bool
nsColumnSetFrame::ReflowChildren(nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus,
const ReflowConfig& aConfig,
bool aUnboundedLastColumn,
nsCollapsingMargin* aCarriedOutBEndMargin,
ColumnBalanceData& aColData)
{
aColData.Reset();
bool allFit = true;
WritingMode wm = GetWritingMode();
bool isVertical = wm.IsVertical();
bool isRTL = !wm.IsBidiLTR();
bool shrinkingBSizeOnly = !NS_SUBTREE_DIRTY(this) &&
mLastBalanceBSize > aConfig.mColMaxBSize;
#ifdef DEBUG_roc
printf("*** Doing column reflow pass: mLastBalanceBSize=%d, mColMaxBSize=%d, RTL=%d\n"
" mBalanceColCount=%d, mColISize=%d, mColGap=%d\n",
mLastBalanceBSize, aConfig.mColMaxBSize, isRTL, aConfig.mBalanceColCount,
aConfig.mColISize, aConfig.mColGap);
#endif
DrainOverflowColumns();
const bool colBSizeChanged = mLastBalanceBSize != aConfig.mColMaxBSize;
if (colBSizeChanged) {
mLastBalanceBSize = aConfig.mColMaxBSize;
// XXX Seems like this could fire if incremental reflow pushed the column set
// down so we reflow incrementally with a different available height.
// We need a way to do an incremental reflow and be sure availableHeight
// changes are taken account of! Right now I think block frames with absolute
// children might exit early.
//NS_ASSERTION(aKidReason != eReflowReason_Incremental,
// "incremental reflow should not have changed the balance height");
}
// get our border and padding
LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
borderPadding.ApplySkipSides(GetLogicalSkipSides(&aReflowState));
nsRect contentRect(0, 0, 0, 0);
nsOverflowAreas overflowRects;
nsIFrame* child = mFrames.FirstChild();
LogicalPoint childOrigin(wm, borderPadding.IStart(wm),
borderPadding.BStart(wm));
// In vertical-rl mode, columns will not be correctly placed if the
// reflowState's ComputedWidth() is UNCONSTRAINED (in which case we'll get
// a containerSize.width of zero here). In that case, the column positions
// will be adjusted later, after our correct contentSize is known.
nsSize containerSize = aReflowState.ComputedSizeAsContainerIfConstrained();
// For RTL, since the columns might not fill the frame exactly, we
// need to account for the slop. Otherwise we'll waste time moving the
// columns by some tiny amount
// XXX when all of layout is converted to logical coordinates, we
// probably won't need to do this hack any more. For now, we
// confine it to the legacy horizontal-rl case
if (!isVertical && isRTL) {
nscoord availISize = aReflowState.AvailableISize();
if (aReflowState.ComputedISize() != NS_INTRINSICSIZE) {
availISize = aReflowState.ComputedISize();
}
if (availISize != NS_INTRINSICSIZE) {
childOrigin.I(wm) = containerSize.width - borderPadding.Left(wm) -
availISize;
#ifdef DEBUG_roc
printf("*** childOrigin.iCoord = %d\n", childOrigin.I(wm));
#endif
}
}
int columnCount = 0;
int contentBEnd = 0;
bool reflowNext = false;
while (child) {
// Try to skip reflowing the child. We can't skip if the child is dirty. We also can't
// skip if the next column is dirty, because the next column's first line(s)
// might be pullable back to this column. We can't skip if it's the last child
// because we need to obtain the bottom margin. We can't skip
// if this is the last column and we're supposed to assign unbounded
// height to it, because that could change the available height from
// the last time we reflowed it and we should try to pull all the
// content from its next sibling. (Note that it might be the last
// column, but not be the last child because the desired number of columns
// has changed.)
bool skipIncremental = !aReflowState.ShouldReflowAllKids()
&& !NS_SUBTREE_DIRTY(child)
&& child->GetNextSibling()
&& !(aUnboundedLastColumn && columnCount == aConfig.mBalanceColCount - 1)
&& !NS_SUBTREE_DIRTY(child->GetNextSibling());
// If we need to pull up content from the prev-in-flow then this is not just
// a height shrink. The prev in flow will have set the dirty bit.
// Check the overflow rect YMost instead of just the child's content height. The child
// may have overflowing content that cares about the available height boundary.
// (It may also have overflowing content that doesn't care about the available height
// boundary, but if so, too bad, this optimization is defeated.)
// We want scrollable overflow here since this is a calculation that
// affects layout.
bool skipResizeBSizeShrink = false;
if (shrinkingBSizeOnly) {
switch (wm.GetBlockDir()) {
case WritingMode::eBlockTB:
if (child->GetScrollableOverflowRect().YMost() <= aConfig.mColMaxBSize) {
skipResizeBSizeShrink = true;
}
break;
case WritingMode::eBlockLR:
if (child->GetScrollableOverflowRect().XMost() <= aConfig.mColMaxBSize) {
skipResizeBSizeShrink = true;
}
break;
case WritingMode::eBlockRL:
// XXX not sure how to handle this, so for now just don't attempt
// the optimization
break;
default:
NS_NOTREACHED("unknown block direction");
break;
}
}
nscoord childContentBEnd = 0;
if (!reflowNext && (skipIncremental || skipResizeBSizeShrink)) {
// This child does not need to be reflowed, but we may need to move it
MoveChildTo(child, childOrigin, wm, containerSize);
// If this is the last frame then make sure we get the right status
nsIFrame* kidNext = child->GetNextSibling();
if (kidNext) {
aStatus = (kidNext->GetStateBits() & NS_FRAME_IS_OVERFLOW_CONTAINER)
? NS_FRAME_OVERFLOW_INCOMPLETE
: NS_FRAME_NOT_COMPLETE;
} else {
aStatus = mLastFrameStatus;
}
childContentBEnd = nsLayoutUtils::CalculateContentBEnd(wm, child);
#ifdef DEBUG_roc
printf("*** Skipping child #%d %p (incremental %d, resize block-size shrink %d): status = %d\n",
columnCount, (void*)child, skipIncremental, skipResizeBSizeShrink, aStatus);
#endif
} else {
LogicalSize availSize(wm, aConfig.mColISize, aConfig.mColMaxBSize);
if (aUnboundedLastColumn && columnCount == aConfig.mBalanceColCount - 1) {
availSize.BSize(wm) = GetAvailableContentBSize(aReflowState);
}
LogicalSize computedSize = aReflowState.ComputedSize(wm);
if (reflowNext)
child->AddStateBits(NS_FRAME_IS_DIRTY);
LogicalSize kidCBSize(wm, availSize.ISize(wm), computedSize.BSize(wm));
nsHTMLReflowState kidReflowState(PresContext(), aReflowState, child,
availSize, &kidCBSize);
kidReflowState.mFlags.mIsTopOfPage = true;
kidReflowState.mFlags.mTableIsSplittable = false;
kidReflowState.mFlags.mIsColumnBalancing = aConfig.mBalanceColCount < INT32_MAX;
// We need to reflow any float placeholders, even if our column height
// hasn't changed.
kidReflowState.mFlags.mMustReflowPlaceholders = !colBSizeChanged;
#ifdef DEBUG_roc
printf("*** Reflowing child #%d %p: availHeight=%d\n",
columnCount, (void*)child,availSize.BSize(wm));
#endif
// Note if the column's next in flow is not being changed by this incremental reflow.
// This may allow the current column to avoid trying to pull lines from the next column.
if (child->GetNextSibling() &&
!(GetStateBits() & NS_FRAME_IS_DIRTY) &&
!(child->GetNextSibling()->GetStateBits() & NS_FRAME_IS_DIRTY)) {
kidReflowState.mFlags.mNextInFlowUntouched = true;
}
nsHTMLReflowMetrics kidDesiredSize(wm, aDesiredSize.mFlags);
// XXX it would be cool to consult the float manager for the
// previous block to figure out the region of floats from the
// previous column that extend into this column, and subtract
// that region from the new float manager. So you could stick a
// really big float in the first column and text in following
// columns would flow around it.
// Reflow the frame
LogicalPoint origin(wm,
childOrigin.I(wm) +
kidReflowState.ComputedLogicalMargin().IStart(wm),
childOrigin.B(wm) +
kidReflowState.ComputedLogicalMargin().BStart(wm));
ReflowChild(child, PresContext(), kidDesiredSize, kidReflowState,
wm, origin, containerSize, 0, aStatus);
reflowNext = (aStatus & NS_FRAME_REFLOW_NEXTINFLOW) != 0;
#ifdef DEBUG_roc
printf("*** Reflowed child #%d %p: status = %d, desiredSize=%d,%d CarriedOutBEndMargin=%d\n",
columnCount, (void*)child, aStatus, kidDesiredSize.Width(), kidDesiredSize.Height(),
kidDesiredSize.mCarriedOutBEndMargin.get());
#endif
NS_FRAME_TRACE_REFLOW_OUT("Column::Reflow", aStatus);
*aCarriedOutBEndMargin = kidDesiredSize.mCarriedOutBEndMargin;
FinishReflowChild(child, PresContext(), kidDesiredSize,
&kidReflowState, wm, childOrigin, containerSize, 0);
childContentBEnd = nsLayoutUtils::CalculateContentBEnd(wm, child);
if (childContentBEnd > aConfig.mColMaxBSize) {
allFit = false;
}
if (childContentBEnd > availSize.BSize(wm)) {
aColData.mMaxOverflowingBSize = std::max(childContentBEnd,
aColData.mMaxOverflowingBSize);
}
}
contentRect.UnionRect(contentRect, child->GetRect());
ConsiderChildOverflow(overflowRects, child);
contentBEnd = std::max(contentBEnd, childContentBEnd);
aColData.mLastBSize = childContentBEnd;
aColData.mSumBSize += childContentBEnd;
// Build a continuation column if necessary
nsIFrame* kidNextInFlow = child->GetNextInFlow();
if (NS_FRAME_IS_FULLY_COMPLETE(aStatus) && !NS_FRAME_IS_TRUNCATED(aStatus)) {
NS_ASSERTION(!kidNextInFlow, "next in flow should have been deleted");
child = nullptr;
break;
} else {
++columnCount;
// Make sure that the column has a next-in-flow. If not, we must
// create one to hold the overflowing stuff, even if we're just
// going to put it on our overflow list and let *our*
// next in flow handle it.
if (!kidNextInFlow) {
NS_ASSERTION(aStatus & NS_FRAME_REFLOW_NEXTINFLOW,
"We have to create a continuation, but the block doesn't want us to reflow it?");
// We need to create a continuing column
kidNextInFlow = CreateNextInFlow(child);
}
// Make sure we reflow a next-in-flow when it switches between being
// normal or overflow container
if (NS_FRAME_OVERFLOW_IS_INCOMPLETE(aStatus)) {
if (!(kidNextInFlow->GetStateBits() & NS_FRAME_IS_OVERFLOW_CONTAINER)) {
aStatus |= NS_FRAME_REFLOW_NEXTINFLOW;
reflowNext = true;
kidNextInFlow->AddStateBits(NS_FRAME_IS_OVERFLOW_CONTAINER);
}
}
else if (kidNextInFlow->GetStateBits() & NS_FRAME_IS_OVERFLOW_CONTAINER) {
aStatus |= NS_FRAME_REFLOW_NEXTINFLOW;
reflowNext = true;
kidNextInFlow->RemoveStateBits(NS_FRAME_IS_OVERFLOW_CONTAINER);
}
if ((contentBEnd > aReflowState.ComputedMaxBSize() ||
contentBEnd > aReflowState.ComputedBSize()) &&
aConfig.mBalanceColCount < INT32_MAX) {
// We overflowed vertically, but have not exceeded the number of
// columns. We're going to go into overflow columns now, so balancing
// no longer applies.
aColData.mHasExcessBSize = true;
}
if (columnCount >= aConfig.mBalanceColCount) {
// No more columns allowed here. Stop.
aStatus |= NS_FRAME_REFLOW_NEXTINFLOW;
kidNextInFlow->AddStateBits(NS_FRAME_IS_DIRTY);
// Move any of our leftover columns to our overflow list. Our
// next-in-flow will eventually pick them up.
const nsFrameList& continuationColumns = mFrames.RemoveFramesAfter(child);
if (continuationColumns.NotEmpty()) {
SetOverflowFrames(continuationColumns);
}
child = nullptr;
break;
}
}
if (PresContext()->HasPendingInterrupt()) {
// Stop the loop now while |child| still points to the frame that bailed
// out. We could keep going here and condition a bunch of the code in
// this loop on whether there's an interrupt, or even just keep going and
// trying to reflow the blocks (even though we know they'll interrupt
// right after their first line), but stopping now is conceptually the
// simplest (and probably fastest) thing.
break;
}
// Advance to the next column
child = child->GetNextSibling();
if (child) {
childOrigin.I(wm) += aConfig.mColISize + aConfig.mColGap;
#ifdef DEBUG_roc
printf("*** NEXT CHILD ORIGIN.icoord = %d\n", childOrigin.I(wm));
#endif
}
}
if (PresContext()->CheckForInterrupt(this) &&
(GetStateBits() & NS_FRAME_IS_DIRTY)) {
// Mark all our kids starting with |child| dirty
// Note that this is a CheckForInterrupt call, not a HasPendingInterrupt,
// because we might have interrupted while reflowing |child|, and since
// we're about to add a dirty bit to |child| we need to make sure that
// |this| is scheduled to have dirty bits marked on it and its ancestors.
// Otherwise, when we go to mark dirty bits on |child|'s ancestors we'll
// bail out immediately, since it'll already have a dirty bit.
for (; child; child = child->GetNextSibling()) {
child->AddStateBits(NS_FRAME_IS_DIRTY);
}
}
aColData.mMaxBSize = contentBEnd;
LogicalSize contentSize = LogicalSize(wm, contentRect.Size());
contentSize.BSize(wm) = std::max(contentSize.BSize(wm), contentBEnd);
mLastFrameStatus = aStatus;
// Apply computed and min/max values
if (aConfig.mComputedBSize != NS_INTRINSICSIZE) {
if (aReflowState.AvailableBSize() != NS_INTRINSICSIZE) {
contentSize.BSize(wm) = std::min(contentSize.BSize(wm),
aConfig.mComputedBSize);
} else {
contentSize.BSize(wm) = aConfig.mComputedBSize;
}
} else {
// We add the "consumed" block-size back in so that we're applying
// constraints to the correct bSize value, then subtract it again
// after we've finished with the min/max calculation. This prevents us from
// having a last continuation that is smaller than the min bSize. but which
// has prev-in-flows, trigger a larger bSize than actually required.
contentSize.BSize(wm) =
aReflowState.ApplyMinMaxBSize(contentSize.BSize(wm),
aConfig.mConsumedBSize);
}
if (aReflowState.ComputedISize() != NS_INTRINSICSIZE) {
contentSize.ISize(wm) = aReflowState.ComputedISize();
} else {
contentSize.ISize(wm) =
aReflowState.ApplyMinMaxISize(contentSize.ISize(wm));
}
contentSize.ISize(wm) += borderPadding.IStartEnd(wm);
contentSize.BSize(wm) += borderPadding.BStartEnd(wm);
aDesiredSize.SetSize(wm, contentSize);
aDesiredSize.mOverflowAreas = overflowRects;
aDesiredSize.UnionOverflowAreasWithDesiredBounds();
// In vertical-rl mode, make a second pass if necessary to reposition the
// columns with the correct container width. (In other writing modes,
// correct containerSize was not required for column positioning so we don't
// need this fixup.)
if (wm.IsVerticalRL() && containerSize.width != contentSize.Width(wm)) {
const nsSize finalContainerSize = aDesiredSize.PhysicalSize();
for (nsIFrame* child : mFrames) {
// Get the logical position as set previously using a provisional or
// dummy containerSize, and reset with the correct container size.
child->SetPosition(wm, child->GetLogicalPosition(wm, containerSize),
finalContainerSize);
}
}
#ifdef DEBUG_roc
printf("*** DONE PASS feasible=%d\n", allFit && NS_FRAME_IS_FULLY_COMPLETE(aStatus)
&& !NS_FRAME_IS_TRUNCATED(aStatus));
#endif
return allFit && NS_FRAME_IS_FULLY_COMPLETE(aStatus)
&& !NS_FRAME_IS_TRUNCATED(aStatus);
}
