C++ nsHTMLReflowState::ComputedPhysicalBorderPadding方法代码示例

void
nsSubDocumentFrame::Reflow(nsPresContext*           aPresContext,
                           nsHTMLReflowMetrics&     aDesiredSize,
                           const nsHTMLReflowState& aReflowState,
                           nsReflowStatus&          aStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsSubDocumentFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  // printf("OuterFrame::Reflow %X (%d,%d) \n", this, aReflowState.AvailableWidth(), aReflowState.AvailableHeight());
  NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
     ("enter nsSubDocumentFrame::Reflow: maxSize=%d,%d",
      aReflowState.AvailableWidth(), aReflowState.AvailableHeight()));

  aStatus = NS_FRAME_COMPLETE;

  NS_ASSERTION(mContent->GetPrimaryFrame() == this,
               "Shouldn't happen");

  // XUL <iframe> or <browser>, or HTML <iframe>, <object> or <embed>
  nsLeafFrame::DoReflow(aPresContext, aDesiredSize, aReflowState, aStatus);

  // "offset" is the offset of our content area from our frame's
  // top-left corner.
  nsPoint offset = nsPoint(aReflowState.ComputedPhysicalBorderPadding().left,
                           aReflowState.ComputedPhysicalBorderPadding().top);

  nsSize innerSize(aDesiredSize.Width(), aDesiredSize.Height());
  innerSize.width  -= aReflowState.ComputedPhysicalBorderPadding().LeftRight();
  innerSize.height -= aReflowState.ComputedPhysicalBorderPadding().TopBottom();

  if (mInnerView) {
    nsViewManager* vm = mInnerView->GetViewManager();
    vm->MoveViewTo(mInnerView, offset.x, offset.y);
    vm->ResizeView(mInnerView, nsRect(nsPoint(0, 0), innerSize), true);
  }

  aDesiredSize.SetOverflowAreasToDesiredBounds();
  if (!ShouldClipSubdocument()) {
    nsIFrame* subdocRootFrame = GetSubdocumentRootFrame();
    if (subdocRootFrame) {
      aDesiredSize.mOverflowAreas.UnionWith(subdocRootFrame->GetOverflowAreas() + offset);
    }
  }

  FinishAndStoreOverflow(&aDesiredSize);

  if (!aPresContext->IsPaginated() && !mPostedReflowCallback) {
    PresContext()->PresShell()->PostReflowCallback(this);
    mPostedReflowCallback = true;
  }

  // printf("OuterFrame::Reflow DONE %X (%d,%d)\n", this,
  //        aDesiredSize.Width(), aDesiredSize.Height());

  NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
     ("exit nsSubDocumentFrame::Reflow: size=%d,%d status=%x",
      aDesiredSize.Width(), aDesiredSize.Height(), aStatus));

  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
}

// XXX how should border&padding effect baseline alignment?
// => descent = borderPadding.bottom for example
void
nsLeafFrame::AddBordersAndPadding(const nsHTMLReflowState& aReflowState,
                                  nsHTMLReflowMetrics& aMetrics)
{
  aMetrics.Width() += aReflowState.ComputedPhysicalBorderPadding().LeftRight();
  aMetrics.Height() += aReflowState.ComputedPhysicalBorderPadding().TopBottom();
}

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

  NS_ASSERTION(mTrackDiv, "::-moz-range-track div must exist!");
  NS_ASSERTION(mProgressDiv, "::-moz-range-progress div must exist!");
  NS_ASSERTION(mThumbDiv, "::-moz-range-thumb div must exist!");
  NS_ASSERTION(!GetPrevContinuation() && !GetNextContinuation(),
               "nsRangeFrame should not have continuations; if it does we "
               "need to call RegUnregAccessKey only for the first.");

  if (mState & NS_FRAME_FIRST_REFLOW) {
    nsFormControlFrame::RegUnRegAccessKey(this, true);
  }

  nscoord computedHeight = aReflowState.ComputedHeight();
  if (computedHeight == NS_AUTOHEIGHT) {
    computedHeight = 0;
  }
  aDesiredSize.Width() = aReflowState.ComputedWidth() +
                       aReflowState.ComputedPhysicalBorderPadding().LeftRight();
  aDesiredSize.Height() = computedHeight +
                        aReflowState.ComputedPhysicalBorderPadding().TopBottom();

  ReflowAnonymousContent(aPresContext, aDesiredSize, aReflowState);

  aDesiredSize.SetOverflowAreasToDesiredBounds();

  nsIFrame* trackFrame = mTrackDiv->GetPrimaryFrame();
  if (trackFrame) {
    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, trackFrame);
  }

  nsIFrame* rangeProgressFrame = mProgressDiv->GetPrimaryFrame();
  if (rangeProgressFrame) {
    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, rangeProgressFrame);
  }

  nsIFrame* thumbFrame = mThumbDiv->GetPrimaryFrame();
  if (thumbFrame) {
    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, thumbFrame);
  }

  FinishAndStoreOverflow(&aDesiredSize);

  aStatus = NS_FRAME_COMPLETE;

  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
}

nscoord
nsColumnSetFrame::GetAvailableContentHeight(const nsHTMLReflowState& aReflowState)
{
  if (aReflowState.AvailableHeight() == NS_INTRINSICSIZE) {
    return NS_INTRINSICSIZE;
  }

  nsMargin bp = aReflowState.ComputedPhysicalBorderPadding();
  bp.ApplySkipSides(GetSkipSides(&aReflowState));
  bp.bottom = aReflowState.ComputedPhysicalBorderPadding().bottom;
  return std::max(0, aReflowState.AvailableHeight() - bp.TopBottom());
}

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

  // make sure that the form registers itself on the initial/first reflow
  if (mState & NS_FRAME_FIRST_REFLOW) {
    nsFormControlFrame::RegUnRegAccessKey(this, true);
  }

  // set values of reflow's out parameters
  aDesiredSize.Width() = aReflowState.ComputedWidth() +
                       aReflowState.ComputedPhysicalBorderPadding().LeftRight();
  aDesiredSize.Height() = aReflowState.ComputedHeight() +
                        aReflowState.ComputedPhysicalBorderPadding().TopBottom();

  // computation of the ascent wrt the input height
  nscoord lineHeight = aReflowState.ComputedHeight();
  float inflation = nsLayoutUtils::FontSizeInflationFor(this);
  if (!IsSingleLineTextControl()) {
    lineHeight = nsHTMLReflowState::CalcLineHeight(StyleContext(), 
                                                  NS_AUTOHEIGHT, inflation);
  }
  nsRefPtr<nsFontMetrics> fontMet;
  nsresult rv = nsLayoutUtils::GetFontMetricsForFrame(this, 
                                                      getter_AddRefs(fontMet), 
                                                      inflation);
  NS_ENSURE_SUCCESS(rv, rv);
  // now adjust for our borders and padding
  aDesiredSize.SetTopAscent( 
        nsLayoutUtils::GetCenteredFontBaseline(fontMet, lineHeight) 
        + aReflowState.ComputedPhysicalBorderPadding().top);

  // overflow handling
  aDesiredSize.SetOverflowAreasToDesiredBounds();
  // perform reflow on all kids
  nsIFrame* kid = mFrames.FirstChild();
  while (kid) {
    ReflowTextControlChild(kid, aPresContext, aReflowState, aStatus, aDesiredSize);
    kid = kid->GetNextSibling();
  }

  // take into account css properties that affect overflow handling
  FinishAndStoreOverflow(&aDesiredSize);

  aStatus = NS_FRAME_COMPLETE;
  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
  return NS_OK;
}

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

  if (IsFrameTreeTooDeep(aReflowState, aDesiredSize, aStatus)) {
    return;
  }

  nsMargin bp = aReflowState.ComputedPhysicalBorderPadding();
  ApplySkipSides(bp);
  nscoord contentHeight = GetEffectiveComputedHeight(aReflowState);
  if (contentHeight == NS_AUTOHEIGHT) {
    contentHeight = 0;
  }
  aDesiredSize.Width() = aReflowState.ComputedWidth() + bp.LeftRight();
  aDesiredSize.Height() = contentHeight + bp.TopBottom();
  aDesiredSize.SetOverflowAreasToDesiredBounds();
  aStatus = NS_FRAME_COMPLETE;
  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
}

void
nsTextControlFrame::ReflowTextControlChild(nsIFrame*                aKid,
                                           nsPresContext*           aPresContext,
                                           const nsHTMLReflowState& aReflowState,
                                           nsReflowStatus&          aStatus,
                                           nsHTMLReflowMetrics& aParentDesiredSize)
{
  // compute available size and frame offsets for child
  nsSize availSize(aReflowState.ComputedWidth(), 
                   aReflowState.ComputedHeight());
  availSize.width = std::max(availSize.width, 0);
  availSize.height = std::max(availSize.height, 0);
  
  nsHTMLReflowState kidReflowState(aPresContext, aReflowState, 
                                   aKid, availSize);

  // Set computed width and computed height for the child
  nscoord width = availSize.width;
  width -= kidReflowState.ComputedPhysicalMargin().LeftRight() +
              kidReflowState.ComputedPhysicalBorderPadding().LeftRight();
  width = std::max(width, 0);
  kidReflowState.SetComputedWidth(width);

  nscoord height = availSize.height;
  height -= kidReflowState.ComputedPhysicalMargin().TopBottom() +
              kidReflowState.ComputedPhysicalBorderPadding().TopBottom();
  height = std::max(height, 0);       
  kidReflowState.SetComputedHeight(height); 

  // compute the offsets
  nscoord xOffset = aReflowState.ComputedPhysicalBorderPadding().left
                      + kidReflowState.ComputedPhysicalMargin().left;
  nscoord yOffset = aReflowState.ComputedPhysicalBorderPadding().top
                      + kidReflowState.ComputedPhysicalMargin().top;

  // reflow the child
  nsHTMLReflowMetrics desiredSize(aReflowState.GetWritingMode());
  ReflowChild(aKid, aPresContext, desiredSize, kidReflowState, 
              xOffset, yOffset, 0, aStatus);

  // place the child
  FinishReflowChild(aKid, aPresContext, &kidReflowState, 
                    desiredSize, xOffset, yOffset, 0);

  // consider the overflow
  aParentDesiredSize.mOverflowAreas.UnionWith(desiredSize.mOverflowAreas);
}

void
nsMeterFrame::ReflowBarFrame(nsIFrame*                aBarFrame,
                             nsPresContext*           aPresContext,
                             const nsHTMLReflowState& aReflowState,
                             nsReflowStatus&          aStatus)
{
  bool vertical = ResolvedOrientationIsVertical();
  WritingMode wm = aBarFrame->GetWritingMode();
  LogicalSize availSize = aReflowState.ComputedSize(wm);
  availSize.BSize(wm) = NS_UNCONSTRAINEDSIZE;
  nsHTMLReflowState reflowState(aPresContext, aReflowState,
                                aBarFrame, availSize);
  nscoord size = vertical ? aReflowState.ComputedHeight()
                          : aReflowState.ComputedWidth();
  nscoord xoffset = aReflowState.ComputedPhysicalBorderPadding().left;
  nscoord yoffset = aReflowState.ComputedPhysicalBorderPadding().top;

  // NOTE: Introduce a new function getPosition in the content part ?
  HTMLMeterElement* meterElement = static_cast<HTMLMeterElement*>(mContent);

  double max = meterElement->Max();
  double min = meterElement->Min();
  double value = meterElement->Value();

  double position = max - min;
  position = position != 0 ? (value - min) / position : 1;

  size = NSToCoordRound(size * position);

  if (!vertical && (wm.IsVertical() ? wm.IsVerticalRL() : !wm.IsBidiLTR())) {
    xoffset += aReflowState.ComputedWidth() - size;
  }

  // The bar position is *always* constrained.
  if (vertical) {
    // We want the bar to begin at the bottom.
    yoffset += aReflowState.ComputedHeight() - size;

    size -= reflowState.ComputedPhysicalMargin().TopBottom() +
            reflowState.ComputedPhysicalBorderPadding().TopBottom();
    size = std::max(size, 0);
    reflowState.SetComputedHeight(size);
  } else {
    size -= reflowState.ComputedPhysicalMargin().LeftRight() +
            reflowState.ComputedPhysicalBorderPadding().LeftRight();
    size = std::max(size, 0);
    reflowState.SetComputedWidth(size);
  }

  xoffset += reflowState.ComputedPhysicalMargin().left;
  yoffset += reflowState.ComputedPhysicalMargin().top;

  nsHTMLReflowMetrics barDesiredSize(reflowState);
  ReflowChild(aBarFrame, aPresContext, barDesiredSize, reflowState, xoffset,
              yoffset, 0, aStatus);
  FinishReflowChild(aBarFrame, aPresContext, barDesiredSize, &reflowState,
                    xoffset, yoffset, 0);
}

void
nsTextControlFrame::ReflowTextControlChild(nsIFrame*                aKid,
                                           nsPresContext*           aPresContext,
                                           const nsHTMLReflowState& aReflowState,
                                           nsReflowStatus&          aStatus,
                                           nsHTMLReflowMetrics& aParentDesiredSize)
{
  // compute available size and frame offsets for child
  WritingMode wm = aKid->GetWritingMode();
  LogicalSize availSize = aReflowState.ComputedSizeWithPadding(wm);
  availSize.BSize(wm) = NS_UNCONSTRAINEDSIZE;

  nsHTMLReflowState kidReflowState(aPresContext, aReflowState, 
                                   aKid, availSize, nullptr,
                                   nsHTMLReflowState::CALLER_WILL_INIT);
  // Override padding with our computed padding in case we got it from theming or percentage
  kidReflowState.Init(aPresContext, nullptr, nullptr, &aReflowState.ComputedPhysicalPadding());

  // Set computed width and computed height for the child
  kidReflowState.SetComputedWidth(aReflowState.ComputedWidth());
  kidReflowState.SetComputedHeight(aReflowState.ComputedHeight());

  // Offset the frame by the size of the parent's border
  nscoord xOffset = aReflowState.ComputedPhysicalBorderPadding().left -
                    aReflowState.ComputedPhysicalPadding().left;
  nscoord yOffset = aReflowState.ComputedPhysicalBorderPadding().top -
                    aReflowState.ComputedPhysicalPadding().top;

  // reflow the child
  nsHTMLReflowMetrics desiredSize(aReflowState);
  ReflowChild(aKid, aPresContext, desiredSize, kidReflowState, 
              xOffset, yOffset, 0, aStatus);

  // place the child
  FinishReflowChild(aKid, aPresContext, desiredSize,
                    &kidReflowState, xOffset, yOffset, 0);

  // consider the overflow
  aParentDesiredSize.mOverflowAreas.UnionWith(desiredSize.mOverflowAreas);
}

void
nsHTMLButtonControlFrame::ReflowButtonContents(nsPresContext* aPresContext,
                                               nsHTMLReflowMetrics& aButtonDesiredSize,
                                               const nsHTMLReflowState& aButtonReflowState,
                                               nsIFrame* aFirstKid)
{
  // Buttons have some bonus renderer-determined border/padding,
  // which occupies part of the button's content-box area:
  const nsMargin focusPadding = mRenderer.GetAddedButtonBorderAndPadding();

  WritingMode wm = aFirstKid->GetWritingMode();
  LogicalSize availSize = aButtonReflowState.ComputedSize(GetWritingMode());
  availSize.BSize(wm) = NS_INTRINSICSIZE;

  // Indent the child inside us by the focus border. We must do this separate
  // from the regular border.
  availSize.ISize(wm) -= LogicalMargin(wm, focusPadding).IStartEnd(wm);

  // See whether out availSize's width is big enough.  If it's smaller than our
  // intrinsic min width, that means that the kid wouldn't really fit; for a
  // better look in such cases we adjust the available width and our left
  // offset to allow the kid to spill left into our padding.
  nscoord xoffset = focusPadding.left +
    aButtonReflowState.ComputedPhysicalBorderPadding().left;
  nscoord extrawidth = GetMinISize(aButtonReflowState.rendContext) -
    aButtonReflowState.ComputedWidth();
  if (extrawidth > 0) {
    nscoord extraleft = extrawidth / 2;
    nscoord extraright = extrawidth - extraleft;
    NS_ASSERTION(extraright >=0, "How'd that happen?");

    // Do not allow the extras to be bigger than the relevant padding
    extraleft = std::min(extraleft, aButtonReflowState.ComputedPhysicalPadding().left);
    extraright = std::min(extraright, aButtonReflowState.ComputedPhysicalPadding().right);
    xoffset -= extraleft;
    availSize.Width(wm) = availSize.Width(wm) + extraleft + extraright;
  }
  availSize.Width(wm) = std::max(availSize.Width(wm), 0);

  // Give child a clone of the button's reflow state, with height/width reduced
  // by focusPadding, so that descendants with height:100% don't protrude.
  nsHTMLReflowState adjustedButtonReflowState =
    CloneReflowStateWithReducedContentBox(aButtonReflowState, focusPadding);

  nsHTMLReflowState contentsReflowState(aPresContext,
                                        adjustedButtonReflowState,
                                        aFirstKid, availSize);

  nsReflowStatus contentsReflowStatus;
  nsHTMLReflowMetrics contentsDesiredSize(aButtonReflowState);
  ReflowChild(aFirstKid, aPresContext,
              contentsDesiredSize, contentsReflowState,
              xoffset,
              focusPadding.top + aButtonReflowState.ComputedPhysicalBorderPadding().top,
              0, contentsReflowStatus);
  MOZ_ASSERT(NS_FRAME_IS_COMPLETE(contentsReflowStatus),
             "We gave button-contents frame unconstrained available height, "
             "so it should be complete");

  // Compute the button's content-box height:
  nscoord buttonContentBoxHeight = 0;
  if (aButtonReflowState.ComputedHeight() != NS_INTRINSICSIZE) {
    // Button has a fixed height -- that's its content-box height.
    buttonContentBoxHeight = aButtonReflowState.ComputedHeight();
  } else {
    // Button is intrinsically sized -- it should shrinkwrap the
    // button-contents' height, plus any focus-padding space:
    buttonContentBoxHeight =
      contentsDesiredSize.Height() + focusPadding.TopBottom();

    // Make sure we obey min/max-height in the case when we're doing intrinsic
    // sizing (we get it for free when we have a non-intrinsic
    // aButtonReflowState.ComputedHeight()).  Note that we do this before
    // adjusting for borderpadding, since mComputedMaxHeight and
    // mComputedMinHeight are content heights.
    buttonContentBoxHeight =
      NS_CSS_MINMAX(buttonContentBoxHeight,
                    aButtonReflowState.ComputedMinHeight(),
                    aButtonReflowState.ComputedMaxHeight());
  }

  // Center child vertically in the button
  // (technically, inside of the button's focus-padding area)
  nscoord extraSpace =
    buttonContentBoxHeight - focusPadding.TopBottom() -
    contentsDesiredSize.Height();

  nscoord yoffset = std::max(0, extraSpace / 2);

  // Adjust yoffset to be in terms of the button's frame-rect, instead of
  // its focus-padding rect:
  yoffset += focusPadding.top + aButtonReflowState.ComputedPhysicalBorderPadding().top;

  // Place the child
  FinishReflowChild(aFirstKid, aPresContext,
                    contentsDesiredSize, &contentsReflowState,
                    xoffset, yoffset, 0);

  // Make sure we have a useful 'ascent' value for the child
  if (contentsDesiredSize.BlockStartAscent() ==
//.........这里部分代码省略.........

nsresult
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.ComputedPhysicalBorderPadding();
  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);

    ll.BeginLineReflow(bp.left, bp.top, availSize.width, NS_UNCONSTRAINEDSIZE,
                       false, true,
                       ll.LineContainerFrame()->GetWritingMode(kid),
                       aReflowState.AvailableWidth());
    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.TopAscent();
  }
  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, nsDidReflowStatus::FINISHED);

  aMetrics.Width() += lr;
  aMetrics.Height() += tb;
  aMetrics.SetTopAscent(aMetrics.TopAscent() + 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();
      if (kidNextInFlow) {
        // Remove all of the childs next-in-flows
        static_cast<nsContainerFrame*>(kidNextInFlow->GetParent())
          ->DeleteNextInFlowChild(kidNextInFlow, true);
      }
    }
    else {
      // Create a continuation for the child frame if it doesn't already
      // have one.
      if (!IsFloating()) {
        nsIFrame* nextInFlow;
//.........这里部分代码省略.........

void
nsSubDocumentFrame::Reflow(nsPresContext*           aPresContext,
                           nsHTMLReflowMetrics&     aDesiredSize,
                           const nsHTMLReflowState& aReflowState,
                           nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsSubDocumentFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
     ("enter nsSubDocumentFrame::Reflow: maxSize=%d,%d",
      aReflowState.AvailableWidth(), aReflowState.AvailableHeight()));

  NS_ASSERTION(aReflowState.ComputedWidth() != NS_UNCONSTRAINEDSIZE,
               "Shouldn't have unconstrained stuff here "
               "thanks to the rules of reflow");
  NS_ASSERTION(NS_INTRINSICSIZE != aReflowState.ComputedHeight(),
               "Shouldn't have unconstrained stuff here "
               "thanks to ComputeAutoSize");

  aStatus = NS_FRAME_COMPLETE;

  NS_ASSERTION(mContent->GetPrimaryFrame() == this,
               "Shouldn't happen");

  // XUL <iframe> or <browser>, or HTML <iframe>, <object> or <embed>
  aDesiredSize.SetSize(aReflowState.GetWritingMode(),
                       aReflowState.ComputedSizeWithBorderPadding());

  // "offset" is the offset of our content area from our frame's
  // top-left corner.
  nsPoint offset = nsPoint(aReflowState.ComputedPhysicalBorderPadding().left,
                           aReflowState.ComputedPhysicalBorderPadding().top);

  if (mInnerView) {
    const nsMargin& bp = aReflowState.ComputedPhysicalBorderPadding();
    nsSize innerSize(aDesiredSize.Width() - bp.LeftRight(),
                     aDesiredSize.Height() - bp.TopBottom());

    // Size & position the view according to 'object-fit' & 'object-position'.
    nsIFrame* subDocRoot = ObtainIntrinsicSizeFrame();
    IntrinsicSize intrinsSize;
    nsSize intrinsRatio;
    if (subDocRoot) {
      intrinsSize = subDocRoot->GetIntrinsicSize();
      intrinsRatio = subDocRoot->GetIntrinsicRatio();
    }
    nsRect destRect =
      nsLayoutUtils::ComputeObjectDestRect(nsRect(offset, innerSize),
                                           intrinsSize, intrinsRatio,
                                           StylePosition());

    nsViewManager* vm = mInnerView->GetViewManager();
    vm->MoveViewTo(mInnerView, destRect.x, destRect.y);
    vm->ResizeView(mInnerView, nsRect(nsPoint(0, 0), destRect.Size()), true);
  }

  aDesiredSize.SetOverflowAreasToDesiredBounds();
  if (!ShouldClipSubdocument()) {
    nsIFrame* subdocRootFrame = GetSubdocumentRootFrame();
    if (subdocRootFrame) {
      aDesiredSize.mOverflowAreas.UnionWith(subdocRootFrame->GetOverflowAreas() + offset);
    }
  }

  FinishAndStoreOverflow(&aDesiredSize);

  if (!aPresContext->IsPaginated() && !mPostedReflowCallback) {
    PresContext()->PresShell()->PostReflowCallback(this);
    mPostedReflowCallback = true;
  }

  NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
     ("exit nsSubDocumentFrame::Reflow: size=%d,%d status=%x",
      aDesiredSize.Width(), aDesiredSize.Height(), aStatus));

  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
}

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

  NS_ASSERTION(mOuterWrapper, "Outer wrapper div must exist!");

  NS_ASSERTION(!GetPrevContinuation() && !GetNextContinuation(),
               "nsNumberControlFrame should not have continuations; if it does we "
               "need to call RegUnregAccessKey only for the first");

  NS_ASSERTION(!mFrames.FirstChild() ||
               !mFrames.FirstChild()->GetNextSibling(),
               "We expect at most one direct child frame");

  if (mState & NS_FRAME_FIRST_REFLOW) {
    nsFormControlFrame::RegUnRegAccessKey(this, true);
  }

  // The width of our content box, which is the available width
  // for our anonymous content:
  const nscoord contentBoxWidth = aReflowState.ComputedWidth();
  nscoord contentBoxHeight = aReflowState.ComputedHeight();

  nsIFrame* outerWrapperFrame = mOuterWrapper->GetPrimaryFrame();

  if (!outerWrapperFrame) { // display:none?
    if (contentBoxHeight == NS_INTRINSICSIZE) {
      contentBoxHeight = 0;
    }
  } else {
    NS_ASSERTION(outerWrapperFrame == mFrames.FirstChild(), "huh?");

    nsHTMLReflowMetrics wrappersDesiredSize(aReflowState);

    WritingMode wm = outerWrapperFrame->GetWritingMode();
    LogicalSize availSize = aReflowState.ComputedSize(wm);
    availSize.BSize(wm) = NS_UNCONSTRAINEDSIZE;

    nsHTMLReflowState wrapperReflowState(aPresContext, aReflowState,
                                         outerWrapperFrame, availSize);

    // offsets of wrapper frame
    nscoord xoffset = aReflowState.ComputedPhysicalBorderPadding().left +
                        wrapperReflowState.ComputedPhysicalMargin().left;
    nscoord yoffset = aReflowState.ComputedPhysicalBorderPadding().top +
                        wrapperReflowState.ComputedPhysicalMargin().top;

    nsReflowStatus childStatus;
    ReflowChild(outerWrapperFrame, aPresContext, wrappersDesiredSize,
                wrapperReflowState, xoffset, yoffset, 0, childStatus);
    MOZ_ASSERT(NS_FRAME_IS_FULLY_COMPLETE(childStatus),
               "We gave our child unconstrained height, so it should be complete");

    nscoord wrappersMarginBoxHeight = wrappersDesiredSize.Height() +
      wrapperReflowState.ComputedPhysicalMargin().TopBottom();

    if (contentBoxHeight == NS_INTRINSICSIZE) {
      // We are intrinsically sized -- we should shrinkwrap the outer wrapper's
      // height:
      contentBoxHeight = wrappersMarginBoxHeight;

      // Make sure we obey min/max-height in the case when we're doing intrinsic
      // sizing (we get it for free when we have a non-intrinsic
      // aReflowState.ComputedHeight()).  Note that we do this before
      // adjusting for borderpadding, since mComputedMaxHeight and
      // mComputedMinHeight are content heights.
      contentBoxHeight =
        NS_CSS_MINMAX(contentBoxHeight,
                      aReflowState.ComputedMinHeight(),
                      aReflowState.ComputedMaxHeight());
    }

    // Center child vertically
    nscoord extraSpace = contentBoxHeight - wrappersMarginBoxHeight;
    yoffset += std::max(0, extraSpace / 2);

    // Place the child
    FinishReflowChild(outerWrapperFrame, aPresContext, wrappersDesiredSize,
                      &wrapperReflowState, xoffset, yoffset, 0);

    aDesiredSize.SetBlockStartAscent(
       wrappersDesiredSize.BlockStartAscent() +
       outerWrapperFrame->BStart(aReflowState.GetWritingMode(),
                                 contentBoxWidth));
  }

  aDesiredSize.Width() = contentBoxWidth +
                         aReflowState.ComputedPhysicalBorderPadding().LeftRight();
  aDesiredSize.Height() = contentBoxHeight +
                          aReflowState.ComputedPhysicalBorderPadding().TopBottom();

  aDesiredSize.SetOverflowAreasToDesiredBounds();

  if (outerWrapperFrame) {
    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, outerWrapperFrame);
//.........这里部分代码省略.........

void
nsVideoFrame::Reflow(nsPresContext*           aPresContext,
                     nsHTMLReflowMetrics&     aMetrics,
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsVideoFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aStatus);
  NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
                  ("enter nsVideoFrame::Reflow: availSize=%d,%d",
                  aReflowState.AvailableWidth(), aReflowState.AvailableHeight()));

  NS_PRECONDITION(mState & NS_FRAME_IN_REFLOW, "frame is not in reflow");

  aStatus = NS_FRAME_COMPLETE;

  aMetrics.Width() = aReflowState.ComputedWidth();
  aMetrics.Height() = aReflowState.ComputedHeight();

  // stash this away so we can compute our inner area later
  mBorderPadding   = aReflowState.ComputedPhysicalBorderPadding();

  aMetrics.Width() += mBorderPadding.left + mBorderPadding.right;
  aMetrics.Height() += mBorderPadding.top + mBorderPadding.bottom;

  // Reflow the child frames. We may have up to two, an image frame
  // which is the poster, and a box frame, which is the video controls.
  for (nsIFrame* child : mFrames) {
    if (child->GetContent() == mPosterImage) {
      // Reflow the poster frame.
      nsImageFrame* imageFrame = static_cast<nsImageFrame*>(child);
      nsHTMLReflowMetrics kidDesiredSize(aReflowState);
      WritingMode wm = imageFrame->GetWritingMode();
      LogicalSize availableSize = aReflowState.AvailableSize(wm);
      LogicalSize cbSize = aMetrics.Size(aMetrics.GetWritingMode()).
                             ConvertTo(wm, aMetrics.GetWritingMode());
      nsHTMLReflowState kidReflowState(aPresContext,
                                       aReflowState,
                                       imageFrame,
                                       availableSize,
                                       &cbSize);

      nsRect posterRenderRect;
      if (ShouldDisplayPoster()) {
        posterRenderRect =
          nsRect(nsPoint(mBorderPadding.left, mBorderPadding.top),
                 nsSize(aReflowState.ComputedWidth(),
                        aReflowState.ComputedHeight()));
      }
      kidReflowState.SetComputedWidth(posterRenderRect.width);
      kidReflowState.SetComputedHeight(posterRenderRect.height);
      ReflowChild(imageFrame, aPresContext, kidDesiredSize, kidReflowState,
                  posterRenderRect.x, posterRenderRect.y, 0, aStatus);
      FinishReflowChild(imageFrame, aPresContext,
                        kidDesiredSize, &kidReflowState,
                        posterRenderRect.x, posterRenderRect.y, 0);
    } else if (child->GetContent() == mVideoControls) {
      // Reflow the video controls frame.
      nsBoxLayoutState boxState(PresContext(), aReflowState.rendContext);
      nsSize size = child->GetSize();
      nsBoxFrame::LayoutChildAt(boxState,
                                child,
                                nsRect(mBorderPadding.left,
                                       mBorderPadding.top,
                                       aReflowState.ComputedWidth(),
                                       aReflowState.ComputedHeight()));
      if (child->GetSize() != size) {
        RefPtr<nsRunnable> event = new DispatchResizeToControls(child->GetContent());
        nsContentUtils::AddScriptRunner(event);
      }
    } else if (child->GetContent() == mCaptionDiv) {
      // Reflow to caption div
      nsHTMLReflowMetrics kidDesiredSize(aReflowState);
      WritingMode wm = child->GetWritingMode();
      LogicalSize availableSize = aReflowState.AvailableSize(wm);
      LogicalSize cbSize = aMetrics.Size(aMetrics.GetWritingMode()).
                             ConvertTo(wm, aMetrics.GetWritingMode());
      nsHTMLReflowState kidReflowState(aPresContext,
                                       aReflowState,
                                       child,
                                       availableSize,
                                       &cbSize);
      nsSize size(aReflowState.ComputedWidth(), aReflowState.ComputedHeight());
      size.width -= kidReflowState.ComputedPhysicalBorderPadding().LeftRight();
      size.height -= kidReflowState.ComputedPhysicalBorderPadding().TopBottom();

      kidReflowState.SetComputedWidth(std::max(size.width, 0));
      kidReflowState.SetComputedHeight(std::max(size.height, 0));

      ReflowChild(child, aPresContext, kidDesiredSize, kidReflowState,
                  mBorderPadding.left, mBorderPadding.top, 0, aStatus);
      FinishReflowChild(child, aPresContext,
                        kidDesiredSize, &kidReflowState,
                        mBorderPadding.left, mBorderPadding.top, 0);
    }
  }
  aMetrics.SetOverflowAreasToDesiredBounds();

  FinishAndStoreOverflow(&aMetrics);
//.........这里部分代码省略.........

void
nsRangeFrame::ReflowAnonymousContent(nsPresContext*           aPresContext,
                                     nsHTMLReflowMetrics&     aDesiredSize,
                                     const nsHTMLReflowState& aReflowState)
{
  // The width/height of our content box, which is the available width/height
  // for our anonymous content:
  nscoord rangeFrameContentBoxWidth = aReflowState.ComputedWidth();
  nscoord rangeFrameContentBoxHeight = aReflowState.ComputedHeight();
  if (rangeFrameContentBoxHeight == NS_AUTOHEIGHT) {
    rangeFrameContentBoxHeight = 0;
  }

  nsIFrame* trackFrame = mTrackDiv->GetPrimaryFrame();

  if (trackFrame) { // display:none?

    // Position the track:
    // The idea here is that we allow content authors to style the width,
    // height, border and padding of the track, but we ignore margin and
    // positioning properties and do the positioning ourself to keep the center
    // of the track's border box on the center of the nsRangeFrame's content
    // box.

    nsHTMLReflowState trackReflowState(aPresContext, aReflowState, trackFrame,
                                       nsSize(aReflowState.ComputedWidth(),
                                              NS_UNCONSTRAINEDSIZE));

    // Find the x/y position of the track frame such that it will be positioned
    // as described above. These coordinates are with respect to the
    // nsRangeFrame's border-box.
    nscoord trackX = rangeFrameContentBoxWidth / 2;
    nscoord trackY = rangeFrameContentBoxHeight / 2;

    // Account for the track's border and padding (we ignore its margin):
    trackX -= trackReflowState.ComputedPhysicalBorderPadding().left +
                trackReflowState.ComputedWidth() / 2;
    trackY -= trackReflowState.ComputedPhysicalBorderPadding().top +
                trackReflowState.ComputedHeight() / 2;

    // Make relative to our border box instead of our content box:
    trackX += aReflowState.ComputedPhysicalBorderPadding().left;
    trackY += aReflowState.ComputedPhysicalBorderPadding().top;

    nsReflowStatus frameStatus;
    nsHTMLReflowMetrics trackDesiredSize(aReflowState);
    ReflowChild(trackFrame, aPresContext, trackDesiredSize,
                trackReflowState, trackX, trackY, 0, frameStatus);
    MOZ_ASSERT(NS_FRAME_IS_FULLY_COMPLETE(frameStatus),
               "We gave our child unconstrained height, so it should be complete");
    FinishReflowChild(trackFrame, aPresContext, trackDesiredSize,
                      &trackReflowState, trackX, trackY, 0);
  }

  nsIFrame* thumbFrame = mThumbDiv->GetPrimaryFrame();

  if (thumbFrame) { // display:none?
    nsHTMLReflowState thumbReflowState(aPresContext, aReflowState, thumbFrame,
                                       nsSize(aReflowState.ComputedWidth(),
                                              NS_UNCONSTRAINEDSIZE));

    // Where we position the thumb depends on its size, so we first reflow
    // the thumb at {0,0} to obtain its size, then position it afterwards.

    nsReflowStatus frameStatus;
    nsHTMLReflowMetrics thumbDesiredSize(aReflowState);
    ReflowChild(thumbFrame, aPresContext, thumbDesiredSize,
                thumbReflowState, 0, 0, 0, frameStatus);
    MOZ_ASSERT(NS_FRAME_IS_FULLY_COMPLETE(frameStatus),
               "We gave our child unconstrained height, so it should be complete");
    FinishReflowChild(thumbFrame, aPresContext, thumbDesiredSize,
                      &thumbReflowState, 0, 0, 0);
    DoUpdateThumbPosition(thumbFrame, nsSize(aDesiredSize.Width(),
                                             aDesiredSize.Height()));
  }

  nsIFrame* rangeProgressFrame = mProgressDiv->GetPrimaryFrame();

  if (rangeProgressFrame) { // display:none?
    nsHTMLReflowState progressReflowState(aPresContext, aReflowState,
                                          rangeProgressFrame,
                                          nsSize(aReflowState.ComputedWidth(),
                                                 NS_UNCONSTRAINEDSIZE));

    // We first reflow the range-progress frame at {0,0} to obtain its
    // unadjusted dimensions, then we adjust it to so that the appropriate edge
    // ends at the thumb.

    nsReflowStatus frameStatus;
    nsHTMLReflowMetrics progressDesiredSize(aReflowState);
    ReflowChild(rangeProgressFrame, aPresContext,
                progressDesiredSize, progressReflowState, 0, 0,
                0, frameStatus);
    MOZ_ASSERT(NS_FRAME_IS_FULLY_COMPLETE(frameStatus),
               "We gave our child unconstrained height, so it should be complete");
    FinishReflowChild(rangeProgressFrame, aPresContext,
                      progressDesiredSize, &progressReflowState, 0, 0, 0);
    DoUpdateRangeProgressFrame(rangeProgressFrame, nsSize(aDesiredSize.Width(),
                                                          aDesiredSize.Height()));
  }
//.........这里部分代码省略.........