C++ nsHTMLReflowMetrics::BSize方法代码示例

/* virtual */ void
nsRubyTextContainerFrame::Reflow(nsPresContext* aPresContext,
                                 nsHTMLReflowMetrics& aDesiredSize,
                                 const nsHTMLReflowState& aReflowState,
                                 nsReflowStatus& aStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsRubyTextContainerFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);

  // All rt children have already been reflowed. All we need to do is clean up
  // the line layout.

  aStatus = NS_FRAME_COMPLETE;
  mozilla::WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
  mozilla::WritingMode frameWM = aReflowState.GetWritingMode();
  mozilla::LogicalMargin borderPadding =
    aReflowState.ComputedLogicalBorderPadding();

  aDesiredSize.ISize(lineWM) = mISize;
  nsLayoutUtils::SetBSizeFromFontMetrics(this, aDesiredSize, aReflowState,
                                         borderPadding, lineWM, frameWM);

  nscoord bsize = aDesiredSize.BSize(lineWM);
  if (!mLines.empty()) {
    // Okay to use BlockStartAscent because it has just been correctly set by
    // nsLayoutUtils::SetBSizeFromFontMetrics.
    mLines.begin()->SetLogicalAscent(aDesiredSize.BlockStartAscent());
    mLines.begin()->SetBounds(aReflowState.GetWritingMode(), 0, 0, mISize,
                              bsize, mISize);
  }

  if (mLineLayout) {
    mLineLayout->EndLineReflow();
    mLineLayout = nullptr;
  }
}

void
nsTableCellFrame::Reflow(nsPresContext*           aPresContext,
                         nsHTMLReflowMetrics&     aDesiredSize,
                         const nsHTMLReflowState& aReflowState,
                         nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsTableCellFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);

  if (aReflowState.mFlags.mSpecialBSizeReflow) {
    FirstInFlow()->AddStateBits(NS_TABLE_CELL_HAD_SPECIAL_REFLOW);
  }

  // see if a special bsize reflow needs to occur due to having a pct height
  nsTableFrame::CheckRequestSpecialBSizeReflow(aReflowState);

  aStatus = NS_FRAME_COMPLETE;
  WritingMode wm = aReflowState.GetWritingMode();
  LogicalSize availSize(wm, aReflowState.AvailableISize(),
                            aReflowState.AvailableBSize());

  LogicalMargin borderPadding = aReflowState.ComputedLogicalPadding();
  LogicalMargin border = GetBorderWidth(wm);
  borderPadding += border;

  // reduce available space by insets, if we're in a constrained situation
  availSize.ISize(wm) -= borderPadding.IStartEnd(wm);
  if (NS_UNCONSTRAINEDSIZE != availSize.BSize(wm)) {
    availSize.BSize(wm) -= borderPadding.BStartEnd(wm);
  }

  // Try to reflow the child into the available space. It might not
  // fit or might need continuing.
  if (availSize.BSize(wm) < 0) {
    availSize.BSize(wm) = 1;
  }

  nsHTMLReflowMetrics kidSize(wm, aDesiredSize.mFlags);
  kidSize.ClearSize();
  SetPriorAvailISize(aReflowState.AvailableISize());
  nsIFrame* firstKid = mFrames.FirstChild();
  NS_ASSERTION(firstKid, "Frame construction error, a table cell always has an inner cell frame");
  nsTableFrame* tableFrame = GetTableFrame();

  if (aReflowState.mFlags.mSpecialBSizeReflow) {
    const_cast<nsHTMLReflowState&>(aReflowState).
      SetComputedBSize(BSize(wm) - borderPadding.BStartEnd(wm));
    DISPLAY_REFLOW_CHANGE();
  }
  else if (aPresContext->IsPaginated()) {
    nscoord computedUnpaginatedBSize =
      CalcUnpaginatedBSize(aPresContext, (nsTableCellFrame&)*this,
                           *tableFrame, borderPadding.BStartEnd(wm));
    if (computedUnpaginatedBSize > 0) {
      const_cast<nsHTMLReflowState&>(aReflowState).SetComputedBSize(computedUnpaginatedBSize);
      DISPLAY_REFLOW_CHANGE();
    }
  }
  else {
    SetHasPctOverBSize(false);
  }

  WritingMode kidWM = firstKid->GetWritingMode();
  nsHTMLReflowState kidReflowState(aPresContext, aReflowState, firstKid,
                                   availSize.ConvertTo(kidWM, wm));

  // Don't be a percent height observer if we're in the middle of
  // special-bsize reflow, in case we get an accidental NotifyPercentBSize()
  // call (which we shouldn't honor during special-bsize reflow)
  if (!aReflowState.mFlags.mSpecialBSizeReflow) {
    // mPercentBSizeObserver is for children of cells in quirks mode,
    // but only those than are tables in standards mode.  NeedsToObserve
    // will determine how far this is propagated to descendants.
    kidReflowState.mPercentBSizeObserver = this;
  }
  // Don't propagate special bsize reflow state to our kids
  kidReflowState.mFlags.mSpecialBSizeReflow = false;

  if (aReflowState.mFlags.mSpecialBSizeReflow ||
      FirstInFlow()->HasAnyStateBits(NS_TABLE_CELL_HAD_SPECIAL_REFLOW)) {
    // We need to force the kid to have mBResize set if we've had a
    // special reflow in the past, since the non-special reflow needs to
    // resize back to what it was without the special bsize reflow.
    kidReflowState.SetBResize(true);
  }

  nsSize containerSize =
    aReflowState.ComputedSizeAsContainerIfConstrained();

  LogicalPoint kidOrigin(wm, borderPadding.IStart(wm),
                         borderPadding.BStart(wm));
  nsRect origRect = firstKid->GetRect();
  nsRect origVisualOverflow = firstKid->GetVisualOverflowRect();
  bool firstReflow = firstKid->HasAnyStateBits(NS_FRAME_FIRST_REFLOW);

  ReflowChild(firstKid, aPresContext, kidSize, kidReflowState,
              wm, kidOrigin, containerSize, 0, aStatus);
  if (NS_FRAME_OVERFLOW_IS_INCOMPLETE(aStatus)) {
    // Don't pass OVERFLOW_INCOMPLETE through tables until they can actually handle it
//.........这里部分代码省略.........

void
nsPageContentFrame::Reflow(nsPresContext*           aPresContext,
                           nsHTMLReflowMetrics&     aDesiredSize,
                           const nsHTMLReflowState& aReflowState,
                           nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsPageContentFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  aStatus = NS_FRAME_COMPLETE;  // initialize out parameter

  if (GetPrevInFlow() && (GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
    nsresult rv = aPresContext->PresShell()->FrameConstructor()
                    ->ReplicateFixedFrames(this);
    if (NS_FAILED(rv)) {
      return;
    }
  }

  // Set our size up front, since some parts of reflow depend on it
  // being already set.  Note that the computed height may be
  // unconstrained; that's ok.  Consumers should watch out for that.
  nsSize  maxSize(aReflowState.ComputedWidth(),
                  aReflowState.ComputedHeight());
  SetSize(maxSize);
 
  // A PageContentFrame must always have one child: the canvas frame.
  // Resize our frame allowing it only to be as big as we are
  // XXX Pay attention to the page's border and padding...
  if (mFrames.NotEmpty()) {
    nsIFrame* frame = mFrames.FirstChild();
    WritingMode wm = frame->GetWritingMode();
    LogicalSize logicalSize(wm, maxSize);
    nsHTMLReflowState kidReflowState(aPresContext, aReflowState,
                                     frame, logicalSize);
    kidReflowState.SetComputedBSize(logicalSize.BSize(wm));

    // Reflow the page content area
    ReflowChild(frame, aPresContext, aDesiredSize, kidReflowState, 0, 0, 0, aStatus);

    // The document element's background should cover the entire canvas, so
    // take into account the combined area and any space taken up by
    // absolutely positioned elements
    nsMargin padding(0,0,0,0);

    // XXXbz this screws up percentage padding (sets padding to zero
    // in the percentage padding case)
    kidReflowState.mStylePadding->GetPadding(padding);

    // This is for shrink-to-fit, and therefore we want to use the
    // scrollable overflow, since the purpose of shrink to fit is to
    // make the content that ought to be reachable (represented by the
    // scrollable overflow) fit in the page.
    if (frame->HasOverflowAreas()) {
      // The background covers the content area and padding area, so check
      // for children sticking outside the child frame's padding edge
      nscoord xmost = aDesiredSize.ScrollableOverflow().XMost();
      if (xmost > aDesiredSize.Width()) {
        nscoord widthToFit = xmost + padding.right +
          kidReflowState.mStyleBorder->GetComputedBorderWidth(NS_SIDE_RIGHT);
        float ratio = float(maxSize.width) / widthToFit;
        NS_ASSERTION(ratio >= 0.0 && ratio < 1.0, "invalid shrink-to-fit ratio");
        mPD->mShrinkToFitRatio = std::min(mPD->mShrinkToFitRatio, ratio);
      }
    }

    // Place and size the child
    FinishReflowChild(frame, aPresContext, aDesiredSize, &kidReflowState, 0, 0, 0);

    NS_ASSERTION(aPresContext->IsDynamic() || !NS_FRAME_IS_FULLY_COMPLETE(aStatus) ||
                  !frame->GetNextInFlow(), "bad child flow list");
  }

  // Reflow our fixed frames
  nsReflowStatus fixedStatus = NS_FRAME_COMPLETE;
  ReflowAbsoluteFrames(aPresContext, aDesiredSize, aReflowState, fixedStatus);
  NS_ASSERTION(NS_FRAME_IS_COMPLETE(fixedStatus), "fixed frames can be truncated, but not incomplete");

  // Return our desired size
  WritingMode wm = aReflowState.GetWritingMode();
  aDesiredSize.ISize(wm) = aReflowState.ComputedISize();
  if (aReflowState.ComputedBSize() != NS_UNCONSTRAINEDSIZE) {
    aDesiredSize.BSize(wm) = aReflowState.ComputedBSize();
  }
  FinishAndStoreOverflow(&aDesiredSize);

  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
}

void
BRFrame::Reflow(nsPresContext* aPresContext,
                nsHTMLReflowMetrics& aMetrics,
                const nsHTMLReflowState& aReflowState,
                nsReflowStatus& aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("BRFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aStatus);
  WritingMode wm = aReflowState.GetWritingMode();
  LogicalSize finalSize(wm);
  finalSize.BSize(wm) = 0; // BR frames with block size 0 are ignored in quirks
                           // mode by nsLineLayout::VerticalAlignFrames .
                           // However, it's not always 0.  See below.
  finalSize.ISize(wm) = 0;
  aMetrics.SetBlockStartAscent(0);

  // Only when the BR is operating in a line-layout situation will it
  // behave like a BR. Additionally, we suppress breaks from BR inside
  // of ruby frames. To determine if we're inside ruby, we have to rely
  // on the *parent's* ShouldSuppressLineBreak() method, instead of our
  // own, because we may have custom "display" value that makes our
  // ShouldSuppressLineBreak() return false.
  nsLineLayout* ll = aReflowState.mLineLayout;
  if (ll && !GetParent()->StyleContext()->ShouldSuppressLineBreak()) {
    // Note that the compatibility mode check excludes AlmostStandards
    // mode, since this is the inline box model.  See bug 161691.
    if ( ll->LineIsEmpty() ||
         aPresContext->CompatibilityMode() == eCompatibility_FullStandards ) {
      // The line is logically empty; any whitespace is trimmed away.
      //
      // If this frame is going to terminate the line we know
      // that nothing else will go on the line. Therefore, in this
      // case, we provide some height for the BR frame so that it
      // creates some vertical whitespace.  It's necessary to use the
      // line-height rather than the font size because the
      // quirks-mode fix that doesn't apply the block's min
      // line-height makes this necessary to make BR cause a line
      // of the full line-height

      // We also do this in strict mode because BR should act like a
      // normal inline frame.  That line-height is used is important
      // here for cases where the line-height is less than 1.
      RefPtr<nsFontMetrics> fm =
        nsLayoutUtils::GetInflatedFontMetricsForFrame(this);
      if (fm) {
        nscoord logicalHeight = aReflowState.CalcLineHeight();
        finalSize.BSize(wm) = logicalHeight;
        aMetrics.SetBlockStartAscent(nsLayoutUtils::GetCenteredFontBaseline(
                                       fm, logicalHeight, wm.IsLineInverted()));
      }
      else {
        aMetrics.SetBlockStartAscent(aMetrics.BSize(wm) = 0);
      }

      // XXX temporary until I figure out a better solution; see the
      // code in nsLineLayout::VerticalAlignFrames that zaps minY/maxY
      // if the width is zero.
      // XXX This also fixes bug 10036!
      // Warning: nsTextControlFrame::CalculateSizeStandard depends on
      // the following line, see bug 228752.
      // The code below in AddInlinePrefISize also adds 1 appunit to width
      finalSize.ISize(wm) = 1;
    }

    // Return our reflow status
    uint32_t breakType = aReflowState.mStyleDisplay->PhysicalBreakType(wm);
    if (NS_STYLE_CLEAR_NONE == breakType) {
      breakType = NS_STYLE_CLEAR_LINE;
    }

    aStatus = NS_INLINE_BREAK | NS_INLINE_BREAK_AFTER |
      NS_INLINE_MAKE_BREAK_TYPE(breakType);
    ll->SetLineEndsInBR(true);
  }
  else {
    aStatus = NS_FRAME_COMPLETE;
  }

  aMetrics.SetSize(wm, finalSize);
  aMetrics.SetOverflowAreasToDesiredBounds();

  mAscent = aMetrics.BlockStartAscent();

  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aMetrics);
}

void
nsMathMLmtableOuterFrame::Reflow(nsPresContext*          aPresContext,
                                 nsHTMLReflowMetrics&     aDesiredSize,
                                 const nsHTMLReflowState& aReflowState,
                                 nsReflowStatus&          aStatus)
{
  nsAutoString value;
  // we want to return a table that is anchored according to the align attribute

  nsTableOuterFrame::Reflow(aPresContext, aDesiredSize, aReflowState, aStatus);
  NS_ASSERTION(aDesiredSize.Height() >= 0, "illegal height for mtable");
  NS_ASSERTION(aDesiredSize.Width() >= 0, "illegal width for mtable");

  // see if the user has set the align attribute on the <mtable>
  int32_t rowIndex = 0;
  eAlign tableAlign = eAlign_axis;
  mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::align, value);
  if (!value.IsEmpty()) {
    ParseAlignAttribute(value, tableAlign, rowIndex);
  }

  // adjustments if there is a specified row from where to anchor the table
  // (conceptually: when there is no row of reference, picture the table as if
  // it is wrapped in a single big fictional row at dy = 0, this way of
  // doing so allows us to have a single code path for all cases).
  nscoord dy = 0;
  WritingMode wm = aDesiredSize.GetWritingMode();
  nscoord blockSize = aDesiredSize.BSize(wm);
  nsIFrame* rowFrame = nullptr;
  if (rowIndex) {
    rowFrame = GetRowFrameAt(rowIndex);
    if (rowFrame) {
      // translate the coordinates to be relative to us and in our writing mode
      nsIFrame* frame = rowFrame;
      LogicalRect rect(wm, frame->GetRect(),
                       aReflowState.ComputedSizeAsContainerIfConstrained());
      blockSize = rect.BSize(wm);
      do {
        dy += rect.BStart(wm);
        frame = frame->GetParent();
      } while (frame != this);
    }
  }
  switch (tableAlign) {
    case eAlign_top:
      aDesiredSize.SetBlockStartAscent(dy);
      break;
    case eAlign_bottom:
      aDesiredSize.SetBlockStartAscent(dy + blockSize);
      break;
    case eAlign_center:
      aDesiredSize.SetBlockStartAscent(dy + blockSize / 2);
      break;
    case eAlign_baseline:
      if (rowFrame) {
        // anchor the table on the baseline of the row of reference
        nscoord rowAscent = ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent();
        if (rowAscent) { // the row has at least one cell with 'vertical-align: baseline'
          aDesiredSize.SetBlockStartAscent(dy + rowAscent);
          break;
        }
      }
      // in other situations, fallback to center
      aDesiredSize.SetBlockStartAscent(dy + blockSize / 2);
      break;
    case eAlign_axis:
    default: {
      // XXX should instead use style data from the row of reference here ?
      RefPtr<nsFontMetrics> fm;
      nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm),
                                            nsLayoutUtils::
                                            FontSizeInflationFor(this));
      nscoord axisHeight;
      GetAxisHeight(aReflowState.rendContext->GetDrawTarget(), fm, axisHeight);
      if (rowFrame) {
        // anchor the table on the axis of the row of reference
        // XXX fallback to baseline because it is a hard problem
        // XXX need to fetch the axis of the row; would need rowalign=axis to work better
        nscoord rowAscent = ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent();
        if (rowAscent) { // the row has at least one cell with 'vertical-align: baseline'
          aDesiredSize.SetBlockStartAscent(dy + rowAscent);
          break;
        }
      }
      // in other situations, fallback to using half of the height
      aDesiredSize.SetBlockStartAscent(dy + blockSize / 2 + axisHeight);
    }
  }

  mReference.x = 0;
  mReference.y = aDesiredSize.BlockStartAscent();

  // just make-up a bounding metrics
  mBoundingMetrics = nsBoundingMetrics();
  mBoundingMetrics.ascent = aDesiredSize.BlockStartAscent();
  mBoundingMetrics.descent = aDesiredSize.Height() -
                             aDesiredSize.BlockStartAscent();
  mBoundingMetrics.width = aDesiredSize.Width();
  mBoundingMetrics.leftBearing = 0;
  mBoundingMetrics.rightBearing = aDesiredSize.Width();
//.........这里部分代码省略.........