/* -*- 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): * * 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 ***** */ // YY need to pass isMultiple before create called //#include "nsFormControlFrame.h" #include "nsContainerFrame.h" #include "nsLegendFrame.h" #include "nsIDOMNode.h" #include "nsIDOMHTMLFieldSetElement.h" #include "nsIDOMHTMLLegendElement.h" #include "nsCSSRendering.h" //#include "nsIDOMHTMLCollection.h" #include "nsIContent.h" #include "nsIFrame.h" #include "nsISupports.h" #include "nsIAtom.h" #include "nsPresContext.h" #include "nsFrameManager.h" #include "nsHTMLParts.h" #include "nsGkAtoms.h" #include "nsStyleConsts.h" #include "nsFont.h" #include "nsCOMPtr.h" #ifdef ACCESSIBILITY #include "nsAccessibilityService.h" #endif #include "nsIServiceManager.h" #include "nsDisplayList.h" #include "nsRenderingContext.h" using namespace mozilla; using namespace mozilla::layout; class nsLegendFrame; class nsFieldSetFrame : public nsContainerFrame { public: NS_DECL_FRAMEARENA_HELPERS nsFieldSetFrame(nsStyleContext* aContext); NS_IMETHOD SetInitialChildList(ChildListID aListID, nsFrameList& aChildList); NS_HIDDEN_(nscoord) GetIntrinsicWidth(nsRenderingContext* aRenderingContext, nsLayoutUtils::IntrinsicWidthType); virtual nscoord GetMinWidth(nsRenderingContext* aRenderingContext); virtual nscoord GetPrefWidth(nsRenderingContext* aRenderingContext); virtual nsSize ComputeSize(nsRenderingContext *aRenderingContext, nsSize aCBSize, nscoord aAvailableWidth, nsSize aMargin, nsSize aBorder, nsSize aPadding, PRUint32 aFlags) MOZ_OVERRIDE; virtual nscoord GetBaseline() const; virtual void DestroyFrom(nsIFrame* aDestructRoot); NS_IMETHOD Reflow(nsPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus); NS_IMETHOD BuildDisplayList(nsDisplayListBuilder* aBuilder, const nsRect& aDirtyRect, const nsDisplayListSet& aLists); void PaintBorderBackground(nsRenderingContext& aRenderingContext, nsPoint aPt, const nsRect& aDirtyRect, PRUint32 aBGFlags); NS_IMETHOD AppendFrames(ChildListID aListID, nsFrameList& aFrameList); NS_IMETHOD InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame, nsFrameList& aFrameList); NS_IMETHOD RemoveFrame(ChildListID aListID, nsIFrame* aOldFrame); virtual nsIAtom* GetType() const; #ifdef ACCESSIBILITY virtual already_AddRefed CreateAccessible(); #endif #ifdef DEBUG NS_IMETHOD GetFrameName(nsAString& aResult) const { return MakeFrameName(NS_LITERAL_STRING("FieldSet"), aResult); } #endif protected: virtual PRIntn GetSkipSides() const; void ReparentFrameList(const nsFrameList& aFrameList); // mLegendFrame is a nsLegendFrame or a nsHTMLScrollFrame with the // nsLegendFrame as the scrolled frame (aka content insertion frame). nsIFrame* mLegendFrame; nsIFrame* mContentFrame; nsRect mLegendRect; nscoord mLegendSpace; }; nsIFrame* NS_NewFieldSetFrame(nsIPresShell* aPresShell, nsStyleContext* aContext) { return new (aPresShell) nsFieldSetFrame(aContext); } NS_IMPL_FRAMEARENA_HELPERS(nsFieldSetFrame) nsFieldSetFrame::nsFieldSetFrame(nsStyleContext* aContext) : nsContainerFrame(aContext) { mContentFrame = nsnull; mLegendFrame = nsnull; mLegendSpace = 0; } void nsFieldSetFrame::DestroyFrom(nsIFrame* aDestructRoot) { DestroyAbsoluteFrames(aDestructRoot); nsContainerFrame::DestroyFrom(aDestructRoot); } nsIAtom* nsFieldSetFrame::GetType() const { return nsGkAtoms::fieldSetFrame; } NS_IMETHODIMP nsFieldSetFrame::SetInitialChildList(ChildListID aListID, nsFrameList& aChildList) { // Get the content and legend frames. if (!aChildList.OnlyChild()) { NS_ASSERTION(aChildList.GetLength() == 2, "Unexpected child list"); mContentFrame = aChildList.LastChild(); mLegendFrame = aChildList.FirstChild(); } else { mContentFrame = aChildList.FirstChild(); mLegendFrame = nsnull; } // Queue up the frames for the content frame return nsContainerFrame::SetInitialChildList(kPrincipalList, aChildList); } class nsDisplayFieldSetBorderBackground : public nsDisplayItem { public: nsDisplayFieldSetBorderBackground(nsDisplayListBuilder* aBuilder, nsFieldSetFrame* aFrame) : nsDisplayItem(aBuilder, aFrame) { MOZ_COUNT_CTOR(nsDisplayFieldSetBorderBackground); } #ifdef NS_BUILD_REFCNT_LOGGING virtual ~nsDisplayFieldSetBorderBackground() { MOZ_COUNT_DTOR(nsDisplayFieldSetBorderBackground); } #endif virtual void HitTest(nsDisplayListBuilder* aBuilder, const nsRect& aRect, HitTestState* aState, nsTArray *aOutFrames); virtual void Paint(nsDisplayListBuilder* aBuilder, nsRenderingContext* aCtx); NS_DISPLAY_DECL_NAME("FieldSetBorderBackground", TYPE_FIELDSET_BORDER_BACKGROUND) }; void nsDisplayFieldSetBorderBackground::HitTest(nsDisplayListBuilder* aBuilder, const nsRect& aRect, HitTestState* aState, nsTArray *aOutFrames) { // aPt is guaranteed to be in this item's bounds. We do the hit test based on the // frame bounds even though our background doesn't cover the whole frame. // It's not clear whether this is correct. aOutFrames->AppendElement(mFrame); } void nsDisplayFieldSetBorderBackground::Paint(nsDisplayListBuilder* aBuilder, nsRenderingContext* aCtx) { static_cast(mFrame)-> PaintBorderBackground(*aCtx, ToReferenceFrame(), mVisibleRect, aBuilder->GetBackgroundPaintFlags()); } NS_IMETHODIMP nsFieldSetFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder, const nsRect& aDirtyRect, const nsDisplayListSet& aLists) { // Paint our background and border in a special way. // REVIEW: We don't really need to check frame emptiness here; if it's empty, // the background/border display item won't do anything, and if it isn't empty, // we need to paint the outline if (IsVisibleForPainting(aBuilder)) { if (GetStyleBorder()->mBoxShadow) { nsresult rv = aLists.BorderBackground()->AppendNewToTop(new (aBuilder) nsDisplayBoxShadowOuter(aBuilder, this)); NS_ENSURE_SUCCESS(rv, rv); } // don't bother checking to see if we really have a border or background. // we usually will have a border. nsresult rv = aLists.BorderBackground()->AppendNewToTop(new (aBuilder) nsDisplayFieldSetBorderBackground(aBuilder, this)); NS_ENSURE_SUCCESS(rv, rv); rv = DisplayOutlineUnconditional(aBuilder, aLists); NS_ENSURE_SUCCESS(rv, rv); DO_GLOBAL_REFLOW_COUNT_DSP("nsFieldSetFrame"); } nsDisplayListCollection contentDisplayItems; if (mContentFrame) { // Collect mContentFrame's display items into their own collection. We need // to be calling BuildDisplayList on mContentFrame before mLegendFrame in // case it contains out-of-flow frames whose placeholders are under // mLegendFrame. However, we want mContentFrame's display items to be // after mLegendFrame's display items in z-order, so we need to save them // and append them later. nsresult rv = BuildDisplayListForChild(aBuilder, mContentFrame, aDirtyRect, contentDisplayItems); NS_ENSURE_SUCCESS(rv, rv); } if (mLegendFrame) { // The legend's background goes on our BlockBorderBackgrounds list because // it's a block child. nsDisplayListSet set(aLists, aLists.BlockBorderBackgrounds()); nsresult rv = BuildDisplayListForChild(aBuilder, mLegendFrame, aDirtyRect, set); NS_ENSURE_SUCCESS(rv, rv); } // Put mContentFrame's display items on the master list. Note that // this moves mContentFrame's border/background display items to our // BorderBackground() list, which isn't really correct, but it's OK because // mContentFrame is anonymous and can't have its own border and background. contentDisplayItems.MoveTo(aLists); return NS_OK; } void nsFieldSetFrame::PaintBorderBackground(nsRenderingContext& aRenderingContext, nsPoint aPt, const nsRect& aDirtyRect, PRUint32 aBGFlags) { PRIntn skipSides = GetSkipSides(); const nsStyleBorder* borderStyle = GetStyleBorder(); nscoord topBorder = borderStyle->GetActualBorderWidth(NS_SIDE_TOP); nscoord yoff = 0; nsPresContext* presContext = PresContext(); // if the border is smaller than the legend. Move the border down // to be centered on the legend. // FIXME: This means border-radius clamping is incorrect; we should // override nsIFrame::GetBorderRadii. if (topBorder < mLegendRect.height) yoff = (mLegendRect.height - topBorder)/2; nsRect rect(aPt.x, aPt.y + yoff, mRect.width, mRect.height - yoff); nsCSSRendering::PaintBackground(presContext, aRenderingContext, this, aDirtyRect, rect, aBGFlags); nsCSSRendering::PaintBoxShadowInner(presContext, aRenderingContext, this, rect, aDirtyRect); if (mLegendFrame) { // Use the rect of the legend frame, not mLegendRect, so we draw our // border under the legend's left and right margins. nsRect legendRect = mLegendFrame->GetRect() + aPt; // we should probably use PaintBorderEdges to do this but for now just use clipping // to achieve the same effect. // draw left side nsRect clipRect(rect); clipRect.width = legendRect.x - rect.x; clipRect.height = topBorder; aRenderingContext.PushState(); aRenderingContext.IntersectClip(clipRect); nsCSSRendering::PaintBorder(presContext, aRenderingContext, this, aDirtyRect, rect, mStyleContext, skipSides); aRenderingContext.PopState(); // draw right side clipRect = rect; clipRect.x = legendRect.XMost(); clipRect.width = rect.XMost() - legendRect.XMost(); clipRect.height = topBorder; aRenderingContext.PushState(); aRenderingContext.IntersectClip(clipRect); nsCSSRendering::PaintBorder(presContext, aRenderingContext, this, aDirtyRect, rect, mStyleContext, skipSides); aRenderingContext.PopState(); // draw bottom clipRect = rect; clipRect.y += topBorder; clipRect.height = mRect.height - (yoff + topBorder); aRenderingContext.PushState(); aRenderingContext.IntersectClip(clipRect); nsCSSRendering::PaintBorder(presContext, aRenderingContext, this, aDirtyRect, rect, mStyleContext, skipSides); aRenderingContext.PopState(); } else { nsCSSRendering::PaintBorder(presContext, aRenderingContext, this, aDirtyRect, nsRect(aPt, mRect.Size()), mStyleContext, skipSides); } } nscoord nsFieldSetFrame::GetIntrinsicWidth(nsRenderingContext* aRenderingContext, nsLayoutUtils::IntrinsicWidthType aType) { nscoord legendWidth = 0; nscoord contentWidth = 0; if (mLegendFrame) { legendWidth = nsLayoutUtils::IntrinsicForContainer(aRenderingContext, mLegendFrame, aType); } if (mContentFrame) { contentWidth = nsLayoutUtils::IntrinsicForContainer(aRenderingContext, mContentFrame, aType); } return NS_MAX(legendWidth, contentWidth); } nscoord nsFieldSetFrame::GetMinWidth(nsRenderingContext* aRenderingContext) { nscoord result = 0; DISPLAY_MIN_WIDTH(this, result); result = GetIntrinsicWidth(aRenderingContext, nsLayoutUtils::MIN_WIDTH); return result; } nscoord nsFieldSetFrame::GetPrefWidth(nsRenderingContext* aRenderingContext) { nscoord result = 0; DISPLAY_PREF_WIDTH(this, result); result = GetIntrinsicWidth(aRenderingContext, nsLayoutUtils::PREF_WIDTH); return result; } /* virtual */ nsSize nsFieldSetFrame::ComputeSize(nsRenderingContext *aRenderingContext, nsSize aCBSize, nscoord aAvailableWidth, nsSize aMargin, nsSize aBorder, nsSize aPadding, PRUint32 aFlags) { nsSize result = nsContainerFrame::ComputeSize(aRenderingContext, aCBSize, aAvailableWidth, aMargin, aBorder, aPadding, aFlags); // Fieldsets never shrink below their min width. // If we're a container for font size inflation, then shrink // wrapping inside of us should not apply font size inflation. AutoMaybeNullInflationContainer an(this); nscoord minWidth = GetMinWidth(aRenderingContext); if (minWidth > result.width) result.width = minWidth; return result; } NS_IMETHODIMP nsFieldSetFrame::Reflow(nsPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus) { DO_GLOBAL_REFLOW_COUNT("nsFieldSetFrame"); DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus); NS_PRECONDITION(aReflowState.ComputedWidth() != NS_INTRINSICSIZE, "Should have a precomputed width!"); // Initialize OUT parameter aStatus = NS_FRAME_COMPLETE; //------------ Handle Incremental Reflow ----------------- bool reflowContent; bool reflowLegend; if (aReflowState.ShouldReflowAllKids()) { reflowContent = mContentFrame != nsnull; reflowLegend = mLegendFrame != nsnull; } else { reflowContent = mContentFrame && NS_SUBTREE_DIRTY(mContentFrame); reflowLegend = mLegendFrame && NS_SUBTREE_DIRTY(mLegendFrame); } // We don't allow fieldsets to break vertically. If we did, we'd // need logic here to push and pull overflow frames. nsSize availSize(aReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE); NS_ASSERTION(!mContentFrame || nsLayoutUtils::IntrinsicForContainer(aReflowState.rendContext, mContentFrame, nsLayoutUtils::MIN_WIDTH) <= availSize.width, "Bogus availSize.width; should be bigger"); NS_ASSERTION(!mLegendFrame || nsLayoutUtils::IntrinsicForContainer(aReflowState.rendContext, mLegendFrame, nsLayoutUtils::MIN_WIDTH) <= availSize.width, "Bogus availSize.width; should be bigger"); // get our border and padding const nsMargin &borderPadding = aReflowState.mComputedBorderPadding; nsMargin border = borderPadding - aReflowState.mComputedPadding; // Figure out how big the legend is if there is one. // get the legend's margin nsMargin legendMargin(0,0,0,0); // reflow the legend only if needed if (reflowLegend) { nsHTMLReflowState legendReflowState(aPresContext, aReflowState, mLegendFrame, availSize); nsHTMLReflowMetrics legendDesiredSize; ReflowChild(mLegendFrame, aPresContext, legendDesiredSize, legendReflowState, 0, 0, NS_FRAME_NO_MOVE_FRAME, aStatus); #ifdef NOISY_REFLOW printf(" returned (%d, %d)\n", legendDesiredSize.width, legendDesiredSize.height); #endif // figure out the legend's rectangle legendMargin = mLegendFrame->GetUsedMargin(); mLegendRect.width = legendDesiredSize.width + legendMargin.left + legendMargin.right; mLegendRect.height = legendDesiredSize.height + legendMargin.top + legendMargin.bottom; mLegendRect.x = borderPadding.left; mLegendRect.y = 0; nscoord oldSpace = mLegendSpace; mLegendSpace = 0; if (mLegendRect.height > border.top) { // center the border on the legend mLegendSpace = mLegendRect.height - border.top; } else { mLegendRect.y = (border.top - mLegendRect.height)/2; } // if the legend space changes then we need to reflow the // content area as well. if (mLegendSpace != oldSpace && mContentFrame) { reflowContent = true; } FinishReflowChild(mLegendFrame, aPresContext, &legendReflowState, legendDesiredSize, 0, 0, NS_FRAME_NO_MOVE_FRAME); } else if (!mLegendFrame) { mLegendRect.SetEmpty(); mLegendSpace = 0; } else { // mLegendSpace and mLegendRect haven't changed, but we need // the used margin when placing the legend. legendMargin = mLegendFrame->GetUsedMargin(); } // reflow the content frame only if needed if (reflowContent) { nsHTMLReflowState kidReflowState(aPresContext, aReflowState, mContentFrame, availSize); // Our child is "height:100%" but we actually want its height to be reduced // by the amount of content-height the legend is eating up, unless our // height is unconstrained (in which case the child's will be too). if (aReflowState.ComputedHeight() != NS_UNCONSTRAINEDSIZE) { kidReflowState.SetComputedHeight(NS_MAX(0, aReflowState.ComputedHeight() - mLegendSpace)); } kidReflowState.mComputedMinHeight = NS_MAX(0, aReflowState.mComputedMinHeight - mLegendSpace); if (aReflowState.mComputedMaxHeight != NS_UNCONSTRAINEDSIZE) { kidReflowState.mComputedMaxHeight = NS_MAX(0, aReflowState.mComputedMaxHeight - mLegendSpace); } nsHTMLReflowMetrics kidDesiredSize(aDesiredSize.mFlags); // Reflow the frame NS_ASSERTION(kidReflowState.mComputedMargin == nsMargin(0,0,0,0), "Margins on anonymous fieldset child not supported!"); nsPoint pt(borderPadding.left, borderPadding.top + mLegendSpace); ReflowChild(mContentFrame, aPresContext, kidDesiredSize, kidReflowState, pt.x, pt.y, 0, aStatus); FinishReflowChild(mContentFrame, aPresContext, &kidReflowState, kidDesiredSize, pt.x, pt.y, 0); NS_FRAME_TRACE_REFLOW_OUT("FieldSet::Reflow", aStatus); } nsRect contentRect(0,0,0,0); if (mContentFrame) { // We don't support margins on mContentFrame, so our "content rect" is just // its rect. contentRect = mContentFrame->GetRect(); } // use the computed width if the inner content does not fill it if (aReflowState.ComputedWidth() > contentRect.width) { contentRect.width = aReflowState.ComputedWidth(); } if (mLegendFrame) { // if the content rect is larger then the legend we can align the legend if (contentRect.width > mLegendRect.width) { PRInt32 align = static_cast (mLegendFrame->GetContentInsertionFrame())->GetAlign(); switch(align) { case NS_STYLE_TEXT_ALIGN_RIGHT: mLegendRect.x = contentRect.width - mLegendRect.width + borderPadding.left; break; case NS_STYLE_TEXT_ALIGN_CENTER: // Note: rounding removed; there doesn't seem to be any need mLegendRect.x = contentRect.width / 2 - mLegendRect.width / 2 + borderPadding.left; break; } } else { // otherwise make place for the legend contentRect.width = mLegendRect.width; } // place the legend nsRect actualLegendRect(mLegendRect); actualLegendRect.Deflate(legendMargin); nsPoint curOrigin = mLegendFrame->GetPosition(); // only if the origin changed if ((curOrigin.x != mLegendRect.x) || (curOrigin.y != mLegendRect.y)) { mLegendFrame->SetPosition(nsPoint(actualLegendRect.x , actualLegendRect.y)); nsContainerFrame::PositionFrameView(mLegendFrame); // We need to recursively process the legend frame's // children since we're moving the frame after Reflow. nsContainerFrame::PositionChildViews(mLegendFrame); } } // Return our size and our result if (aReflowState.ComputedHeight() == NS_INTRINSICSIZE) { aDesiredSize.height = mLegendSpace + borderPadding.TopBottom() + contentRect.height; } else { nscoord min = borderPadding.TopBottom() + mLegendRect.height; aDesiredSize.height = aReflowState.ComputedHeight() + borderPadding.TopBottom(); if (aDesiredSize.height < min) aDesiredSize.height = min; } aDesiredSize.width = contentRect.width + borderPadding.LeftRight(); aDesiredSize.SetOverflowAreasToDesiredBounds(); if (mLegendFrame) ConsiderChildOverflow(aDesiredSize.mOverflowAreas, mLegendFrame); if (mContentFrame) ConsiderChildOverflow(aDesiredSize.mOverflowAreas, mContentFrame); FinishReflowWithAbsoluteFrames(aPresContext, aDesiredSize, aReflowState, aStatus); Invalidate(aDesiredSize.VisualOverflow()); NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize); return NS_OK; } PRIntn nsFieldSetFrame::GetSkipSides() const { return 0; } NS_IMETHODIMP nsFieldSetFrame::AppendFrames(ChildListID aListID, nsFrameList& aFrameList) { // aFrameList is not allowed to contain "the legend" for this fieldset ReparentFrameList(aFrameList); return mContentFrame->AppendFrames(aListID, aFrameList); } NS_IMETHODIMP nsFieldSetFrame::InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame, nsFrameList& aFrameList) { NS_ASSERTION(!aPrevFrame || aPrevFrame->GetParent() == this || aPrevFrame->GetParent() == mContentFrame, "inserting after sibling frame with different parent"); // aFrameList is not allowed to contain "the legend" for this fieldset ReparentFrameList(aFrameList); if (NS_UNLIKELY(aPrevFrame == mLegendFrame)) { aPrevFrame = nsnull; } return mContentFrame->InsertFrames(aListID, aPrevFrame, aFrameList); } NS_IMETHODIMP nsFieldSetFrame::RemoveFrame(ChildListID aListID, nsIFrame* aOldFrame) { // For reference, see bug 70648, bug 276104 and bug 236071. NS_ASSERTION(aOldFrame != mLegendFrame, "Cannot remove mLegendFrame here"); return mContentFrame->RemoveFrame(aListID, aOldFrame); } #ifdef ACCESSIBILITY already_AddRefed nsFieldSetFrame::CreateAccessible() { nsAccessibilityService* accService = nsIPresShell::AccService(); if (accService) { return accService->CreateHTMLGroupboxAccessible(mContent, PresContext()->PresShell()); } return nsnull; } #endif void nsFieldSetFrame::ReparentFrameList(const nsFrameList& aFrameList) { nsFrameManager* frameManager = PresContext()->FrameManager(); for (nsFrameList::Enumerator e(aFrameList); !e.AtEnd(); e.Next()) { NS_ASSERTION(mLegendFrame || e.get()->GetType() != nsGkAtoms::legendFrame, "The fieldset's legend is not allowed in this list"); e.get()->SetParent(mContentFrame); frameManager->ReparentStyleContext(e.get()); } } nscoord nsFieldSetFrame::GetBaseline() const { // We know mContentFrame is a block, so calling GetBaseline() on it will do // the right thing (that being to return the baseline of the last line). NS_ASSERTION(nsLayoutUtils::GetAsBlock(mContentFrame), "Unexpected mContentFrame"); return mContentFrame->GetPosition().y + mContentFrame->GetBaseline(); }