gecko-dev/layout/generic/nsBlockReflowContext.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
// vim:cindent:ts=2:et:sw=2:
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* 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 the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* David Baron <dbaron@fas.harvard.edu>
*
* Alternatively, the contents of this file may be used under the terms of
* either 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 NPL, 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 NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsBlockReflowContext.h"
#include "nsLineLayout.h"
#include "nsSpaceManager.h"
#include "nsIFontMetrics.h"
#include "nsIPresContext.h"
#include "nsIContent.h"
#include "nsIStyleContext.h"
#include "nsHTMLReflowCommand.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;
}
void
nsBlockReflowContext::ComputeCollapsedTopMargin(nsIPresContext* aPresContext,
nsHTMLReflowState& aRS,
/* inout */ nsCollapsingMargin& aMargin)
{
// Get aFrame's top margin
aMargin.Include(aRS.mComputedMargin.top);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, aRS.frame);
printf(": %d => %d\n", aRS.mComputedMargin.top, aMargin.get());
#endif
// 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.
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,
NS_REINTERPRET_CAST(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 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. Since the reflow reason is irrelevant, we'll
// arbitrarily make it a `resize' to avoid the path-plucking
// behavior if we're in an incremental reflow.
nsSize availSpace(aRS.mComputedWidth, aRS.mComputedHeight);
nsHTMLReflowState reflowState(aPresContext, aRS, childFrame,
availSpace, eReflowReason_Resize);
ComputeCollapsedTopMargin(aPresContext, reflowState, aMargin);
}
}
}
}
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, aRS.frame);
printf(": => %d\n", aMargin.get());
#endif
}
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 = mSpace.x;
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
//}
}
}
}
}
}
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::ReflowBlock(const nsRect& aSpace,
PRBool aApplyTopMargin,
nsCollapsingMargin& aPrevBottomMargin,
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsHTMLReflowState& aFrameRS,
nsReflowStatus& aFrameReflowStatus)
{
nsresult rv = NS_OK;
mFrame = aFrameRS.frame;
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.
aFrameRS.reason = eReflowReason_Resize;
nsFrameState state;
mFrame->GetFrameState(&state);
if (NS_FRAME_FIRST_REFLOW & state) {
aFrameRS.reason = eReflowReason_Initial;
}
else if (mOuterReflowState.reason == eReflowReason_Incremental) {
// If the frame we're about to reflow is on the reflow path, then
// propagate the reflow as `incremental' so it unwinds correctly
// to the target frames below us.
PRBool frameIsOnReflowPath = mOuterReflowState.path->HasChild(mFrame);
if (frameIsOnReflowPath)
aFrameRS.reason = eReflowReason_Incremental;
// But...if the incremental reflow command is a StyleChanged
// reflow and its target is the current block, change the reason
// to `style change', so that it propagates through the entire
// subtree.
nsHTMLReflowCommand* rc = mOuterReflowState.path->mReflowCommand;
if (rc) {
nsReflowType type;
rc->GetType(type);
if (type == eReflowType_StyleChanged)
aFrameRS.reason = eReflowReason_StyleChange;
else if (type == eReflowType_ReflowDirty &&
(state & NS_FRAME_IS_DIRTY) &&
!frameIsOnReflowPath) {
aFrameRS.reason = eReflowReason_Dirty;
}
}
}
else if (mOuterReflowState.reason == eReflowReason_StyleChange) {
aFrameRS.reason = eReflowReason_StyleChange;
}
else if (mOuterReflowState.reason == eReflowReason_Dirty) {
if (state & NS_FRAME_IS_DIRTY)
aFrameRS.reason = eReflowReason_Dirty;
}
/* 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;
mFrame->GetStyleData(eStyleStruct_Position, (const nsStyleStruct*&)position);
nsStyleUnit widthUnit = position->mWidth.GetUnit();
const nsStyleDisplay* display;
mFrame->GetStyleData(eStyleStruct_Display, (const nsStyleStruct*&)display);
if ((eStyleUnit_Auto == widthUnit) &&
((NS_STYLE_FLOAT_LEFT == display->mFloats) ||
(NS_STYLE_FLOAT_RIGHT == display->mFloats))) {
// Initialize the reflow state and constrain the containing block's
// width and height to the available width and height.
aFrameRS.Init(mPresContext, mSpace.width, mSpace.height);
}
else {
// Initialize the reflow state and use the containing block's computed
// width and height (or derive appropriate values for an
// absolutely positioned frame).
aFrameRS.Init(mPresContext);
}
aComputedOffsets = aFrameRS.mComputedOffsets;
aFrameRS.mLineLayout = nsnull;
if (!aIsAdjacentWithTop) {
aFrameRS.mFlags.mIsTopOfPage = PR_FALSE; // make sure this is cleared
}
mIsTable = NS_STYLE_DISPLAY_TABLE == aFrameRS.mStyleDisplay->mDisplay;
mComputedWidth = aFrameRS.mComputedWidth;
if (aApplyTopMargin) {
// Compute the childs collapsed top margin (its margin collpased
// with its first childs top-margin -- recursively).
ComputeCollapsedTopMargin(mPresContext, aFrameRS, aPrevBottomMargin);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": reflowing ");
nsFrame::ListTag(stdout, mFrame);
printf(" margin => %d\n", aPrevBottomMargin.get());
#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 -= aPrevBottomMargin.get();
}
}
mTopMargin = aPrevBottomMargin.get();
// 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;
// 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.mComputedWidth) {
nsSize frameSize;
// Use the current frame width
mFrame->GetSize(frameSize);
frameWidth = frameSize.width;
} else {
frameWidth = aFrameRS.mComputedWidth +
aFrameRS.mComputedBorderPadding.left +
aFrameRS.mComputedBorderPadding.right;
}
// if this is an unconstrained width reflow, then just place the floater 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;
// 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 && !aFrameRS.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 (aFrameRS.reason != eReflowReason_Initial) {
nsBlockHorizontalAlign align;
nsSize size;
mFrame->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 == 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
mFrame->MoveTo(mPresContext, x, y);
nsContainerFrame::PositionFrameView(mPresContext, mFrame);
#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 == aFrameRS.reason)) {
mOuterReflowState.mSpaceManager->PushState();
nscoord oldAvailableWidth = aFrameRS.availableWidth;
nscoord oldComputedWidth = aFrameRS.mComputedWidth;
aFrameRS.availableWidth = NS_UNCONSTRAINEDSIZE;
aFrameRS.mComputedWidth = NS_UNCONSTRAINEDSIZE;
rv = mFrame->Reflow(mPresContext, mMetrics, aFrameRS, 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",
mFrame, mMetrics.mMaximumWidth);
#endif
// The second reflow is just as a resize reflow with the constrained
// width
aFrameRS.availableWidth = oldAvailableWidth;
aFrameRS.mComputedWidth = oldComputedWidth;
aFrameRS.reason = eReflowReason_Resize;
mOuterReflowState.mSpaceManager->PopState();
}
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 ((nsnull != mMetrics.maxElementSize) &&
((nscoord(0xdeadbeef) == mMetrics.maxElementSize->width) ||
(nscoord(0xdeadbeef) == mMetrics.maxElementSize->height))) {
printf("nsBlockReflowContext: ");
nsFrame::ListTag(stdout, mFrame);
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, mFrame);
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, mFrame);
printf(" didn't set whad %d,%d,%d,%d!\n",
mMetrics.width, mMetrics.height,
mMetrics.ascent, mMetrics.descent);
}
}
#endif
#ifdef DEBUG
if (nsBlockFrame::gNoisyMaxElementSize) {
nsFrame::IndentBy(stdout, nsBlockFrame::gNoiseIndent);
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) {
if (nsnull != mMetrics.maxElementSize) {
printf(" ");
nsFrame::ListTag(stdout, mFrame);
printf(": maxElementSize=%d,%d wh=%d,%d\n",
mMetrics.maxElementSize->width,
mMetrics.maxElementSize->height,
mMetrics.width, mMetrics.height);
}
}
}
#endif
mFrame->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 == aFrameRS.reason) {
mFrame->SetFrameState(state & ~NS_FRAME_FIRST_REFLOW);
}
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus) ||
(state & 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(&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;
mFrame->GetParent((nsIFrame**)&parent);
parent->DeleteChildsNextInFlow(mPresContext, mFrame);
}
}
}
// 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 == aFrameRS.mComputedWidth) {
ComputeShrinkwrapMargins(aFrameRS.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(const nsHTMLReflowState& aReflowState,
PRBool aForceFit,
const nsMargin& aComputedOffsets,
nsCollapsingMargin& aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect)
{
// Compute collapsed bottom margin value
aBottomMarginResult = mMetrics.mCarriedOutBottomMargin;
aBottomMarginResult.Include(mMargin.bottom);
// 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.
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
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, &aReflowState, 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, &aReflowState, 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()) &&
(eStyleUnit_Null != mStyleMargin->mMargin.GetLeftUnit())) {
m->width += maxElemMargin.left;
}
if ((eStyleUnit_Auto != mStyleMargin->mMargin.GetRightUnit()) &&
(eStyleUnit_Null != 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, &aReflowState, 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;
}