extra - extraUsed
: NSToCoordRound(((float)(extra)) * percent);
extraForRow = PR_MIN(extraForRow, extra - extraUsed);
// update the row height
UpdateHeights(rowInfo[rowIndex + spanX], extraForRow, heightOfRows, heightOfUnStyledRows);
extraUsed += extraForRow;
if (extraUsed >= extra) {
NS_ASSERTION((extraUsed == extra), "invalid row height calculation");
break;
}
}
}
}
else {
// put everything in the last row
UpdateHeights(rowInfo[rowIndex + rowSpan - 1], extra, heightOfRows, heightOfUnStyledRows);
}
}
else {
// give the extra to the special rows
nscoord numSpecialRowsAllocated = 0;
for (spanX = rowSpan - 1; spanX >= 0; spanX--) {
if (rowInfo[rowIndex + spanX].isSpecial) {
// The amount of additional space each degenerate row gets is proportional to the number of them
float percent = 1.0f / ((float)numSpecialRowsSpanned);
// give rows their percentage, except for the first row which gets the remainder
nscoord extraForRow = (numSpecialRowsSpanned - 1 == numSpecialRowsAllocated)
? extra - extraUsed
: NSToCoordRound(((float)(extra)) * percent);
extraForRow = PR_MIN(extraForRow, extra - extraUsed);
// update the row height
UpdateHeights(rowInfo[rowIndex + spanX], extraForRow, heightOfRows, heightOfUnStyledRows);
extraUsed += extraForRow;
if (extraUsed >= extra) {
NS_ASSERTION((extraUsed == extra), "invalid row height calculation");
break;
}
}
}
}
}
} // if (rowSpan > 1)
cellFrame = cellFrame->GetNextCell();
} // while (cellFrame)
} // if (tableFrame->RowHasSpanningCells(startRowIndex + rowIndex) {
} // while (rowFrame)
}
// pct height rows have already got their content heights. Give them their pct heights up to pctHeightBasis
nscoord extra = pctHeightBasis - heightOfRows;
for (rowFrame = startRowFrame, rowIndex = 0; rowFrame && (extra > 0); rowFrame = rowFrame->GetNextRow(), rowIndex++) {
RowInfo& rInfo = rowInfo[rowIndex];
if (rInfo.hasPctHeight) {
nscoord rowExtra = (rInfo.pctHeight > rInfo.height)
? rInfo.pctHeight - rInfo.height: 0;
rowExtra = PR_MIN(rowExtra, extra);
UpdateHeights(rInfo, rowExtra, heightOfRows, heightOfUnStyledRows);
extra -= rowExtra;
}
}
PRBool styleHeightAllocation = PR_FALSE;
nscoord rowGroupHeight = startRowGroupHeight + heightOfRows + ((numRows - 1) * cellSpacingY);
// if we have a style height, allocate the extra height to unconstrained rows
if ((aReflowState.mComputedHeight > rowGroupHeight) &&
(NS_UNCONSTRAINEDSIZE != aReflowState.mComputedHeight)) {
nscoord extraComputedHeight = aReflowState.mComputedHeight - rowGroupHeight;
nscoord extraUsed = 0;
PRBool haveUnStyledRows = (heightOfUnStyledRows > 0);
nscoord divisor = (haveUnStyledRows)
? heightOfUnStyledRows : heightOfRows;
if (divisor > 0) {
styleHeightAllocation = PR_TRUE;
for (rowIndex = 0; rowIndex < numRows; rowIndex++) {
if (!haveUnStyledRows || !rowInfo[rowIndex].hasStyleHeight) {
// The amount of additional space each row gets is based on the
// percentage of space it occupies
float percent = ((float)rowInfo[rowIndex].height) / ((float)divisor);
// give rows their percentage, except for the last row which gets the remainder
nscoord extraForRow = (numRows - 1 == rowIndex)
? extraComputedHeight - extraUsed
: NSToCoordRound(((float)extraComputedHeight) * percent);
extraForRow = PR_MIN(extraForRow, extraComputedHeight - extraUsed);
// update the row height
UpdateHeights(rowInfo[rowIndex], extraForRow, heightOfRows, heightOfUnStyledRows);
extraUsed += extraForRow;
if (extraUsed >= extraComputedHeight) {
NS_ASSERTION((extraUsed == extraComputedHeight), "invalid row height calculation");
break;
}
}
}
}
rowGroupHeight = aReflowState.mComputedHeight;
}
nscoord yOrigin = startRowGroupHeight;
// update the rows with their (potentially) new heights
for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
nsRect rowBounds = rowFrame->GetRect();
PRBool movedFrame = (rowBounds.y != yOrigin);
nscoord rowHeight = (rowInfo[rowIndex].height > 0) ? rowInfo[rowIndex].height : 0;
if (movedFrame || (rowHeight != rowBounds.height)) {
// Resize the row to its final size and position
rowBounds.y = yOrigin;
rowBounds.height = rowHeight;
rowFrame->SetRect(rowBounds);
}
if (movedFrame) {
nsTableFrame::RePositionViews(rowFrame);
}
yOrigin += rowHeight + cellSpacingY;
}
if (isPaginated && styleHeightAllocation) {
// since the row group has a style height, cache the row heights, so next in flows can honor them
CacheRowHeightsForPrinting(aPresContext, GetFirstRow());
}
DidResizeRows(aDesiredSize);
aDesiredSize.height = rowGroupHeight; // Adjust our desired size
}
nscoord
nsTableRowGroupFrame::CollapseRowGroupIfNecessary(nscoord aYTotalOffset,
nscoord aWidth)
{
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
const nsStyleVisibility* groupVis = GetStyleVisibility();
PRBool collapseGroup = (NS_STYLE_VISIBILITY_COLLAPSE == groupVis->mVisible);
if (collapseGroup) {
tableFrame->SetNeedToCollapse(PR_TRUE);
}
nsRect overflowArea(0, 0, 0, 0);
nsTableRowFrame* rowFrame= GetFirstRow();
PRBool didCollapse = PR_FALSE;
nscoord yGroupOffset = 0;
while (rowFrame) {
yGroupOffset += rowFrame->CollapseRowIfNecessary(yGroupOffset,
aWidth, collapseGroup,
didCollapse);
ConsiderChildOverflow(overflowArea, rowFrame);
rowFrame = rowFrame->GetNextRow();
}
nsRect groupRect = GetRect();
groupRect.height -= yGroupOffset;
if (didCollapse) {
// add back the cellspacing between rowgroups
groupRect.height += tableFrame->GetCellSpacingY();
}
groupRect.y -= aYTotalOffset;
groupRect.width = aWidth;
SetRect(groupRect);
overflowArea.UnionRect(nsRect(0, 0, groupRect.width, groupRect.height),
overflowArea);
FinishAndStoreOverflow(&overflowArea, nsSize(groupRect.width,
groupRect.height));
nsTableFrame::RePositionViews(this);
return yGroupOffset;
}
// Move a child that was skipped during an incremental reflow.
// 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
// XXX Is it still true that it's not used for paginated mode?
void
nsTableRowGroupFrame::SlideChild(nsRowGroupReflowState& aReflowState,
nsIFrame* aKidFrame)
{
NS_PRECONDITION(NS_UNCONSTRAINEDSIZE == aReflowState.reflowState.availableHeight,
"we're not in galley mode");
// Move the frame if we need to
nsPoint oldPosition = aKidFrame->GetPosition();
nsPoint newPosition = oldPosition;
newPosition.y = aReflowState.y;
if (oldPosition.y != newPosition.y) {
aKidFrame->SetPosition(newPosition);
nsTableFrame::RePositionViews(aKidFrame);
}
}
// Create a continuing frame, add it to the child list, and then push it
// and the frames that follow
void
nsTableRowGroupFrame::CreateContinuingRowFrame(nsPresContext& aPresContext,
nsIFrame& aRowFrame,
nsIFrame** aContRowFrame)
{
// XXX what is the row index?
if (!aContRowFrame) {NS_ASSERTION(PR_FALSE, "bad call"); return;}
// create the continuing frame which will create continuing cell frames
nsresult rv = aPresContext.PresShell()->FrameConstructor()->
CreateContinuingFrame(&aPresContext, &aRowFrame, this, aContRowFrame);
if (NS_FAILED(rv)) {
*aContRowFrame = nsnull;
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);
}
// Reflow the cells with rowspan > 1 which originate between aFirstRow
// and end on or after aLastRow. aFirstTruncatedRow is the highest row on the
// page that contains a cell which cannot split on this page
void
nsTableRowGroupFrame::SplitSpanningCells(nsPresContext& aPresContext,
const nsHTMLReflowState& aReflowState,
nsTableFrame& aTable,
nsTableRowFrame& aFirstRow,
nsTableRowFrame& aLastRow,
PRBool aFirstRowIsTopOfPage,
nscoord aAvailHeight,
nsTableRowFrame*& aContRow,
nsTableRowFrame*& aFirstTruncatedRow,
nscoord& aDesiredHeight)
{
aFirstTruncatedRow = nsnull;
aDesiredHeight = 0;
PRInt32 lastRowIndex = aLastRow.GetRowIndex();
PRBool wasLast = PR_FALSE;
// Iterate the rows between aFirstRow and aLastRow
for (nsTableRowFrame* row = &aFirstRow; !wasLast; row = row->GetNextRow()) {
wasLast = (row == &aLastRow);
PRInt32 rowIndex = row->GetRowIndex();
nsPoint rowPos = row->GetPosition();
// Iterate the cells looking for those that have rowspan > 1
for (nsTableCellFrame* cell = row->GetFirstCell(); cell; cell = cell->GetNextCell()) {
PRInt32 rowSpan = aTable.GetEffectiveRowSpan(rowIndex, *cell);
// Only reflow rowspan > 1 cells which span aLastRow. Those which don't span aLastRow
// were reflowed correctly during the unconstrained height reflow.
if ((rowSpan > 1) && (rowIndex + rowSpan > lastRowIndex)) {
nsReflowStatus status;
// Ask the row to reflow the cell to the height of all the rows it spans up through aLastRow
// aAvailHeight is the space between the row group start and the end of the page
nscoord cellAvailHeight = aAvailHeight - rowPos.y;
PRBool isTopOfPage = (row == &aFirstRow) && aFirstRowIsTopOfPage;
nscoord cellHeight = row->ReflowCellFrame(&aPresContext, aReflowState,
isTopOfPage, cell,
cellAvailHeight, status);
aDesiredHeight = PR_MAX(aDesiredHeight, rowPos.y + cellHeight);
if (NS_FRAME_IS_COMPLETE(status)) {
if (cellHeight > cellAvailHeight) {
aFirstTruncatedRow = row;
if ((row != &aFirstRow) || !aFirstRowIsTopOfPage) {
// return now, since we will be getting another reflow after either (1) row is
// moved to the next page or (2) the row group is moved to the next page
return;
}
}
}
else {
if (!aContRow) {
CreateContinuingRowFrame(aPresContext, aLastRow, (nsIFrame**)&aContRow);
}
if (aContRow) {
if (row != &aLastRow) {
// aContRow needs a continuation for cell, since cell spanned into aLastRow
// but does not originate there
nsTableCellFrame* contCell = nsnull;
aPresContext.PresShell()->FrameConstructor()->
CreateContinuingFrame(&aPresContext, cell, &aLastRow,
(nsIFrame**)&contCell);
PRInt32 colIndex;
cell->GetColIndex(colIndex);
aContRow->InsertCellFrame(contCell, colIndex);
}
}
}
}
}
}
}
// Remove the next-in-flow of the row, its cells and their cell blocks. This
// is necessary in case the row doesn't need a continuation later on or needs
// a continuation which doesn't have the same number of cells that now exist.
void
nsTableRowGroupFrame::UndoContinuedRow(nsPresContext* aPresContext,
nsTableRowFrame* aRow)
{
if (!aRow) return; // allow null aRow to avoid callers doing null checks
// rowBefore was the prev-sibling of aRow's next-sibling before aRow was created
nsTableRowFrame* rowBefore = (nsTableRowFrame*)aRow->GetPrevInFlow();
nsIFrame* firstOverflow = GetOverflowFrames(aPresContext, PR_TRUE);
if (!rowBefore || !firstOverflow || (firstOverflow != aRow)) {
NS_ASSERTION(PR_FALSE, "invalid continued row");
return;
}
// Remove aRow from the sibling chain and hook its next-sibling up with rowBefore
rowBefore->SetNextSibling(aRow->GetNextSibling());
// Destroy the row, its cells, and their cell blocks. Cell blocks that have split
// will not have reflowed yet to pick up content from any overflow lines.
aRow->Destroy();
}
static nsTableRowFrame*
GetRowBefore(nsTableRowFrame& aStartRow,
nsTableRowFrame& aRow)
{
nsTableRowFrame* rowBefore = nsnull;
for (nsTableRowFrame* sib = &aStartRow; sib && (sib != &aRow); sib = sib->GetNextRow()) {
rowBefore = sib;
}
return rowBefore;
}
nsresult
nsTableRowGroupFrame::SplitRowGroup(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsTableFrame* aTableFrame,
nsReflowStatus& aStatus)
{
NS_PRECONDITION(aPresContext->IsPaginated(), "SplitRowGroup currently supports only paged media");
nsresult rv = NS_OK;
nsTableRowFrame* prevRowFrame = nsnull;
aDesiredSize.height = 0;
nscoord availWidth = aReflowState.availableWidth;
nscoord availHeight = aReflowState.availableHeight;
PRBool borderCollapse = ((nsTableFrame*)aTableFrame->GetFirstInFlow())->IsBorderCollapse();
nscoord cellSpacingY = aTableFrame->GetCellSpacingY();
// get the page height
nscoord pageHeight = aPresContext->GetPageSize().height;
NS_ASSERTION(pageHeight != NS_UNCONSTRAINEDSIZE,
"The table shouldn't be split when there should be space");
PRBool isTopOfPage = aReflowState.mFlags.mIsTopOfPage;
nsTableRowFrame* firstRowThisPage = GetFirstRow();
// Walk each of the row frames looking for the first row frame that doesn't fit
// in the available space
for (nsTableRowFrame* rowFrame = firstRowThisPage; rowFrame; rowFrame = rowFrame->GetNextRow()) {
PRBool rowIsOnPage = PR_TRUE;
nsRect rowRect = rowFrame->GetRect();
// See if the row fits on this page
if (rowRect.YMost() > availHeight) {
nsTableRowFrame* contRow = nsnull;
// Reflow the row in the availabe space and have it split if it is the 1st
// row (on the page) or there is at least 5% of the current page available
// XXX this 5% should be made a preference
if (!prevRowFrame || (availHeight - aDesiredSize.height > pageHeight / 20)) {
nsSize availSize(availWidth, PR_MAX(availHeight - rowRect.y, 0));
// don't let the available height exceed what CalculateRowHeights set for it
availSize.height = PR_MIN(availSize.height, rowRect.height);
nsHTMLReflowState rowReflowState(aPresContext, aReflowState,
rowFrame, availSize,
-1, -1, PR_FALSE);
InitChildReflowState(*aPresContext, borderCollapse, rowReflowState);
rowReflowState.mFlags.mIsTopOfPage = isTopOfPage; // set top of page
nsHTMLReflowMetrics rowMetrics;
// Reflow the cell with the constrained height. A cell with rowspan >1 will get this
// reflow later during SplitSpanningCells.
rv = ReflowChild(rowFrame, aPresContext, rowMetrics, rowReflowState,
0, 0, NS_FRAME_NO_MOVE_FRAME, aStatus);
if (NS_FAILED(rv)) return rv;
rowFrame->SetSize(nsSize(rowMetrics.width, rowMetrics.height));
rowFrame->DidReflow(aPresContext, nsnull, NS_FRAME_REFLOW_FINISHED);
rowFrame->DidResize();
if (NS_FRAME_IS_NOT_COMPLETE(aStatus)) {
// The row frame is incomplete and all of the rowspan 1 cells' block frames split
if ((rowMetrics.height <= rowReflowState.availableHeight) || isTopOfPage) {
// The row stays on this page because either it split ok or we're on the top of page.
// If top of page and the height exceeded the avail height, then there will be data loss
NS_ASSERTION(rowMetrics.height <= rowReflowState.availableHeight,
"data loss - incomplete row needed more height than available, on top of page");
CreateContinuingRowFrame(*aPresContext, *rowFrame, (nsIFrame**)&contRow);
if (contRow) {
aDesiredSize.height += rowMetrics.height;
if (prevRowFrame)
aDesiredSize.height += cellSpacingY;
}
else return NS_ERROR_NULL_POINTER;
}
else {
// Put the row on the next page to give it more height
rowIsOnPage = PR_FALSE;
}
}
else {
// The row frame is complete because either (1) its minimum height is greater than the
// available height we gave it, or (2) it may have been given a larger height through
// style than its content, or (3) it contains a rowspan >1 cell which hasn't been
// reflowed with a constrained height yet (we will find out when SplitSpanningCells is
// called below)
if (rowMetrics.height >= availSize.height) {
// cases (1) and (2)
if (isTopOfPage) {
// We're on top of the page, so keep the row on this page. There will be data loss.
// Push the row frame that follows
nsTableRowFrame* nextRowFrame = rowFrame->GetNextRow();
if (nextRowFrame) {
aStatus = NS_FRAME_NOT_COMPLETE;
}
aDesiredSize.height += rowMetrics.height;
if (prevRowFrame)
aDesiredSize.height += cellSpacingY;
NS_WARNING("data loss - complete row needed more height than available, on top of page");
}
else {
// We're not on top of the page, so put the row on the next page to give it more height
rowIsOnPage = PR_FALSE;
}
}
}
} //if (!prevRowFrame || (availHeight - aDesiredSize.height > pageHeight / 20))
else {
// put the row on the next page to give it more height
rowIsOnPage = PR_FALSE;
}
nsTableRowFrame* lastRowThisPage = rowFrame;
if (!rowIsOnPage) {
if (prevRowFrame) {
availHeight -= prevRowFrame->GetRect().YMost();
lastRowThisPage = prevRowFrame;
isTopOfPage = (lastRowThisPage == firstRowThisPage) && aReflowState.mFlags.mIsTopOfPage;
aStatus = NS_FRAME_NOT_COMPLETE;
}
else {
// We can't push children, so let our parent reflow us again with more space
aDesiredSize.height = rowRect.YMost();
break;
}
}
// reflow the cells with rowspan >1 that occur on the page
nsTableRowFrame* firstTruncatedRow;
nscoord yMost;
SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame, *firstRowThisPage,
*lastRowThisPage, aReflowState.mFlags.mIsTopOfPage, availHeight, contRow,
firstTruncatedRow, yMost);
if (firstTruncatedRow) {
// A rowspan >1 cell did not fit (and could not split) in the space we gave it
if (firstTruncatedRow == firstRowThisPage) {
if (aReflowState.mFlags.mIsTopOfPage) {
NS_WARNING("data loss in a row spanned cell");
}
else {
// We can't push children, so let our parent reflow us again with more space
aDesiredSize.height = rowRect.YMost();
aStatus = NS_FRAME_COMPLETE;
UndoContinuedRow(aPresContext, contRow);
contRow = nsnull;
}
}
else { // (firstTruncatedRow != firstRowThisPage)
// Try to put firstTruncateRow on the next page
nsTableRowFrame* rowBefore = ::GetRowBefore(*firstRowThisPage, *firstTruncatedRow);
availHeight -= rowBefore->GetRect().YMost();
UndoContinuedRow(aPresContext, contRow);
contRow = nsnull;
nsTableRowFrame* oldLastRowThisPage = lastRowThisPage;
lastRowThisPage = firstTruncatedRow;
aStatus = NS_FRAME_NOT_COMPLETE;
// Call SplitSpanningCells again with rowBefore as the last row on the page
SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame,
*firstRowThisPage, *rowBefore, aReflowState.mFlags.mIsTopOfPage,
availHeight, contRow, firstTruncatedRow, aDesiredSize.height);
if (firstTruncatedRow) {
if (aReflowState.mFlags.mIsTopOfPage) {
// We were better off with the 1st call to SplitSpanningCells, do it again
UndoContinuedRow(aPresContext, contRow);
contRow = nsnull;
lastRowThisPage = oldLastRowThisPage;
SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame, *firstRowThisPage,
*lastRowThisPage, aReflowState.mFlags.mIsTopOfPage, availHeight, contRow,
firstTruncatedRow, aDesiredSize.height);
NS_WARNING("data loss in a row spanned cell");
}
else {
// Let our parent reflow us again with more space
aDesiredSize.height = rowRect.YMost();
aStatus = NS_FRAME_COMPLETE;
UndoContinuedRow(aPresContext, contRow);
contRow = nsnull;
}
}
} // if (firstTruncatedRow == firstRowThisPage)
} // if (firstTruncatedRow)
else {
aDesiredSize.height = PR_MAX(aDesiredSize.height, yMost);
if (contRow) {
aStatus = NS_FRAME_NOT_COMPLETE;
}
}
if (NS_FRAME_IS_NOT_COMPLETE(aStatus) && !contRow) {
nsTableRowFrame* nextRow = lastRowThisPage->GetNextRow();
if (nextRow) {
PushChildren(aPresContext, nextRow, lastRowThisPage);
}
}
break;
} // if (rowRect.YMost() > availHeight)
else {
aDesiredSize.height = rowRect.YMost();
prevRowFrame = rowFrame;
// see if there is a page break after the row
nsTableRowFrame* nextRow = rowFrame->GetNextRow();
if (nextRow && nsTableFrame::PageBreakAfter(*rowFrame, nextRow)) {
PushChildren(aPresContext, nextRow, rowFrame);
aStatus = NS_FRAME_NOT_COMPLETE;
break;
}
}
isTopOfPage = PR_FALSE; // after the 1st row, we can't be on top of the page any more.
}
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(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
DO_GLOBAL_REFLOW_COUNT("nsTableRowGroupFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
nsresult rv = NS_OK;
aStatus = NS_FRAME_COMPLETE;
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (!tableFrame) return NS_ERROR_NULL_POINTER;
// Row geometry may be going to change so we need to invalidate any row cursor.
ClearRowCursor();
// see if a special height reflow needs to occur due to having a pct height
nsTableFrame::CheckRequestSpecialHeightReflow(aReflowState);
nsRowGroupReflowState state(aReflowState, tableFrame);
const nsStyleVisibility* groupVis = GetStyleVisibility();
PRBool collapseGroup = (NS_STYLE_VISIBILITY_COLLAPSE == groupVis->mVisible);
if (collapseGroup) {
tableFrame->SetNeedToCollapse(PR_TRUE);
}
// Check for an overflow list
MoveOverflowToChildList(aPresContext);
// Reflow the existing frames.
PRBool splitDueToPageBreak = PR_FALSE;
rv = ReflowChildren(aPresContext, aDesiredSize, state, aStatus,
&splitDueToPageBreak);
// See if all the frames fit. Do not try to split anything if we're
// not paginated ... we can't split across columns yet.
if (aReflowState.mFlags.mTableIsSplittable &&
(NS_FRAME_NOT_COMPLETE == aStatus || splitDueToPageBreak ||
aDesiredSize.height > aReflowState.availableHeight)) {
// Nope, find a place to split the row group
PRBool specialReflow = (PRBool)aReflowState.mFlags.mSpecialHeightReflow;
((nsHTMLReflowState::ReflowStateFlags&)aReflowState.mFlags).mSpecialHeightReflow = PR_FALSE;
SplitRowGroup(aPresContext, aDesiredSize, aReflowState, tableFrame, aStatus);
((nsHTMLReflowState::ReflowStateFlags&)aReflowState.mFlags).mSpecialHeightReflow = specialReflow;
}
// If we have a next-in-flow, then we're not complete
// XXXldb This used to be done only for the incremental reflow codepath.
if (GetNextInFlow()) {
aStatus = NS_FRAME_NOT_COMPLETE;
}
SetHasStyleHeight((NS_UNCONSTRAINEDSIZE != aReflowState.mComputedHeight) &&
(aReflowState.mComputedHeight > 0));
// just set our width to what was available. The table will calculate the width and not use our value.
aDesiredSize.width = aReflowState.availableWidth;
// if we have a nextinflow we are not complete
if (GetNextInFlow()) {
aStatus |= NS_FRAME_NOT_COMPLETE;
}
aDesiredSize.mOverflowArea.UnionRect(aDesiredSize.mOverflowArea, nsRect(0, 0, aDesiredSize.width,
aDesiredSize.height));
FinishAndStoreOverflow(&aDesiredSize);
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
return rv;
}
NS_IMETHODIMP
nsTableRowGroupFrame::AppendFrames(nsIAtom* aListName,
nsIFrame* aFrameList)
{
NS_ASSERTION(!aListName, "unexpected child list");
ClearRowCursor();
// collect the new row frames in an array
nsAutoVoidArray rows;
for (nsIFrame* rowFrame = aFrameList; rowFrame;
rowFrame = rowFrame->GetNextSibling()) {
if (nsGkAtoms::tableRowFrame == rowFrame->GetType()) {
rows.AppendElement(rowFrame);
}
}
PRInt32 rowIndex = GetRowCount();
// Append the frames to the sibling chain
mFrames.AppendFrames(nsnull, aFrameList);
if (rows.Count() > 0) {
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (tableFrame) {
tableFrame->AppendRows(*this, rowIndex, rows);
PresContext()->PresShell()->
FrameNeedsReflow(this, nsIPresShell::eTreeChange,
NS_FRAME_HAS_DIRTY_CHILDREN);
tableFrame->SetGeometryDirty();
}
}
return NS_OK;
}
NS_IMETHODIMP
nsTableRowGroupFrame::InsertFrames(nsIAtom* aListName,
nsIFrame* aPrevFrame,
nsIFrame* aFrameList)
{
NS_ASSERTION(!aListName, "unexpected child list");
NS_ASSERTION(!aPrevFrame || aPrevFrame->GetParent() == this,
"inserting after sibling frame with different parent");
ClearRowCursor();
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (!tableFrame)
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 = rowFrame->GetNextSibling()) {
if (nsGkAtoms::tableRowFrame == rowFrame->GetType()) {
rows.AppendElement(rowFrame);
if (!gotFirstRow) {
((nsTableRowFrame*)rowFrame)->SetFirstInserted(PR_TRUE);
gotFirstRow = PR_TRUE;
tableFrame->SetRowInserted(PR_TRUE);
}
}
}
PRInt32 startRowIndex = GetStartRowIndex();
// Insert the frames in the sibling chain
mFrames.InsertFrames(nsnull, aPrevFrame, aFrameList);
PRInt32 numRows = rows.Count();
if (numRows > 0) {
nsTableRowFrame* prevRow = (nsTableRowFrame *)nsTableFrame::GetFrameAtOrBefore(this, aPrevFrame, nsGkAtoms::tableRowFrame);
PRInt32 rowIndex = (prevRow) ? prevRow->GetRowIndex() + 1 : startRowIndex;
tableFrame->InsertRows(*this, rows, rowIndex, PR_TRUE);
PresContext()->PresShell()->
FrameNeedsReflow(this, nsIPresShell::eTreeChange,
NS_FRAME_HAS_DIRTY_CHILDREN);
tableFrame->SetGeometryDirty();
}
return NS_OK;
}
NS_IMETHODIMP
nsTableRowGroupFrame::RemoveFrame(nsIAtom* aListName,
nsIFrame* aOldFrame)
{
NS_ASSERTION(!aListName, "unexpected child list");
ClearRowCursor();
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (tableFrame) {
if (nsGkAtoms::tableRowFrame == aOldFrame->GetType()) {
// remove the rows from the table (and flag a rebalance)
tableFrame->RemoveRows((nsTableRowFrame &)*aOldFrame, 1, PR_TRUE);
PresContext()->PresShell()->
FrameNeedsReflow(this, nsIPresShell::eTreeChange,
NS_FRAME_HAS_DIRTY_CHILDREN);
tableFrame->SetGeometryDirty();
}
}
mFrames.DestroyFrame(aOldFrame);
return NS_OK;
}
/* virtual */ nsMargin
nsTableRowGroupFrame::GetUsedMargin() const
{
return nsMargin(0,0,0,0);
}
/* virtual */ nsMargin
nsTableRowGroupFrame::GetUsedBorder() const
{
return nsMargin(0,0,0,0);
}
/* virtual */ nsMargin
nsTableRowGroupFrame::GetUsedPadding() const
{
return nsMargin(0,0,0,0);
}
nscoord
nsTableRowGroupFrame::GetHeightBasis(const nsHTMLReflowState& aReflowState)
{
nscoord result = 0;
nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
if (tableFrame) {
if ((aReflowState.mComputedHeight > 0) && (aReflowState.mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
nscoord cellSpacing = PR_MAX(0, GetRowCount() - 1) * tableFrame->GetCellSpacingY();
result = aReflowState.mComputedHeight - cellSpacing;
}
else {
const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
if (parentRS && (tableFrame != parentRS->frame)) {
parentRS = parentRS->parentReflowState;
}
if (parentRS && (tableFrame == parentRS->frame) &&
(parentRS->mComputedHeight > 0) && (parentRS->mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
nscoord cellSpacing = PR_MAX(0, tableFrame->GetRowCount() + 1) * tableFrame->GetCellSpacingY();
result = parentRS->mComputedHeight - cellSpacing;
}
}
}
return result;
}
PRBool
nsTableRowGroupFrame::IsSimpleRowFrame(nsTableFrame* aTableFrame,
nsIFrame* aFrame)
{
// Make sure it's a row frame and not a row group frame
if (aFrame->GetType() == nsGkAtoms::tableRowFrame) {
PRInt32 rowIndex = ((nsTableRowFrame*)aFrame)->GetRowIndex();
// It's a simple row frame if there are no cells that span into or
// across the row
PRInt32 numEffCols = aTableFrame->GetEffectiveColCount();
if (!aTableFrame->RowIsSpannedInto(rowIndex, numEffCols) &&
!aTableFrame->RowHasSpanningCells(rowIndex, numEffCols)) {
return PR_TRUE;
}
}
return PR_FALSE;
}
nsIAtom*
nsTableRowGroupFrame::GetType() const
{
return nsGkAtoms::tableRowGroupFrame;
}
/* ----- global methods ----- */
nsIFrame*
NS_NewTableRowGroupFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsTableRowGroupFrame(aContext);
}
NS_IMETHODIMP
nsTableRowGroupFrame::Init(nsIContent* aContent,
nsIFrame* aParent,
nsIFrame* aPrevInFlow)
{
// Let the base class do its processing
nsresult rv = nsHTMLContainerFrame::Init(aContent, aParent, 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(nsAString& aResult) const
{
return MakeFrameName(NS_LITERAL_STRING("TableRowGroup"), aResult);
}
#endif
nsMargin*
nsTableRowGroupFrame::GetBCBorderWidth(nsMargin& aBorder)
{
aBorder.left = aBorder.right = 0;
nsTableRowFrame* firstRowFrame = nsnull;
nsTableRowFrame* lastRowFrame = nsnull;
for (nsTableRowFrame* rowFrame = GetFirstRow(); rowFrame; rowFrame = rowFrame->GetNextRow()) {
if (!firstRowFrame) {
firstRowFrame = rowFrame;
}
lastRowFrame = rowFrame;
}
if (firstRowFrame) {
aBorder.top = nsPresContext::CSSPixelsToAppUnits(firstRowFrame->GetTopBCBorderWidth());
aBorder.bottom = nsPresContext::CSSPixelsToAppUnits(lastRowFrame->GetBottomBCBorderWidth());
}
return &aBorder;
}
void nsTableRowGroupFrame::SetContinuousBCBorderWidth(PRUint8 aForSide,
BCPixelSize aPixelValue)
{
switch (aForSide) {
case NS_SIDE_RIGHT:
mRightContBorderWidth = aPixelValue;
return;
case NS_SIDE_BOTTOM:
mBottomContBorderWidth = aPixelValue;
return;
case NS_SIDE_LEFT:
mLeftContBorderWidth = aPixelValue;
return;
default:
NS_ERROR("invalid NS_SIDE argument");
}
}
//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 = nsTableFrame::GetTableFrame(this);
if (!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->GetDataAt(aLineNumber, 0);
if (!firstCellData)
return NS_ERROR_FAILURE;
*aNumFramesOnLine = cellMap->GetNumCellsOriginatingInRow(aLineNumber);
*aFirstFrameOnLine = (nsIFrame*)firstCellData->GetCellFrame();
if (!(*aFirstFrameOnLine))
{
while((aLineNumber > 0)&&(!(*aFirstFrameOnLine)))
{
aLineNumber--;
firstCellData = cellMap->GetDataAt(aLineNumber, 0);
*aFirstFrameOnLine = (nsIFrame*)firstCellData->GetCellFrame();
}
}
if (!(*aFirstFrameOnLine)) {
NS_ERROR("Failed to find cell frame for cell data");
*aNumFramesOnLine = 0;
}
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)
if (aFrame->GetType() != nsGkAtoms::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;
*aFirstVisual = nsnull;
*aLastVisual = nsnull;
return NS_OK;
}
#endif // IBMBIDI
NS_IMETHODIMP
nsTableRowGroupFrame::FindFrameAt(PRInt32 aLineNumber,
nscoord aX,
nsIFrame** aFrameFound,
PRBool* aXIsBeforeFirstFrame,
PRBool* aXIsAfterLastFrame)
{
PRInt32 colCount = 0;
CellData* cellData;
nsIFrame* tempFrame = nsnull;
nsTableFrame* parentFrame = nsTableFrame::GetTableFrame(this);
if (!parentFrame)
return NS_ERROR_FAILURE;
nsTableCellMap* cellMap = parentFrame->GetCellMap();
if (!cellMap)
return NS_ERROR_FAILURE;
colCount = cellMap->GetColCount();
*aXIsBeforeFirstFrame = PR_FALSE;
*aXIsAfterLastFrame = PR_FALSE;
PRBool gotParentRect = PR_FALSE;
for (PRInt32 i = 0; i < colCount; i++)
{
cellData = cellMap->GetDataAt(aLineNumber, i);
if (!cellData)
continue; // we hit a cellmap hole
if (!cellData->IsOrig())
continue;
tempFrame = (nsIFrame*)cellData->GetCellFrame();
if (!tempFrame)
continue;
nsRect tempRect = tempFrame->GetRect();//offsetting x to be in row coordinates
if(!gotParentRect)
{//only do this once
nsIFrame* tempParentFrame = tempFrame->GetParent();
if(!tempParentFrame)
return NS_ERROR_FAILURE;
aX -= tempParentFrame->GetPosition().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.XMost())
{
*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 = CallQueryInterface(aFrame, &cellFrame);
if (NS_FAILED(result))
return result;
nsTableFrame* parentFrame = nsTableFrame::GetTableFrame(this);
if (!parentFrame)
return NS_ERROR_FAILURE;
nsTableCellMap* cellMap = parentFrame->GetCellMap();
if (!cellMap)
return NS_ERROR_FAILURE;
PRInt32 colIndex;
PRInt32& colIndexRef = colIndex;
cellFrame->GetColIndex(colIndexRef);
CellData* cellData = cellMap->GetDataAt(aLineNumber, colIndex + 1);
if (!cellData)// if this isn't a valid cell, drop down and check the next line
{
cellData = cellMap->GetDataAt(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->GetDataAt(aLineNumber, tempCol);
aFrame = (nsIFrame*)cellData->GetCellFrame();
if (!aFrame && (tempCol==0))
{
while ((tempRow > 0) && (!aFrame))
{
tempRow--;
cellData = cellMap->GetDataAt(tempRow, 0);
aFrame = (nsIFrame*)cellData->GetCellFrame();
}
}
}
}
return NS_OK;
}
//end nsLineIterator methods
static void
DestroyFrameCursorData(void* aObject, nsIAtom* aPropertyName,
void* aPropertyValue, void* aData)
{
delete NS_STATIC_CAST(nsTableRowGroupFrame::FrameCursorData*, aPropertyValue);
}
void
nsTableRowGroupFrame::ClearRowCursor()
{
if (!(GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR))
return;
RemoveStateBits(NS_ROWGROUP_HAS_ROW_CURSOR);
DeleteProperty(nsGkAtoms::rowCursorProperty);
}
nsTableRowGroupFrame::FrameCursorData*
nsTableRowGroupFrame::SetupRowCursor()
{
if (GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR) {
// We already have a valid row cursor. Don't waste time rebuilding it.
return nsnull;
}
nsIFrame* f = mFrames.FirstChild();
PRInt32 count;
for (count = 0; f && count < MIN_ROWS_NEEDING_CURSOR; ++count) {
f = f->GetNextSibling();
}
if (!f) {
// Less than MIN_ROWS_NEEDING_CURSOR rows, so just don't bother
return nsnull;
}
FrameCursorData* data = new FrameCursorData();
if (!data)
return nsnull;
nsresult rv = SetProperty(nsGkAtoms::rowCursorProperty, data,
DestroyFrameCursorData);
if (NS_FAILED(rv)) {
delete data;
return nsnull;
}
AddStateBits(NS_ROWGROUP_HAS_ROW_CURSOR);
return data;
}
nsIFrame*
nsTableRowGroupFrame::GetFirstRowContaining(nscoord aY, nscoord* aOverflowAbove)
{
if (!(GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR))
return nsnull;
FrameCursorData* property = NS_STATIC_CAST(FrameCursorData*,
GetProperty(nsGkAtoms::rowCursorProperty));
PRUint32 cursorIndex = property->mCursorIndex;
PRUint32 frameCount = property->mFrames.Length();
if (cursorIndex >= frameCount)
return nsnull;
nsIFrame* cursorFrame = property->mFrames[cursorIndex];
// The cursor's frame list excludes frames with empty overflow-area, so
// we don't need to check that here.
// We use property->mOverflowBelow here instead of computing the frame's
// true overflowArea.YMost(), because it is essential for the thresholds
// to form a monotonically increasing sequence. Otherwise we would break
// encountering a row whose overflowArea.YMost() is <= aY but which has
// a row above it containing cell(s) that span to include aY.
while (cursorIndex > 0 &&
cursorFrame->GetRect().YMost() + property->mOverflowBelow > aY) {
--cursorIndex;
cursorFrame = property->mFrames[cursorIndex];
}
while (cursorIndex + 1 < frameCount &&
cursorFrame->GetRect().YMost() + property->mOverflowBelow <= aY) {
++cursorIndex;
cursorFrame = property->mFrames[cursorIndex];
}
property->mCursorIndex = cursorIndex;
*aOverflowAbove = property->mOverflowAbove;
return cursorFrame;
}
PRBool
nsTableRowGroupFrame::FrameCursorData::AppendFrame(nsIFrame* aFrame)
{
nsRect overflowRect = aFrame->GetOverflowRect();
if (overflowRect.IsEmpty())
return PR_TRUE;
nscoord overflowAbove = -overflowRect.y;
nscoord overflowBelow = overflowRect.YMost() - aFrame->GetSize().height;
mOverflowAbove = PR_MAX(mOverflowAbove, overflowAbove);
mOverflowBelow = PR_MAX(mOverflowBelow, overflowBelow);
return mFrames.AppendElement(aFrame) != nsnull;
}