gecko-dev/layout/generic/nsBlockReflowContext.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape 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/NPL/
*
* 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 Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
* David Baron <dbaron@fas.harvard.edu>
*/
#include "nsBlockReflowContext.h"
#include "nsLineLayout.h"
#include "nsHTMLIIDs.h"
#include "nsISpaceManager.h"
#include "nsIFontMetrics.h"
#include "nsIPresContext.h"
#include "nsIContent.h"
#include "nsIStyleContext.h"
#include "nsIReflowCommand.h"
#include "nsHTMLContainerFrame.h"
#include "nsBlockFrame.h"
#include "nsIDOMHTMLTableCellElement.h"
#include "nsIDOMHTMLBodyElement.h"
#include "nsLayoutAtoms.h"
#include "nsCOMPtr.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(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentRS,
PRBool aComputeMaxElementSize,
PRBool aComputeMaximumWidth)
: mPresContext(aPresContext),
mOuterReflowState(aParentRS),
mMetrics(aComputeMaxElementSize ? &mMaxElementSize : nsnull),
mMaxElementSize(0, 0),
mIsTable(PR_FALSE),
mComputeMaximumWidth(aComputeMaximumWidth),
mBlockShouldInvalidateItself(PR_FALSE)
{
mStyleBorder = nsnull;
mStyleMargin = nsnull;
mStylePadding = nsnull;
if (mComputeMaximumWidth)
mMetrics.mFlags |= NS_REFLOW_CALC_MAX_WIDTH;
}
nscoord
nsBlockReflowContext::ComputeCollapsedTopMargin(nsIPresContext* aPresContext,
nsHTMLReflowState& aRS)
{
// Get aFrame's top margin
nscoord topMargin = aRS.mComputedMargin.top;
// Calculate aFrame's generational top-margin from its child
// blocks. Note that if aFrame 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.
nscoord generationalTopMargin = 0;
if (0 == aRS.mComputedBorderPadding.top) {
nsFrameState state;
aRS.frame->GetFrameState(&state);
if (!(state & NS_BLOCK_MARGIN_ROOT)) {
nsBlockFrame* bf;
if (NS_SUCCEEDED(aRS.frame->QueryInterface(kBlockFrameCID, (void**)&bf))) {
// Ask the block frame for the top block child that we should
// try to collapse the top margin with.
// XXX If the block is empty, we need to check its bottom margin
// and its sibling's top margin (etc.) too! See XXXldb comment about
// emptyness below in PlaceBlock.
nsIFrame* childFrame = bf->GetTopBlockChild();
if (nsnull != childFrame) {
// Here is where we recurse. 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.
nsSize availSpace(aRS.mComputedWidth, aRS.mComputedHeight);
nsHTMLReflowState reflowState(aPresContext, aRS, childFrame,
availSpace);
generationalTopMargin =
ComputeCollapsedTopMargin(aPresContext, reflowState);
}
}
}
}
// Now compute the collapsed top-margin value. At this point we have
// the child frames effective top margin value.
nscoord collapsedTopMargin = MaxMargin(topMargin, generationalTopMargin);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, aRS.frame);
printf(": topMargin=%d generationalTopMargin=%d => %d\n",
topMargin, generationalTopMargin, collapsedTopMargin);
#endif
return collapsedTopMargin;
}
struct nsBlockHorizontalAlign {
nscoord mXOffset; // left edge
nscoord mLeftMargin;
nscoord mRightMargin;
};
// Given the width of the block frame and a suggested x-offset calculate
// the actual x-offset taking into account horizontal alignment. Also returns
// the actual left and right margin
void
nsBlockReflowContext::AlignBlockHorizontally(nscoord aWidth,
nsBlockHorizontalAlign &aAlign)
{
// Initialize OUT parameters
aAlign.mLeftMargin = mMargin.left;
aAlign.mRightMargin = mMargin.right;
// Get style unit associated with the left and right margins
nsStyleUnit leftUnit = mStyleMargin->mMargin.GetLeftUnit();
if (eStyleUnit_Inherit == leftUnit) {
leftUnit = GetRealMarginLeftUnit();
}
nsStyleUnit rightUnit = mStyleMargin->mMargin.GetRightUnit();
if (eStyleUnit_Inherit == rightUnit) {
rightUnit = GetRealMarginRightUnit();
}
// Apply post-reflow horizontal alignment. When a block element
// doesn't use it all of the available width then we need to
// align it using the text-align property.
if (NS_UNCONSTRAINEDSIZE != mSpace.width) {
// It is possible that the object reflowed was given a
// constrained width and ended up picking a different width
// (e.g. a table width a set width that ended up larger
// because its contents required it). When this happens we
// need to recompute auto margins because the reflow state's
// computations are no longer valid.
if (aWidth != mComputedWidth) {
if (eStyleUnit_Auto == leftUnit) {
aAlign.mXOffset = 0;
aAlign.mLeftMargin = 0;
}
if (eStyleUnit_Auto == rightUnit) {
aAlign.mRightMargin = 0;
}
}
// Compute how much remaining space there is, and in special
// cases apply it (normally we should get zero here because of
// the logic in nsHTMLReflowState).
nscoord remainingSpace = mSpace.XMost() - (aAlign.mXOffset + aWidth +
aAlign.mRightMargin);
if (remainingSpace > 0) {
// The block/table frame didn't use all of the available
// space. Synthesize margins for its horizontal placement.
if (eStyleUnit_Auto == leftUnit) {
if (eStyleUnit_Auto == rightUnit) {
// When both margins are auto, we center the block
aAlign.mXOffset += remainingSpace / 2;
}
else {
// When the left margin is auto we right align the block
aAlign.mXOffset += remainingSpace;
}
}
else if (eStyleUnit_Auto != rightUnit) {
// The block/table doesn't have auto margins.
// For normal (non-table) blocks we don't get here because
// nsHTMLReflowState::CalculateBlockSideMargins handles this.
// (I think there may be an exception to that, though...)
// We use a special value of the text-align property for
// HTML alignment (the CENTER element and DIV ALIGN=...)
// since it acts on blocks and tables rather than just
// being a text-align.
// So, check the text-align value from the parent to see if
// it has one of these special values.
const nsStyleText* styleText = mOuterReflowState.mStyleText;
if (styleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_RIGHT) {
aAlign.mXOffset += remainingSpace;
} else if (styleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER) {
aAlign.mXOffset += remainingSpace / 2;
} else {
// If we don't have a special text-align value indicating
// HTML alignment, then use the CSS rules.
// When neither margin is auto then the block is said to
// be over constrained, Depending on the direction, choose
// which margin to treat as auto.
PRUint8 direction = mOuterReflowState.mStyleVisibility->mDirection;
if (NS_STYLE_DIRECTION_RTL == direction) {
// The left margin becomes auto
aAlign.mXOffset += remainingSpace;
}
//else {
// The right margin becomes auto which is a no-op
//}
}
}
}
}
}
nsresult
nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aFrameReflowStatus)
{
nsresult rv = NS_OK;
mFrame = aFrame;
mSpace = aSpace;
// Get reflow reason set correctly. It's possible that a child was
// created and then it was decided that it could not be reflowed
// (for example, a block frame that isn't at the start of a
// line). In this case the reason will be wrong so we need to check
// the frame state.
nsReflowReason reason = eReflowReason_Resize;
nsFrameState state;
aFrame->GetFrameState(&state);
if (NS_FRAME_FIRST_REFLOW & state) {
reason = eReflowReason_Initial;
}
else if (mNextRCFrame == aFrame) {
reason = eReflowReason_Incremental;
// Make sure we only incrementally reflow once
mNextRCFrame = nsnull;
}
else if (mOuterReflowState.reason == eReflowReason_StyleChange) {
reason = eReflowReason_StyleChange;
}
else if (mOuterReflowState.reason == eReflowReason_Dirty) {
if (state & NS_FRAME_IS_DIRTY)
reason = eReflowReason_Dirty;
}
else {
if (mOuterReflowState.reason == eReflowReason_Incremental) {
// If the incremental reflow command is a StyleChanged reflow
// and it's target is the current block, then make sure we send
// StyleChange reflow reasons down to all the children so that
// they don't over-optimize their reflow.
nsIReflowCommand* rc = mOuterReflowState.reflowCommand;
if (rc) {
nsIReflowCommand::ReflowType type;
rc->GetType(type);
if (type == nsIReflowCommand::StyleChanged) {
nsIFrame* target;
rc->GetTarget(target);
if (target == mOuterReflowState.frame) {
reason = eReflowReason_StyleChange;
}
}
else if (type == nsIReflowCommand::ReflowDirty &&
(state & NS_FRAME_IS_DIRTY)) {
reason = eReflowReason_Dirty;
}
}
/*
if (eReflowReason_Resize == reason) {
// we're doing a resize reflow, even though our outer reflow state is incremental
// text (and possibly other objects) don't do incremental painting for resize reflows
// so, we have to handle the invalidation for repainting ourselves
mBlockShouldInvalidateItself = PR_TRUE;
}
*/
}
}
// Setup reflow state for reflowing the frame
// XXX subtract out vertical margin?
nsSize availSpace(aSpace.width, aSpace.height);
/* We build a different reflow context based on the width attribute of the block,
* if it's a floater.
* Auto-width floaters need to have their containing-block size set explicitly,
* factoring in other floaters that impact it.
* It's possible this should be quirks-only.
* All other blocks proceed normally.
*/
// XXXldb We should really fix this in nsHTMLReflowState::InitConstraints instead.
const nsStylePosition* position;
aFrame->GetStyleData(eStyleStruct_Position,
(const nsStyleStruct*&)position);
nsStyleUnit widthUnit = position->mWidth.GetUnit();
const nsStyleDisplay* display;
aFrame->GetStyleData(eStyleStruct_Display,
(const nsStyleStruct*&)display);
if ((eStyleUnit_Auto == widthUnit) &&
((NS_STYLE_FLOAT_LEFT == display->mFloats) ||
(NS_STYLE_FLOAT_RIGHT == display->mFloats))) {
// Construct the reflow state using the ctor that explicitly
// constrains the containing block's width and height to the
// available width and height.
nsHTMLReflowState autoReflowState(mPresContext, mOuterReflowState, aFrame,
availSpace, aSpace.width, aSpace.height);
autoReflowState.reason = reason;
rv = DoReflowBlock(autoReflowState, reason, aFrame, aSpace,
aApplyTopMargin, aPrevBottomMargin,
aIsAdjacentWithTop,
aComputedOffsets,
aFrameReflowStatus);
}
else {
// Construct the reflow state using the ctor that will use the
// containing block's computed width and height (or handle derive
// appropriate values for an absolutely positioned frame).
nsHTMLReflowState normalReflowState(mPresContext, mOuterReflowState, aFrame,
availSpace, reason);
rv = DoReflowBlock(normalReflowState, reason, aFrame, aSpace,
aApplyTopMargin, aPrevBottomMargin,
aIsAdjacentWithTop,
aComputedOffsets,
aFrameReflowStatus);
}
return rv;
}
static void
ComputeShrinkwrapMargins(const nsStyleMargin* aStyleMargin, nscoord aWidth, nsMargin& aMargin, nscoord& aXToUpdate) {
nscoord boxWidth = aWidth;
float leftPct = 0.0;
float rightPct = 0.0;
if (eStyleUnit_Percent == aStyleMargin->mMargin.GetLeftUnit()) {
nsStyleCoord leftCoord;
aStyleMargin->mMargin.GetLeft(leftCoord);
leftPct = leftCoord.GetPercentValue();
} else {
boxWidth += aMargin.left;
}
if (eStyleUnit_Percent == aStyleMargin->mMargin.GetRightUnit()) {
nsStyleCoord rightCoord;
aStyleMargin->mMargin.GetRight(rightCoord);
rightPct = rightCoord.GetPercentValue();
} else {
boxWidth += aMargin.right;
}
// The total shrink wrap width "sww" is calculated by the expression:
// sww = bw + (mp * sww)
// where "bw" is the box width (frame width plus margins that aren't percentage
// based) and "mp" are the total margin percentages (i.e., the left percentage
// value plus the right percentage value)
// Solving for "sww" gives us:
// sww = bw / (1 - mp)
// Note that this is only well defined for "mp" less than 100%
// XXXldb Um... percentage margins are based on the containing block width.
float marginPct = leftPct + rightPct;
if (marginPct >= 1.0) {
// Ignore the right percentage and just use the left percentage
// XXX Pay attention to direction property...
marginPct = leftPct;
rightPct = 0.0;
}
if ((marginPct > 0.0) && (marginPct < 1.0)) {
double shrinkWrapWidth = float(boxWidth) / (1.0 - marginPct);
if (eStyleUnit_Percent == aStyleMargin->mMargin.GetLeftUnit()) {
aMargin.left = NSToCoordFloor((float)(shrinkWrapWidth * leftPct));
aXToUpdate += aMargin.left;
}
if (eStyleUnit_Percent == aStyleMargin->mMargin.GetRightUnit()) {
aMargin.right = NSToCoordFloor((float)(shrinkWrapWidth * rightPct));
}
}
}
nsresult
nsBlockReflowContext::DoReflowBlock(nsHTMLReflowState &aReflowState,
nsReflowReason aReason,
nsIFrame* aFrame,
const nsRect& aSpace,
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aFrameReflowStatus)
{
nsresult rv = NS_OK;
nsFrameState state;
aFrame->GetFrameState(&state);
aComputedOffsets = aReflowState.mComputedOffsets;
aReflowState.mLineLayout = nsnull;
if (!aIsAdjacentWithTop) {
aReflowState.isTopOfPage = PR_FALSE; // make sure this is cleared
}
mIsTable = NS_STYLE_DISPLAY_TABLE == aReflowState.mStyleDisplay->mDisplay;
mComputedWidth = aReflowState.mComputedWidth;
nscoord topMargin = 0;
if (aApplyTopMargin) {
// Compute the childs collapsed top margin (its margin collpased
// with its first childs top-margin -- recursively).
topMargin = ComputeCollapsedTopMargin(mPresContext, aReflowState);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": reflowing ");
nsFrame::ListTag(stdout, aFrame);
printf(" prevBottomMargin=%d, collapsedTopMargin=%d => %d\n",
aPrevBottomMargin, topMargin,
MaxMargin(topMargin, aPrevBottomMargin));
#endif
// Collapse that value with the previous bottom margin to perform
// the sibling to sibling collaspe.
topMargin = MaxMargin(topMargin, aPrevBottomMargin);
// Adjust the available height if its constrained so that the
// child frame doesn't think it can reflow into its margin area.
if (aApplyTopMargin && (NS_UNCONSTRAINEDSIZE != aReflowState.availableHeight)) {
aReflowState.availableHeight -= topMargin;
}
}
mTopMargin = topMargin;
// 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 = aReflowState.mComputedMargin;
mStyleBorder = aReflowState.mStyleBorder;
mStyleMargin = aReflowState.mStyleMargin;
mStylePadding = aReflowState.mStylePadding;
nscoord x;
nscoord y = aSpace.y + topMargin;
// If it's a right floated element, then calculate the x-offset
// differently
if (NS_STYLE_FLOAT_RIGHT == aReflowState.mStyleDisplay->mFloats) {
nscoord frameWidth;
if (NS_UNCONSTRAINEDSIZE == aReflowState.mComputedWidth) {
nsSize frameSize;
// Use the current frame width
aFrame->GetSize(frameSize);
frameWidth = frameSize.width;
} else {
frameWidth = aReflowState.mComputedWidth +
aReflowState.mComputedBorderPadding.left +
aReflowState.mComputedBorderPadding.right;
}
// if this is an unconstrained width reflow, then just place the floater at the left margin
if (NS_UNCONSTRAINEDSIZE == aSpace.width)
x = aSpace.x;
else
x = aSpace.XMost() - mMargin.right - frameWidth;
} else {
x = aSpace.x + mMargin.left;
}
mX = x;
mY = y;
// If it's an auto-width table, then it doesn't behave like other blocks
// XXX why not for a floating table too?
if (mIsTable && !aReflowState.mStyleDisplay->IsFloating()) {
// If this isn't the table's initial reflow, then use its existing
// width to determine where it will be placed horizontally
if (aReflowState.reason != eReflowReason_Initial) {
nsBlockHorizontalAlign align;
nsSize size;
aFrame->GetSize(size);
align.mXOffset = x;
AlignBlockHorizontally(size.width, align);
// Don't reset "mX". because PlaceBlock() will recompute the
// x-offset and expects "mX" to be at the left margin edge
x = align.mXOffset;
}
}
// If the element is relatively positioned, then adjust x and y accordingly
if (NS_STYLE_POSITION_RELATIVE == aReflowState.mStyleDisplay->mPosition) {
x += aReflowState.mComputedOffsets.left;
y += aReflowState.mComputedOffsets.top;
}
// Let frame know that we are reflowing it
aFrame->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
aFrame->MoveTo(mPresContext, x, y);
nsIView* view;
aFrame->GetView(mPresContext, &view);
if (view) {
nsContainerFrame::PositionFrameView(mPresContext, aFrame, view);
}
#ifdef DEBUG
mMetrics.width = nscoord(0xdeadbeef);
mMetrics.height = nscoord(0xdeadbeef);
mMetrics.ascent = nscoord(0xdeadbeef);
mMetrics.descent = nscoord(0xdeadbeef);
if (nsnull != mMetrics.maxElementSize) {
mMetrics.maxElementSize->width = nscoord(0xdeadbeef);
mMetrics.maxElementSize->height = nscoord(0xdeadbeef);
}
#endif
// Adjust spacemanager coordinate system for the frame. The
// spacemanager coordinates are <b>inside</b> 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 <b>inside</b> 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;
mOuterReflowState.mSpaceManager->Translate(tx, ty);
// See if this is the child's initial reflow and we are supposed to
// compute our maximum width
if (mComputeMaximumWidth && (eReflowReason_Initial == aReason)) {
nscoord oldAvailableWidth = aReflowState.availableWidth;
nscoord oldComputedWidth = aReflowState.mComputedWidth;
aReflowState.availableWidth = NS_UNCONSTRAINEDSIZE;
aReflowState.mComputedWidth = NS_UNCONSTRAINEDSIZE;
rv = aFrame->Reflow(mPresContext, mMetrics, aReflowState,
aFrameReflowStatus);
// Update the reflow metrics with the maximum width
mMetrics.mMaximumWidth = mMetrics.width;
#ifdef NOISY_REFLOW
printf("*** nsBlockReflowContext::ReflowBlock block %p returning max width %d\n",
aFrame, mMetrics.mMaximumWidth);
#endif
// The second reflow is just as a resize reflow with the constrained
// width
aReflowState.availableWidth = oldAvailableWidth;
aReflowState.mComputedWidth = oldComputedWidth;
aReason = eReflowReason_Resize;
}
rv = aFrame->Reflow(mPresContext, mMetrics, aReflowState,
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, aFrame);
printf(" metrics=%d,%d!\n", mMetrics.width, mMetrics.height);
}
if ((nsnull != mMetrics.maxElementSize) &&
((nscoord(0xdeadbeef) == mMetrics.maxElementSize->width) ||
(nscoord(0xdeadbeef) == mMetrics.maxElementSize->height))) {
printf("nsBlockReflowContext: ");
nsFrame::ListTag(stdout, aFrame);
printf(" didn't set max-element-size!\n");
mMetrics.maxElementSize->width = 0;
mMetrics.maxElementSize->height = 0;
}
#ifdef REALLY_NOISY_MAX_ELEMENT_SIZE
// Note: there are common reflow situations where this *correctly*
// occurs; so only enable this debug noise when you really need to
// analyze in detail.
if ((nsnull != mMetrics.maxElementSize) &&
((mMetrics.maxElementSize->width > mMetrics.width) ||
(mMetrics.maxElementSize->height > mMetrics.height))) {
printf("nsBlockReflowContext: ");
nsFrame::ListTag(stdout, aFrame);
printf(": WARNING: maxElementSize=%d,%d > metrics=%d,%d\n",
mMetrics.maxElementSize->width,
mMetrics.maxElementSize->height,
mMetrics.width, mMetrics.height);
}
#endif
if ((mMetrics.width == nscoord(0xdeadbeef)) ||
(mMetrics.height == nscoord(0xdeadbeef)) ||
(mMetrics.ascent == nscoord(0xdeadbeef)) ||
(mMetrics.descent == nscoord(0xdeadbeef))) {
printf("nsBlockReflowContext: ");
nsFrame::ListTag(stdout, aFrame);
printf(" didn't set whad %d,%d,%d,%d!\n",
mMetrics.width, mMetrics.height,
mMetrics.ascent, mMetrics.descent);
}
}
#endif
#ifdef NOISY_MAX_ELEMENT_SIZE
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) {
if (nsnull != mMetrics.maxElementSize) {
printf(" ");
nsFrame::ListTag(stdout, aFrame);
printf(": maxElementSize=%d,%d wh=%d,%d\n",
mMetrics.maxElementSize->width,
mMetrics.maxElementSize->height,
mMetrics.width, mMetrics.height);
}
}
#endif
aFrame->GetFrameState(&state);
if (0 == (NS_FRAME_OUTSIDE_CHILDREN & state)) {
// 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;
}
// Now that frame has been reflowed at least one time make sure that
// the NS_FRAME_FIRST_REFLOW bit is cleared so that never give it an
// initial reflow reason again.
if (eReflowReason_Initial == aReason) {
aFrame->SetFrameState(state & ~NS_FRAME_FIRST_REFLOW);
}
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) {
// 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).
if (NS_FRAME_IS_COMPLETE(aFrameReflowStatus)) {
nsIFrame* kidNextInFlow;
aFrame->GetNextInFlow(&kidNextInFlow);
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)
/* XXX promote DeleteChildsNextInFlow to nsIFrame to elminate this cast */
nsHTMLContainerFrame* parent;
aFrame->GetParent((nsIFrame**)&parent);
parent->DeleteChildsNextInFlow(mPresContext, aFrame);
}
}
}
// If the block is shrink wrapping its width, then see if we have percentage
// based margins. If so, we can calculate them now that we know the shrink
// wrap width
if (NS_SHRINKWRAPWIDTH == aReflowState.mComputedWidth) {
ComputeShrinkwrapMargins(aReflowState.mStyleMargin, mMetrics.width, mMargin, mX);
}
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(PRBool aForceFit,
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect)
{
// Compute collapsed bottom margin value
nscoord collapsedBottomMargin = MaxMargin(mMetrics.mCarriedOutBottomMargin,
mMargin.bottom);
*aBottomMarginResult = collapsedBottomMargin;
// See if the block will fit in the available space
PRBool fits = PR_TRUE;
nscoord x = mX;
nscoord y = mY;
// When deciding whether it's empty we also need to take into
// account the overflow area
// XXXldb What should really matter is whether there exist non-
// empty frames in the block (with appropriate whitespace munging).
// Consider the case where we clip off the overflow with
// 'overflow: hidden' (which doesn't currently affect mOverflowArea,
// but probably should.
if ((0 == mMetrics.height) && (0 == mMetrics.mOverflowArea.height))
{
// Collapse the bottom margin with the top margin that was already
// applied.
nscoord newBottomMargin = MaxMargin(collapsedBottomMargin, mTopMargin);
*aBottomMarginResult = newBottomMargin;
#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
y = mSpace.y;
// Empty blocks do not have anything special done to them and they
// always fit. Note: don't force the width to 0
nsRect r(x, y, mMetrics.width, 0);
// Now place the frame and complete the reflow process
nsContainerFrame::FinishReflowChild(mFrame, mPresContext, mMetrics, x, y, 0);
aInFlowBounds = r;
// Retain combined area information in case we contain a floater
// and nothing else.
aCombinedRect = mMetrics.mOverflowArea;
aCombinedRect.x += x;
aCombinedRect.y += y;
}
else {
// See if the frame fit. If its the first frame then it always
// fits.
if (aForceFit || (y + mMetrics.height <= mSpace.YMost()))
{
// Calculate the actual x-offset and left and right margin
nsBlockHorizontalAlign align;
align.mXOffset = x;
AlignBlockHorizontally(mMetrics.width, align);
x = align.mXOffset;
mMargin.left = align.mLeftMargin;
mMargin.right = align.mRightMargin;
// Update the in-flow bounds rectangle
aInFlowBounds.SetRect(x, y,
mMetrics.width,
mMetrics.height);
// Compute combined-rect in callers coordinate system. The value
// returned in the reflow metrics is relative to the child
// frame.
aCombinedRect.x = mMetrics.mOverflowArea.x + x;
aCombinedRect.y = mMetrics.mOverflowArea.y + y;
aCombinedRect.width = mMetrics.mOverflowArea.width;
aCombinedRect.height = mMetrics.mOverflowArea.height;
// Apply CSS relative positioning to update x,y coordinates
// Note that this must be done after changing aCombinedRect
// since relatively positioned elements should act as if they
// were at their original position.
const nsStyleDisplay* styleDisp;
mFrame->GetStyleData(eStyleStruct_Display,
(const nsStyleStruct*&)styleDisp);
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, mMetrics, x, y, 0);
// Adjust the max-element-size in the metrics to take into
// account the margins around the block element. Note that we
// use the collapsed top and bottom margin values.
if (nsnull != mMetrics.maxElementSize) {
nsSize* m = mMetrics.maxElementSize;
nsMargin maxElemMargin = mMargin;
if (NS_SHRINKWRAPWIDTH == mComputedWidth) {
nscoord dummyXOffset;
// Base the margins on the max-element size
ComputeShrinkwrapMargins(mStyleMargin, m->width, maxElemMargin, dummyXOffset);
}
// Do not allow auto margins to impact the max-element size
// since they are springy and don't really count!
if (eStyleUnit_Auto != mStyleMargin->mMargin.GetLeftUnit()) {
m->width += maxElemMargin.left;
}
if (eStyleUnit_Auto != mStyleMargin->mMargin.GetRightUnit()) {
m->width += maxElemMargin.right;
}
#if 0 // XXX_fix_me
// Margin height should affect the max-element height (since
// auto top/bottom margins are always zero)
// XXXldb Should it?
m->height += mTopMargin + mBottomMargin;
#endif
}
}
else {
// Send the DidReflow() notification, but don't bother placing
// the frame
mFrame->DidReflow(mPresContext, NS_FRAME_REFLOW_FINISHED);
fits = PR_FALSE;
}
}
return fits;
}
// If we have an inherited margin its possible that its auto all the
// way up to the top of the tree. If that is the case, we need to know
// it.
nsStyleUnit
nsBlockReflowContext::GetRealMarginLeftUnit()
{
nsStyleUnit unit = eStyleUnit_Inherit;
nsIStyleContext* sc;
mFrame->GetStyleContext(&sc);
while ((nsnull != sc) && (eStyleUnit_Inherit == unit)) {
// Get parent style context
nsIStyleContext* psc;
psc = sc->GetParent();
NS_RELEASE(sc);
sc = psc;
if (nsnull != sc) {
const nsStyleMargin* margin = (const nsStyleMargin*)
sc->GetStyleData(eStyleStruct_Margin);
unit = margin->mMargin.GetLeftUnit();
}
}
NS_IF_RELEASE(sc);
return unit;
}
// If we have an inherited margin its possible that its auto all the
// way up to the top of the tree. If that is the case, we need to know
// it.
nsStyleUnit
nsBlockReflowContext::GetRealMarginRightUnit()
{
nsStyleUnit unit = eStyleUnit_Inherit;
nsIStyleContext* sc;
mFrame->GetStyleContext(&sc);
while ((nsnull != sc) && (eStyleUnit_Inherit == unit)) {
// Get parent style context
nsIStyleContext* psc;
psc = sc->GetParent();
NS_RELEASE(sc);
sc = psc;
if (nsnull != sc) {
const nsStyleMargin* margin = (const nsStyleMargin*)
sc->GetStyleData(eStyleStruct_Margin);
unit = margin->mMargin.GetRightUnit();
}
}
NS_IF_RELEASE(sc);
return unit;
}