C++ nsHTMLReflowMetrics::UnionOverflowAreasWithDesiredBounds方法代码示例

NS_IMETHODIMP
nsFirstLetterFrame::Reflow(nsPresContext*          aPresContext,
                           nsHTMLReflowMetrics&     aMetrics,
                           const nsHTMLReflowState& aReflowState,
                           nsReflowStatus&          aReflowStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsFirstLetterFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aReflowStatus);
  nsresult rv = NS_OK;

  // Grab overflow list
  DrainOverflowFrames(aPresContext);

  nsIFrame* kid = mFrames.FirstChild();

  // Setup reflow state for our child
  nsSize availSize(aReflowState.availableWidth, aReflowState.availableHeight);
  const nsMargin& bp = aReflowState.mComputedBorderPadding;
  nscoord lr = bp.left + bp.right;
  nscoord tb = bp.top + bp.bottom;
  NS_ASSERTION(availSize.width != NS_UNCONSTRAINEDSIZE,
               "should no longer use unconstrained widths");
  availSize.width -= lr;
  if (NS_UNCONSTRAINEDSIZE != availSize.height) {
    availSize.height -= tb;
  }

  // Reflow the child
  if (!aReflowState.mLineLayout) {
    // When there is no lineLayout provided, we provide our own. The
    // only time that the first-letter-frame is not reflowing in a
    // line context is when its floating.
    nsHTMLReflowState rs(aPresContext, aReflowState, kid, availSize);
    nsLineLayout ll(aPresContext, nullptr, &aReflowState, nullptr);

    // For unicode-bidi: plaintext, we need to get the direction of the line
    // from the resolved paragraph level of the child, not the block frame,
    // because the block frame could be split by hard line breaks into
    // multiple paragraphs with different base direction
    PRUint8 direction;
    nsIFrame* containerFrame = ll.GetLineContainerFrame();
    if (containerFrame->GetStyleTextReset()->mUnicodeBidi &
        NS_STYLE_UNICODE_BIDI_PLAINTEXT) {
      FramePropertyTable *propTable = aPresContext->PropertyTable();
      direction = NS_PTR_TO_INT32(propTable->Get(kid, BaseLevelProperty())) & 1;
    } else {
      direction = containerFrame->GetStyleVisibility()->mDirection;
    }
    ll.BeginLineReflow(bp.left, bp.top, availSize.width, NS_UNCONSTRAINEDSIZE,
                       false, true, direction);
    rs.mLineLayout = ≪
    ll.SetInFirstLetter(true);
    ll.SetFirstLetterStyleOK(true);

    kid->WillReflow(aPresContext);
    kid->Reflow(aPresContext, aMetrics, rs, aReflowStatus);

    ll.EndLineReflow();
    ll.SetInFirstLetter(false);

    // In the floating first-letter case, we need to set this ourselves;
    // nsLineLayout::BeginSpan will set it in the other case
    mBaseline = aMetrics.ascent;
  }
  else {
    // Pretend we are a span and reflow the child frame
    nsLineLayout* ll = aReflowState.mLineLayout;
    bool          pushedFrame;

    ll->SetInFirstLetter(
      mStyleContext->GetPseudo() == nsCSSPseudoElements::firstLetter);
    ll->BeginSpan(this, &aReflowState, bp.left, availSize.width, &mBaseline);
    ll->ReflowFrame(kid, aReflowStatus, &aMetrics, pushedFrame);
    ll->EndSpan(this);
    ll->SetInFirstLetter(false);
  }

  // Place and size the child and update the output metrics
  kid->SetRect(nsRect(bp.left, bp.top, aMetrics.width, aMetrics.height));
  kid->FinishAndStoreOverflow(&aMetrics);
  kid->DidReflow(aPresContext, nullptr, NS_FRAME_REFLOW_FINISHED);

  aMetrics.width += lr;
  aMetrics.height += tb;
  aMetrics.ascent += bp.top;

  // Ensure that the overflow rect contains the child textframe's overflow rect.
  // Note that if this is floating, the overline/underline drawable area is in
  // the overflow rect of the child textframe.
  aMetrics.UnionOverflowAreasWithDesiredBounds();
  ConsiderChildOverflow(aMetrics.mOverflowAreas, kid);

  if (!NS_INLINE_IS_BREAK_BEFORE(aReflowStatus)) {
    // Create a continuation or remove existing continuations based on
    // the reflow completion status.
    if (NS_FRAME_IS_COMPLETE(aReflowStatus)) {
      if (aReflowState.mLineLayout) {
        aReflowState.mLineLayout->SetFirstLetterStyleOK(false);
      }
      nsIFrame* kidNextInFlow = kid->GetNextInFlow();
//.........这里部分代码省略.........

//.........这里部分代码省略.........
        }
        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);
}