/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ // vim:cindent:ts=2:et:sw=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 Communicator client 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): * David Baron * * 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 ***** */ /* class that a parent frame uses to reflow a block frame */ #include "nsBlockReflowContext.h" #include "nsLineLayout.h" #include "nsSpaceManager.h" #include "nsIFontMetrics.h" #include "nsPresContext.h" #include "nsFrameManager.h" #include "nsIContent.h" #include "nsStyleContext.h" #include "nsHTMLContainerFrame.h" #include "nsBlockFrame.h" #include "nsLineBox.h" #include "nsIDOMHTMLTableCellElement.h" #include "nsIDOMHTMLBodyElement.h" #include "nsGkAtoms.h" #include "nsCOMPtr.h" #include "nsLayoutUtils.h" #ifdef NS_DEBUG #undef NOISY_MAX_ELEMENT_SIZE #undef REALLY_NOISY_MAX_ELEMENT_SIZE #undef NOISY_VERTICAL_MARGINS #else #undef NOISY_MAX_ELEMENT_SIZE #undef REALLY_NOISY_MAX_ELEMENT_SIZE #undef NOISY_VERTICAL_MARGINS #endif nsBlockReflowContext::nsBlockReflowContext(nsPresContext* aPresContext, const nsHTMLReflowState& aParentRS) : mPresContext(aPresContext), mOuterReflowState(aParentRS), mMetrics() { mStyleBorder = nsnull; mStyleMargin = nsnull; mStylePadding = nsnull; } static nsIFrame* DescendIntoBlockLevelFrame(nsIFrame* aFrame) { nsIAtom* type = aFrame->GetType(); if (type == nsGkAtoms::columnSetFrame) return DescendIntoBlockLevelFrame(aFrame->GetFirstChild(nsnull)); return aFrame; } PRBool nsBlockReflowContext::ComputeCollapsedTopMargin(const nsHTMLReflowState& aRS, nsCollapsingMargin* aMargin, nsIFrame* aClearanceFrame, PRBool* aMayNeedRetry, PRBool* aBlockIsEmpty) { // Include frame's top margin aMargin->Include(aRS.mComputedMargin.top); // The inclusion of the bottom margin when empty is done by the caller // since it doesn't need to be done by the top-level (non-recursive) // caller. #ifdef NOISY_VERTICAL_MARGINS nsFrame::ListTag(stdout, aRS.frame); printf(": %d => %d\n", aRS.mComputedMargin.top, aMargin->get()); #endif PRBool dirtiedLine = PR_FALSE; PRBool setBlockIsEmpty = PR_FALSE; // Calculate the frame's generational top-margin from its child // blocks. Note that if the frame has a non-zero top-border or // top-padding then this step is skipped because it will be a margin // root. It is also skipped if the frame is a margin root for other // reasons. void* bf; nsIFrame* frame = DescendIntoBlockLevelFrame(aRS.frame); nsPresContext* prescontext = frame->PresContext(); if (0 == aRS.mComputedBorderPadding.top && NS_SUCCEEDED(frame->QueryInterface(kBlockFrameCID, &bf)) && !nsBlockFrame::BlockIsMarginRoot(frame)) { // iterate not just through the lines of 'block' but also its // overflow lines and the normal and overflow lines of its next in // flows. Note that this will traverse some frames more than once: // for example, if A contains B and A->nextinflow contains // B->nextinflow, we'll traverse B->nextinflow twice. But this is // OK because our traversal is idempotent. for (nsBlockFrame* block = NS_STATIC_CAST(nsBlockFrame*, frame); block; block = NS_STATIC_CAST(nsBlockFrame*, block->GetNextInFlow())) { for (PRBool overflowLines = PR_FALSE; overflowLines <= PR_TRUE; ++overflowLines) { nsBlockFrame::line_iterator line; nsBlockFrame::line_iterator line_end; PRBool anyLines = PR_TRUE; if (overflowLines) { nsLineList* lines = block->GetOverflowLines(); if (!lines) { anyLines = PR_FALSE; } else { line = lines->begin(); line_end = lines->end(); } } else { line = block->begin_lines(); line_end = block->end_lines(); } for (; anyLines && line != line_end; ++line) { if (!aClearanceFrame && line->HasClearance()) { // If we don't have a clearance frame, then we're computing // the collapsed margin in the first pass, assuming that all // lines have no clearance. So clear their clearance flags. line->ClearHasClearance(); line->MarkDirty(); dirtiedLine = PR_TRUE; } PRBool isEmpty; if (line->IsInline()) { isEmpty = line->IsEmpty(); } else { nsIFrame* kid = line->mFirstChild; if (kid == aClearanceFrame) { line->SetHasClearance(); line->MarkDirty(); dirtiedLine = PR_TRUE; goto done; } // Here is where we recur. Now that we have determined that a // generational collapse is required we need to compute the // child blocks margin and so in so that we can look into // it. For its margins to be computed we need to have a reflow // state for it. // We may have to construct an extra reflow state here if // we drilled down through a block wrapper. At the moment // we can only drill down one level so we only have to support // one extra reflow state. const nsHTMLReflowState* outerReflowState = &aRS; if (frame != aRS.frame) { NS_ASSERTION(frame->GetParent() == aRS.frame, "Can only drill through one level of block wrapper"); nsSize availSpace(aRS.ComputedWidth(), aRS.mComputedHeight); outerReflowState = new nsHTMLReflowState(prescontext, aRS, frame, availSpace); if (!outerReflowState) goto done; } { nsSize availSpace(outerReflowState->ComputedWidth(), outerReflowState->mComputedHeight); nsHTMLReflowState innerReflowState(prescontext, *outerReflowState, kid, availSpace); // Record that we're being optimistic by assuming the kid // has no clearance if (kid->GetStyleDisplay()->mBreakType != NS_STYLE_CLEAR_NONE) { *aMayNeedRetry = PR_TRUE; } if (ComputeCollapsedTopMargin(innerReflowState, aMargin, aClearanceFrame, aMayNeedRetry, &isEmpty)) { line->MarkDirty(); dirtiedLine = PR_TRUE; } if (isEmpty) aMargin->Include(innerReflowState.mComputedMargin.bottom); } if (outerReflowState != &aRS) { delete NS_CONST_CAST(nsHTMLReflowState*, outerReflowState); } } if (!isEmpty) { if (!setBlockIsEmpty && aBlockIsEmpty) { setBlockIsEmpty = PR_TRUE; *aBlockIsEmpty = PR_FALSE; } goto done; } } if (!setBlockIsEmpty && aBlockIsEmpty) { // The first time we reach here is when this is the first block // and we have processed all its normal lines. setBlockIsEmpty = PR_TRUE; // All lines are empty, or we wouldn't be here! *aBlockIsEmpty = aRS.frame->IsSelfEmpty(); } } } done: ; } if (!setBlockIsEmpty && aBlockIsEmpty) { *aBlockIsEmpty = aRS.frame->IsEmpty(); } #ifdef NOISY_VERTICAL_MARGINS nsFrame::ListTag(stdout, aRS.frame); printf(": => %d\n", aMargin->get()); #endif return dirtiedLine; } static void nsPointDtor(void *aFrame, nsIAtom *aPropertyName, void *aPropertyValue, void *aDtorData) { nsPoint *point = NS_STATIC_CAST(nsPoint*, aPropertyValue); delete point; } nsresult nsBlockReflowContext::ReflowBlock(const nsRect& aSpace, PRBool aApplyTopMargin, nsCollapsingMargin& aPrevMargin, nscoord aClearance, PRBool aIsAdjacentWithTop, nsMargin& aComputedOffsets, nsHTMLReflowState& aFrameRS, nsReflowStatus& aFrameReflowStatus) { nsresult rv = NS_OK; mFrame = aFrameRS.frame; mSpace = aSpace; const nsStyleDisplay* display = mFrame->GetStyleDisplay(); aComputedOffsets = aFrameRS.mComputedOffsets; if (NS_STYLE_POSITION_RELATIVE == display->mPosition) { nsPropertyTable *propTable = mPresContext->PropertyTable(); nsPoint *offsets = NS_STATIC_CAST(nsPoint*, propTable->GetProperty(mFrame, nsGkAtoms::computedOffsetProperty)); if (offsets) offsets->MoveTo(aComputedOffsets.left, aComputedOffsets.top); else { offsets = new nsPoint(aComputedOffsets.left, aComputedOffsets.top); if (offsets) propTable->SetProperty(mFrame, nsGkAtoms::computedOffsetProperty, offsets, nsPointDtor, nsnull); } } if (!aIsAdjacentWithTop) { aFrameRS.mFlags.mIsTopOfPage = PR_FALSE; // make sure this is cleared } mComputedWidth = aFrameRS.ComputedWidth(); if (aApplyTopMargin) { mTopMargin = aPrevMargin; #ifdef NOISY_VERTICAL_MARGINS nsFrame::ListTag(stdout, mOuterReflowState.frame); printf(": reflowing "); nsFrame::ListTag(stdout, mFrame); printf(" margin => %d, clearance => %d\n", mTopMargin.get(), aClearance); #endif // Adjust the available height if its constrained so that the // child frame doesn't think it can reflow into its margin area. if (NS_UNCONSTRAINEDSIZE != aFrameRS.availableHeight) { aFrameRS.availableHeight -= mTopMargin.get() + aClearance; } } // Compute x/y coordinate where reflow will begin. Use the rules // from 10.3.3 to determine what to apply. At this point in the // reflow auto left/right margins will have a zero value. mMargin = aFrameRS.mComputedMargin; mStyleBorder = aFrameRS.mStyleBorder; mStyleMargin = aFrameRS.mStyleMargin; mStylePadding = aFrameRS.mStylePadding; nscoord x; nscoord y = mSpace.y + mTopMargin.get() + aClearance; // If it's a right floated element, then calculate the x-offset // differently if (NS_STYLE_FLOAT_RIGHT == aFrameRS.mStyleDisplay->mFloats) { nscoord frameWidth; if (NS_UNCONSTRAINEDSIZE == aFrameRS.ComputedWidth()) { // Use the current frame width frameWidth = mFrame->GetSize().width; } else { frameWidth = aFrameRS.ComputedWidth() + aFrameRS.mComputedBorderPadding.left + aFrameRS.mComputedBorderPadding.right; } // if this is an unconstrained width reflow, then just place the float at the left margin if (NS_UNCONSTRAINEDSIZE == mSpace.width) x = mSpace.x; else x = mSpace.XMost() - mMargin.right - frameWidth; } else { x = mSpace.x + mMargin.left; } mX = x; mY = y; // Compute the translation to be used for adjusting the spacemanagager // coordinate system for the frame. The spacemanager coordinates are // inside the callers border+padding, but the x/y coordinates // are not (recall that frame coordinates are relative to the parents // origin and that the parents border/padding is inside the // parent frame. Therefore we have to subtract out the parents // border+padding before translating. nscoord tx = x - mOuterReflowState.mComputedBorderPadding.left; nscoord ty = y - mOuterReflowState.mComputedBorderPadding.top; // If the element is relatively positioned, then adjust x and y accordingly if (NS_STYLE_POSITION_RELATIVE == aFrameRS.mStyleDisplay->mPosition) { x += aFrameRS.mComputedOffsets.left; y += aFrameRS.mComputedOffsets.top; } // Let frame know that we are reflowing it mFrame->WillReflow(mPresContext); // Position it and its view (if it has one) // Note: Use "x" and "y" and not "mX" and "mY" because they more accurately // represents where we think the block will be placed // XXXldb That's fine for view positioning, but not for reflow! mFrame->SetPosition(nsPoint(x, y)); nsContainerFrame::PositionFrameView(mFrame); #ifdef DEBUG mMetrics.width = nscoord(0xdeadbeef); mMetrics.height = nscoord(0xdeadbeef); #endif mOuterReflowState.mSpaceManager->Translate(tx, ty); rv = mFrame->Reflow(mPresContext, mMetrics, aFrameRS, aFrameReflowStatus); mOuterReflowState.mSpaceManager->Translate(-tx, -ty); #ifdef DEBUG if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) { if (CRAZY_WIDTH(mMetrics.width) || CRAZY_HEIGHT(mMetrics.height)) { printf("nsBlockReflowContext: "); nsFrame::ListTag(stdout, mFrame); printf(" metrics=%d,%d!\n", mMetrics.width, mMetrics.height); } if ((mMetrics.width == nscoord(0xdeadbeef)) || (mMetrics.height == nscoord(0xdeadbeef))) { printf("nsBlockReflowContext: "); nsFrame::ListTag(stdout, mFrame); printf(" didn't set w/h %d,%d!\n", mMetrics.width, mMetrics.height); } } #endif if (!(NS_FRAME_OUTSIDE_CHILDREN & mFrame->GetStateBits())) { // Provide overflow area for child that doesn't have any mMetrics.mOverflowArea.x = 0; mMetrics.mOverflowArea.y = 0; mMetrics.mOverflowArea.width = mMetrics.width; mMetrics.mOverflowArea.height = mMetrics.height; } if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus) || (mFrame->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) { // If frame is complete and has a next-in-flow, we need to delete // them now. Do not do this when a break-before is signaled because // the frame is going to get reflowed again (and may end up wanting // a next-in-flow where it ends up), unless it is an out of flow frame. if (NS_FRAME_IS_COMPLETE(aFrameReflowStatus)) { nsIFrame* kidNextInFlow = mFrame->GetNextInFlow(); if (nsnull != kidNextInFlow) { // Remove all of the childs next-in-flows. Make sure that we ask // the right parent to do the removal (it's possible that the // parent is not this because we are executing pullup code). // Floats will eventually be removed via nsBlockFrame::RemoveFloat // which detaches the placeholder from the float. /* XXX promote DeleteChildsNextInFlow to nsIFrame to elminate this cast */ NS_STATIC_CAST(nsHTMLContainerFrame*, kidNextInFlow->GetParent()) ->DeleteNextInFlowChild(mPresContext, kidNextInFlow); } } } return rv; } /** * Attempt to place the block frame within the available space. If * it fits, apply horizontal positioning (CSS 10.3.3), collapse * margins (CSS2 8.3.1). Also apply relative positioning. */ PRBool nsBlockReflowContext::PlaceBlock(const nsHTMLReflowState& aReflowState, PRBool aForceFit, nsLineBox* aLine, const nsMargin& aComputedOffsets, nsCollapsingMargin& aBottomMarginResult, nsRect& aInFlowBounds, nsRect& aCombinedRect, nsReflowStatus aReflowStatus) { // Compute collapsed bottom margin value. if (NS_FRAME_IS_COMPLETE(aReflowStatus)) { aBottomMarginResult = mMetrics.mCarriedOutBottomMargin; aBottomMarginResult.Include(mMargin.bottom); } else { // The used bottom-margin is set to zero above a break. aBottomMarginResult.Zero(); } nscoord x = mX; nscoord y = mY; nscoord backupContainingBlockAdvance = 0; // Check whether the block's bottom margin collapses with its top // margin. See CSS 2.1 section 8.3.1; those rules seem to match // nsBlockFrame::IsEmpty(). Any such block must have zero height so // check that first. Note that a block can have clearance and still // have adjoining top/bottom margins, because the clearance goes // above the top margin. // Mark the frame as non-dirty; it has been reflowed (or we wouldn't // be here), and we don't want to assert in CachedIsEmpty() mFrame->RemoveStateBits(NS_FRAME_IS_DIRTY); PRBool empty = 0 == mMetrics.height && aLine->CachedIsEmpty(); if (empty) { // Collapse the bottom margin with the top margin that was already // applied. aBottomMarginResult.Include(mTopMargin); #ifdef NOISY_VERTICAL_MARGINS printf(" "); nsFrame::ListTag(stdout, mOuterReflowState.frame); printf(": "); nsFrame::ListTag(stdout, mFrame); printf(" -- collapsing top & bottom margin together; y=%d spaceY=%d\n", y, mSpace.y); #endif // Section 8.3.1 of CSS 2.1 says that blocks with adjoining // top/bottom margins whose top margin collapses with their // parent's top margin should have their top border-edge at the // top border-edge of their parent. We actually don't have to do // anything special to make this happen. In that situation, // nsBlockFrame::ShouldApplyTopMargin will have returned PR_FALSE, // and mTopMargin and aClearance will have been zero in // ReflowBlock. // If we did apply our top margin, but now we're collapsing it // into the bottom margin, we need to back up the containing // block's y-advance by our top margin so that it doesn't get // counted twice. Note that here we're allowing the line's bounds // to become different from the block's position; we do this // because the containing block will place the next line at the // line's YMost, and it must place the next line at a different // point from where this empty block will be. backupContainingBlockAdvance = mTopMargin.get(); } // See if the frame fit. If it's the first frame or empty then it // always fits. If the height is unconstrained then it always fits, // even if there's some sort of integer overflow that makes y + // mMetrics.height appear to go beyond the available height. if (!empty && !aForceFit && mSpace.height != NS_UNCONSTRAINEDSIZE) { nscoord yMost = y - backupContainingBlockAdvance + mMetrics.height; if (yMost > mSpace.YMost()) { // didn't fit, we must acquit. mFrame->DidReflow(mPresContext, &aReflowState, NS_FRAME_REFLOW_FINISHED); return PR_FALSE; } } aInFlowBounds = nsRect(x, y - backupContainingBlockAdvance, mMetrics.width, mMetrics.height); // Apply CSS relative positioning const nsStyleDisplay* styleDisp = mFrame->GetStyleDisplay(); if (NS_STYLE_POSITION_RELATIVE == styleDisp->mPosition) { x += aComputedOffsets.left; y += aComputedOffsets.top; } // Now place the frame and complete the reflow process nsContainerFrame::FinishReflowChild(mFrame, mPresContext, &aReflowState, mMetrics, x, y, 0); aCombinedRect = mMetrics.mOverflowArea + nsPoint(x, y); return PR_TRUE; }