зеркало из https://github.com/mozilla/gecko-dev.git
2995 строки
119 KiB
C++
2995 строки
119 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=2 et sw=2 tw=80: */
|
|
|
|
/* This Source Code is subject to the terms of the Mozilla Public License
|
|
* version 2.0 (the "License"). You can obtain a copy of the License at
|
|
* http://mozilla.org/MPL/2.0/. */
|
|
|
|
/* rendering object for CSS "display: flex" */
|
|
|
|
#include "nsFlexContainerFrame.h"
|
|
#include "nsContentUtils.h"
|
|
#include "nsCSSAnonBoxes.h"
|
|
#include "nsDisplayList.h"
|
|
#include "nsLayoutUtils.h"
|
|
#include "nsPlaceholderFrame.h"
|
|
#include "nsPresContext.h"
|
|
#include "nsStyleContext.h"
|
|
#include "prlog.h"
|
|
#include <algorithm>
|
|
|
|
using namespace mozilla::css;
|
|
using namespace mozilla::layout;
|
|
|
|
#ifdef PR_LOGGING
|
|
static PRLogModuleInfo*
|
|
GetFlexContainerLog()
|
|
{
|
|
static PRLogModuleInfo *sLog;
|
|
if (!sLog)
|
|
sLog = PR_NewLogModule("nsFlexContainerFrame");
|
|
return sLog;
|
|
}
|
|
#endif /* PR_LOGGING */
|
|
|
|
// XXXdholbert Some of this helper-stuff should be separated out into a general
|
|
// "LogicalAxisUtils.h" helper. Should that be a class, or a namespace (under
|
|
// what super-namespace?), or what?
|
|
|
|
// Helper enums
|
|
// ============
|
|
|
|
// Represents a physical orientation for an axis.
|
|
// The directional suffix indicates the direction in which the axis *grows*.
|
|
// So e.g. eAxis_LR means a horizontal left-to-right axis, whereas eAxis_BT
|
|
// means a vertical bottom-to-top axis.
|
|
// NOTE: The order here is important -- these values are used as indices into
|
|
// the static array 'kAxisOrientationToSidesMap', defined below.
|
|
enum AxisOrientationType {
|
|
eAxis_LR,
|
|
eAxis_RL,
|
|
eAxis_TB,
|
|
eAxis_BT,
|
|
eNumAxisOrientationTypes // For sizing arrays that use these values as indices
|
|
};
|
|
|
|
// Represents one or the other extreme of an axis (e.g. for the main axis, the
|
|
// main-start vs. main-end edge.
|
|
// NOTE: The order here is important -- these values are used as indices into
|
|
// the sub-arrays in 'kAxisOrientationToSidesMap', defined below.
|
|
enum AxisEdgeType {
|
|
eAxisEdge_Start,
|
|
eAxisEdge_End,
|
|
eNumAxisEdges // For sizing arrays that use these values as indices
|
|
};
|
|
|
|
// This array maps each axis orientation to a pair of corresponding
|
|
// [start, end] physical mozilla::css::Side values.
|
|
static const Side
|
|
kAxisOrientationToSidesMap[eNumAxisOrientationTypes][eNumAxisEdges] = {
|
|
{ eSideLeft, eSideRight }, // eAxis_LR
|
|
{ eSideRight, eSideLeft }, // eAxis_RL
|
|
{ eSideTop, eSideBottom }, // eAxis_TB
|
|
{ eSideBottom, eSideTop } // eAxis_BT
|
|
};
|
|
|
|
// Helper structs / classes / methods
|
|
// ==================================
|
|
|
|
// Indicates whether advancing along the given axis is equivalent to
|
|
// increasing our X or Y position (as opposed to decreasing it).
|
|
static inline bool
|
|
AxisGrowsInPositiveDirection(AxisOrientationType aAxis)
|
|
{
|
|
return eAxis_LR == aAxis || eAxis_TB == aAxis;
|
|
}
|
|
|
|
// Indicates whether the given axis is horizontal.
|
|
static inline bool
|
|
IsAxisHorizontal(AxisOrientationType aAxis)
|
|
{
|
|
return eAxis_LR == aAxis || eAxis_RL == aAxis;
|
|
}
|
|
|
|
// Given an AxisOrientationType, returns the "reverse" AxisOrientationType
|
|
// (in the same dimension, but the opposite direction)
|
|
static inline AxisOrientationType
|
|
GetReverseAxis(AxisOrientationType aAxis)
|
|
{
|
|
AxisOrientationType reversedAxis;
|
|
|
|
if (aAxis % 2 == 0) {
|
|
// even enum value. Add 1 to reverse.
|
|
reversedAxis = AxisOrientationType(aAxis + 1);
|
|
} else {
|
|
// odd enum value. Subtract 1 to reverse.
|
|
reversedAxis = AxisOrientationType(aAxis - 1);
|
|
}
|
|
|
|
// Check that we're still in the enum's valid range
|
|
MOZ_ASSERT(reversedAxis >= eAxis_LR &&
|
|
reversedAxis <= eAxis_BT);
|
|
|
|
return reversedAxis;
|
|
}
|
|
|
|
// Returns aFrame's computed value for 'height' or 'width' -- whichever is in
|
|
// the same dimension as aAxis.
|
|
static inline const nsStyleCoord&
|
|
GetSizePropertyForAxis(const nsIFrame* aFrame, AxisOrientationType aAxis)
|
|
{
|
|
const nsStylePosition* stylePos = aFrame->StylePosition();
|
|
|
|
return IsAxisHorizontal(aAxis) ?
|
|
stylePos->mWidth :
|
|
stylePos->mHeight;
|
|
}
|
|
|
|
/**
|
|
* Converts a logical position in a given axis into a position in the
|
|
* corresponding physical (x or y) axis. If the logical axis already maps
|
|
* directly onto one of our physical axes (i.e. LTR or TTB), then the logical
|
|
* and physical positions are equal; otherwise, we subtract the logical
|
|
* position from the container-size in that axis, to flip the polarity.
|
|
* (so e.g. a logical position of 2px in a RTL 20px-wide container
|
|
* would correspond to a physical position of 18px.)
|
|
*/
|
|
static nscoord
|
|
PhysicalPosFromLogicalPos(nscoord aLogicalPosn,
|
|
nscoord aLogicalContainerSize,
|
|
AxisOrientationType aAxis) {
|
|
if (AxisGrowsInPositiveDirection(aAxis)) {
|
|
return aLogicalPosn;
|
|
}
|
|
return aLogicalContainerSize - aLogicalPosn;
|
|
}
|
|
|
|
static nscoord
|
|
MarginComponentForSide(const nsMargin& aMargin, Side aSide)
|
|
{
|
|
switch (aSide) {
|
|
case eSideLeft:
|
|
return aMargin.left;
|
|
case eSideRight:
|
|
return aMargin.right;
|
|
case eSideTop:
|
|
return aMargin.top;
|
|
case eSideBottom:
|
|
return aMargin.bottom;
|
|
}
|
|
|
|
NS_NOTREACHED("unexpected Side enum");
|
|
return aMargin.left; // have to return something
|
|
// (but something's busted if we got here)
|
|
}
|
|
|
|
static nscoord&
|
|
MarginComponentForSide(nsMargin& aMargin, Side aSide)
|
|
{
|
|
switch (aSide) {
|
|
case eSideLeft:
|
|
return aMargin.left;
|
|
case eSideRight:
|
|
return aMargin.right;
|
|
case eSideTop:
|
|
return aMargin.top;
|
|
case eSideBottom:
|
|
return aMargin.bottom;
|
|
}
|
|
|
|
NS_NOTREACHED("unexpected Side enum");
|
|
return aMargin.left; // have to return something
|
|
// (but something's busted if we got here)
|
|
}
|
|
|
|
// Helper-macro to let us pick one of two expressions to evaluate
|
|
// (a width expression vs. a height expression), to get a main-axis or
|
|
// cross-axis component.
|
|
// For code that has e.g. a nsSize object, FlexboxAxisTracker::GetMainComponent
|
|
// and GetCrossComponent are cleaner; but in cases where we simply have
|
|
// two separate expressions for width and height (which may be expensive to
|
|
// evaluate), these macros will ensure that only the expression for the correct
|
|
// axis gets evaluated.
|
|
#define GET_MAIN_COMPONENT(axisTracker_, width_, height_) \
|
|
IsAxisHorizontal((axisTracker_).GetMainAxis()) ? (width_) : (height_)
|
|
|
|
#define GET_CROSS_COMPONENT(axisTracker_, width_, height_) \
|
|
IsAxisHorizontal((axisTracker_).GetCrossAxis()) ? (width_) : (height_)
|
|
|
|
// Encapsulates our flex container's main & cross axes.
|
|
class MOZ_STACK_CLASS FlexboxAxisTracker {
|
|
public:
|
|
FlexboxAxisTracker(nsFlexContainerFrame* aFlexContainerFrame);
|
|
|
|
// Accessors:
|
|
AxisOrientationType GetMainAxis() const { return mMainAxis; }
|
|
AxisOrientationType GetCrossAxis() const { return mCrossAxis; }
|
|
|
|
nscoord GetMainComponent(const nsSize& aSize) const {
|
|
return GET_MAIN_COMPONENT(*this, aSize.width, aSize.height);
|
|
}
|
|
int32_t GetMainComponent(const nsIntSize& aIntSize) const {
|
|
return GET_MAIN_COMPONENT(*this, aIntSize.width, aIntSize.height);
|
|
}
|
|
|
|
nscoord GetCrossComponent(const nsSize& aSize) const {
|
|
return GET_CROSS_COMPONENT(*this, aSize.width, aSize.height);
|
|
}
|
|
int32_t GetCrossComponent(const nsIntSize& aIntSize) const {
|
|
return GET_CROSS_COMPONENT(*this, aIntSize.width, aIntSize.height);
|
|
}
|
|
|
|
nscoord GetMarginSizeInMainAxis(const nsMargin& aMargin) const {
|
|
return IsAxisHorizontal(mMainAxis) ?
|
|
aMargin.LeftRight() :
|
|
aMargin.TopBottom();
|
|
}
|
|
nscoord GetMarginSizeInCrossAxis(const nsMargin& aMargin) const {
|
|
return IsAxisHorizontal(mCrossAxis) ?
|
|
aMargin.LeftRight() :
|
|
aMargin.TopBottom();
|
|
}
|
|
|
|
/**
|
|
* Converts a logical point into a "physical" x,y point.
|
|
*
|
|
* In the simplest case where the main-axis is left-to-right and the
|
|
* cross-axis is top-to-bottom, this just returns
|
|
* nsPoint(aMainPosn, aCrossPosn).
|
|
*
|
|
* @arg aMainPosn The main-axis position -- i.e an offset from the
|
|
* main-start edge of the container's content box.
|
|
* @arg aCrossPosn The cross-axis position -- i.e an offset from the
|
|
* cross-start edge of the container's content box.
|
|
* @return A nsPoint representing the same position (in coordinates
|
|
* relative to the container's content box).
|
|
*/
|
|
nsPoint PhysicalPointFromLogicalPoint(nscoord aMainPosn,
|
|
nscoord aCrossPosn,
|
|
nscoord aContainerMainSize,
|
|
nscoord aContainerCrossSize) const {
|
|
nscoord physicalPosnInMainAxis =
|
|
PhysicalPosFromLogicalPos(aMainPosn, aContainerMainSize, mMainAxis);
|
|
nscoord physicalPosnInCrossAxis =
|
|
PhysicalPosFromLogicalPos(aCrossPosn, aContainerCrossSize, mCrossAxis);
|
|
|
|
return IsAxisHorizontal(mMainAxis) ?
|
|
nsPoint(physicalPosnInMainAxis, physicalPosnInCrossAxis) :
|
|
nsPoint(physicalPosnInCrossAxis, physicalPosnInMainAxis);
|
|
}
|
|
nsSize PhysicalSizeFromLogicalSizes(nscoord aMainSize,
|
|
nscoord aCrossSize) const {
|
|
return IsAxisHorizontal(mMainAxis) ?
|
|
nsSize(aMainSize, aCrossSize) :
|
|
nsSize(aCrossSize, aMainSize);
|
|
}
|
|
|
|
private:
|
|
AxisOrientationType mMainAxis;
|
|
AxisOrientationType mCrossAxis;
|
|
};
|
|
|
|
// Represents a flex item.
|
|
// Includes the various pieces of input that the Flexbox Layout Algorithm uses
|
|
// to resolve a flexible width.
|
|
class FlexItem {
|
|
public:
|
|
FlexItem(nsIFrame* aChildFrame,
|
|
float aFlexGrow, float aFlexShrink, nscoord aMainBaseSize,
|
|
nscoord aMainMinSize, nscoord aMainMaxSize,
|
|
nscoord aCrossMinSize, nscoord aCrossMaxSize,
|
|
nsMargin aMargin, nsMargin aBorderPadding,
|
|
const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
// Accessors
|
|
nsIFrame* Frame() const { return mFrame; }
|
|
nscoord GetFlexBaseSize() const { return mFlexBaseSize; }
|
|
|
|
nscoord GetMainMinSize() const { return mMainMinSize; }
|
|
nscoord GetMainMaxSize() const { return mMainMaxSize; }
|
|
|
|
// Note: These return the main-axis position and size of our *content box*.
|
|
nscoord GetMainSize() const { return mMainSize; }
|
|
nscoord GetMainPosition() const { return mMainPosn; }
|
|
|
|
nscoord GetCrossMinSize() const { return mCrossMinSize; }
|
|
nscoord GetCrossMaxSize() const { return mCrossMaxSize; }
|
|
|
|
// Note: These return the cross-axis position and size of our *content box*.
|
|
nscoord GetCrossSize() const { return mCrossSize; }
|
|
nscoord GetCrossPosition() const { return mCrossPosn; }
|
|
|
|
// Returns the distance between this FlexItem's baseline and the cross-start
|
|
// edge of its margin-box. Used in baseline alignment.
|
|
// (This function needs to be told what the cross axis is so that it can
|
|
// look up the appropriate component from mMargin.)
|
|
nscoord GetBaselineOffsetFromOuterCrossStart(
|
|
AxisOrientationType aCrossAxis) const;
|
|
|
|
float GetShareOfFlexWeightSoFar() const { return mShareOfFlexWeightSoFar; }
|
|
|
|
bool IsFrozen() const { return mIsFrozen; }
|
|
|
|
bool HadMinViolation() const { return mHadMinViolation; }
|
|
bool HadMaxViolation() const { return mHadMaxViolation; }
|
|
|
|
// Indicates whether this item received a preliminary "measuring" reflow
|
|
// before its actual reflow.
|
|
bool HadMeasuringReflow() const { return mHadMeasuringReflow; }
|
|
|
|
// Indicates whether this item's cross-size has been stretched (from having
|
|
// "align-self: stretch" with an auto cross-size and no auto margins in the
|
|
// cross axis).
|
|
bool IsStretched() const { return mIsStretched; }
|
|
|
|
uint8_t GetAlignSelf() const { return mAlignSelf; }
|
|
|
|
// Returns the flex weight that we should use in the "resolving flexible
|
|
// lengths" algorithm. If we're using flex grow, we just return that;
|
|
// otherwise, we use the "scaled flex shrink weight" (scaled by our flex
|
|
// base size, so that when both large and small items are shrinking,
|
|
// the large items shrink more).
|
|
float GetFlexWeightToUse(bool aIsUsingFlexGrow)
|
|
{
|
|
if (IsFrozen()) {
|
|
return 0.0f;
|
|
}
|
|
|
|
if (aIsUsingFlexGrow) {
|
|
return mFlexGrow;
|
|
}
|
|
|
|
// We're using flex-shrink --> return mFlexShrink * mFlexBaseSize
|
|
if (mFlexBaseSize == 0) {
|
|
// Special-case for mFlexBaseSize == 0 -- we have no room to shrink, so
|
|
// regardless of mFlexShrink, we should just return 0.
|
|
// (This is really a special-case for when mFlexShrink is infinity, to
|
|
// avoid performing mFlexShrink * mFlexBaseSize = inf * 0 = undefined.)
|
|
return 0.0f;
|
|
}
|
|
return mFlexShrink * mFlexBaseSize;
|
|
}
|
|
|
|
// Getters for margin:
|
|
// ===================
|
|
const nsMargin& GetMargin() const { return mMargin; }
|
|
|
|
// Returns the margin component for a given mozilla::css::Side
|
|
nscoord GetMarginComponentForSide(Side aSide) const
|
|
{ return MarginComponentForSide(mMargin, aSide); }
|
|
|
|
// Returns the total space occupied by this item's margins in the given axis
|
|
nscoord GetMarginSizeInAxis(AxisOrientationType aAxis) const
|
|
{
|
|
Side startSide = kAxisOrientationToSidesMap[aAxis][eAxisEdge_Start];
|
|
Side endSide = kAxisOrientationToSidesMap[aAxis][eAxisEdge_End];
|
|
return GetMarginComponentForSide(startSide) +
|
|
GetMarginComponentForSide(endSide);
|
|
}
|
|
|
|
// Getters for border/padding
|
|
// ==========================
|
|
const nsMargin& GetBorderPadding() const { return mBorderPadding; }
|
|
|
|
// Returns the border+padding component for a given mozilla::css::Side
|
|
nscoord GetBorderPaddingComponentForSide(Side aSide) const
|
|
{ return MarginComponentForSide(mBorderPadding, aSide); }
|
|
|
|
// Returns the total space occupied by this item's borders and padding in
|
|
// the given axis
|
|
nscoord GetBorderPaddingSizeInAxis(AxisOrientationType aAxis) const
|
|
{
|
|
Side startSide = kAxisOrientationToSidesMap[aAxis][eAxisEdge_Start];
|
|
Side endSide = kAxisOrientationToSidesMap[aAxis][eAxisEdge_End];
|
|
return GetBorderPaddingComponentForSide(startSide) +
|
|
GetBorderPaddingComponentForSide(endSide);
|
|
}
|
|
|
|
// Getter for combined margin/border/padding
|
|
// =========================================
|
|
// Returns the total space occupied by this item's margins, borders and
|
|
// padding in the given axis
|
|
nscoord GetMarginBorderPaddingSizeInAxis(AxisOrientationType aAxis) const
|
|
{
|
|
return GetMarginSizeInAxis(aAxis) + GetBorderPaddingSizeInAxis(aAxis);
|
|
}
|
|
|
|
// Setters
|
|
// =======
|
|
|
|
// This sets our flex base size, and then updates the main size to the
|
|
// base size clamped to our main-axis [min,max] constraints.
|
|
void SetFlexBaseSizeAndMainSize(nscoord aNewFlexBaseSize)
|
|
{
|
|
MOZ_ASSERT(!mIsFrozen || mFlexBaseSize == NS_INTRINSICSIZE,
|
|
"flex base size shouldn't change after we're frozen "
|
|
"(unless we're just resolving an intrinsic size)");
|
|
mFlexBaseSize = aNewFlexBaseSize;
|
|
|
|
// Before we've resolved flexible lengths, we keep mMainSize set to
|
|
// the 'hypothetical main size', which is the flex base size, clamped
|
|
// to the [min,max] range:
|
|
mMainSize = NS_CSS_MINMAX(mFlexBaseSize, mMainMinSize, mMainMaxSize);
|
|
}
|
|
|
|
// Setters used while we're resolving flexible lengths
|
|
// ---------------------------------------------------
|
|
|
|
// Sets the main-size of our flex item's content-box.
|
|
void SetMainSize(nscoord aNewMainSize)
|
|
{
|
|
MOZ_ASSERT(!mIsFrozen, "main size shouldn't change after we're frozen");
|
|
mMainSize = aNewMainSize;
|
|
}
|
|
|
|
void SetShareOfFlexWeightSoFar(float aNewShare)
|
|
{
|
|
MOZ_ASSERT(!mIsFrozen || aNewShare == 0.0f,
|
|
"shouldn't be giving this item any share of the weight "
|
|
"after it's frozen");
|
|
mShareOfFlexWeightSoFar = aNewShare;
|
|
}
|
|
|
|
void Freeze() { mIsFrozen = true; }
|
|
|
|
void SetHadMinViolation()
|
|
{
|
|
MOZ_ASSERT(!mIsFrozen,
|
|
"shouldn't be changing main size & having violations "
|
|
"after we're frozen");
|
|
mHadMinViolation = true;
|
|
}
|
|
void SetHadMaxViolation()
|
|
{
|
|
MOZ_ASSERT(!mIsFrozen,
|
|
"shouldn't be changing main size & having violations "
|
|
"after we're frozen");
|
|
mHadMaxViolation = true;
|
|
}
|
|
void ClearViolationFlags()
|
|
{ mHadMinViolation = mHadMaxViolation = false; }
|
|
|
|
// Setters for values that are determined after we've resolved our main size
|
|
// -------------------------------------------------------------------------
|
|
|
|
// Sets the main-axis position of our flex item's content-box.
|
|
// (This is the distance between the main-start edge of the flex container
|
|
// and the main-start edge of the flex item's content-box.)
|
|
void SetMainPosition(nscoord aPosn) {
|
|
MOZ_ASSERT(mIsFrozen, "main size should be resolved before this");
|
|
mMainPosn = aPosn;
|
|
}
|
|
|
|
// Sets the cross-size of our flex item's content-box.
|
|
void SetCrossSize(nscoord aCrossSize) {
|
|
MOZ_ASSERT(!mIsStretched,
|
|
"Cross size shouldn't be modified after it's been stretched");
|
|
mCrossSize = aCrossSize;
|
|
}
|
|
|
|
// Sets the cross-axis position of our flex item's content-box.
|
|
// (This is the distance between the cross-start edge of the flex container
|
|
// and the cross-start edge of the flex item.)
|
|
void SetCrossPosition(nscoord aPosn) {
|
|
MOZ_ASSERT(mIsFrozen, "main size should be resolved before this");
|
|
mCrossPosn = aPosn;
|
|
}
|
|
|
|
void SetAscent(nscoord aAscent) {
|
|
mAscent = aAscent;
|
|
}
|
|
|
|
void SetHadMeasuringReflow() {
|
|
mHadMeasuringReflow = true;
|
|
}
|
|
|
|
void SetIsStretched() {
|
|
MOZ_ASSERT(mIsFrozen, "main size should be resolved before this");
|
|
mIsStretched = true;
|
|
}
|
|
|
|
// Setter for margin components (for resolving "auto" margins)
|
|
void SetMarginComponentForSide(Side aSide, nscoord aLength)
|
|
{
|
|
MOZ_ASSERT(mIsFrozen, "main size should be resolved before this");
|
|
MarginComponentForSide(mMargin, aSide) = aLength;
|
|
}
|
|
|
|
void ResolveStretchedCrossSize(nscoord aLineCrossSize,
|
|
const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
uint32_t GetNumAutoMarginsInAxis(AxisOrientationType aAxis) const;
|
|
|
|
protected:
|
|
// Our frame:
|
|
nsIFrame* const mFrame;
|
|
|
|
// Values that we already know in constructor: (and are hence mostly 'const')
|
|
const float mFlexGrow;
|
|
const float mFlexShrink;
|
|
|
|
const nsMargin mBorderPadding;
|
|
nsMargin mMargin; // non-const because we need to resolve auto margins
|
|
|
|
nscoord mFlexBaseSize;
|
|
|
|
const nscoord mMainMinSize;
|
|
const nscoord mMainMaxSize;
|
|
const nscoord mCrossMinSize;
|
|
const nscoord mCrossMaxSize;
|
|
|
|
// Values that we compute after constructor:
|
|
nscoord mMainSize;
|
|
nscoord mMainPosn;
|
|
nscoord mCrossSize;
|
|
nscoord mCrossPosn;
|
|
nscoord mAscent;
|
|
|
|
// Temporary state, while we're resolving flexible widths (for our main size)
|
|
// XXXdholbert To save space, we could use a union to make these variables
|
|
// overlay the same memory as some other member vars that aren't touched
|
|
// until after main-size has been resolved. In particular, these could share
|
|
// memory with mMainPosn through mAscent, and mIsStretched.
|
|
float mShareOfFlexWeightSoFar;
|
|
bool mIsFrozen;
|
|
bool mHadMinViolation;
|
|
bool mHadMaxViolation;
|
|
|
|
// Misc:
|
|
bool mHadMeasuringReflow; // Did this item get a preliminary reflow,
|
|
// to measure its desired height?
|
|
bool mIsStretched; // See IsStretched() documentation
|
|
uint8_t mAlignSelf; // My "align-self" computed value (with "auto"
|
|
// swapped out for parent"s "align-items" value,
|
|
// in our constructor).
|
|
};
|
|
|
|
// Represents a single flex line in a flex container.
|
|
// Manages an array of the FlexItems that are in the line.
|
|
class FlexLine {
|
|
public:
|
|
FlexLine()
|
|
: mTotalInnerHypotheticalMainSize(0),
|
|
mTotalOuterHypotheticalMainSize(0),
|
|
mLineCrossSize(0),
|
|
mBaselineOffsetFromCrossStart(nscoord_MIN)
|
|
{}
|
|
|
|
// Returns the sum of our FlexItems' outer hypothetical main sizes.
|
|
// ("outer" = margin-box, and "hypothetical" = before flexing)
|
|
nscoord GetTotalOuterHypotheticalMainSize() const {
|
|
return mTotalOuterHypotheticalMainSize;
|
|
}
|
|
|
|
// Adds a new FlexItem's hypothetical main sizes to our totals.
|
|
// (Should only be called when a FlexItem is being appended to this line.)
|
|
void AddToMainSizeTotals(nscoord aItemInnerHypotheticalMainSize,
|
|
nscoord aItemOuterHypotheticalMainSize) {
|
|
mTotalInnerHypotheticalMainSize += aItemInnerHypotheticalMainSize;
|
|
mTotalOuterHypotheticalMainSize += aItemOuterHypotheticalMainSize;
|
|
}
|
|
|
|
// Computes the cross-size and baseline position of this FlexLine, based on
|
|
// its FlexItems.
|
|
void ComputeCrossSizeAndBaseline(const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
// Returns the cross-size of this line.
|
|
nscoord GetLineCrossSize() const { return mLineCrossSize; }
|
|
|
|
// Setter for line cross-size -- needed for cases where the flex container
|
|
// imposes a cross-size on the line. (e.g. for single-line flexbox, or for
|
|
// multi-line flexbox with 'align-content: stretch')
|
|
void SetLineCrossSize(nscoord aLineCrossSize) {
|
|
mLineCrossSize = aLineCrossSize;
|
|
}
|
|
|
|
// Returns the distance from the cross-start edge of this FlexLine
|
|
// to its baseline (derived from its baseline-aligned FlexItems).
|
|
// If there are no baseline-aligned FlexItems, returns nscoord_MIN.
|
|
nscoord GetBaselineOffsetFromCrossStart() const {
|
|
return mBaselineOffsetFromCrossStart;
|
|
}
|
|
|
|
// Runs the "resolve the flexible lengths" algorithm, distributing
|
|
// |aFlexContainerMainSize| among the |aItems| and freezing them.
|
|
void ResolveFlexibleLengths(nscoord aFlexContainerMainSize);
|
|
|
|
void PositionItemsInMainAxis(uint8_t aJustifyContent,
|
|
nscoord aContentBoxMainSize,
|
|
const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
void PositionItemsInCrossAxis(nscoord aLineStartPosition,
|
|
const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
nsTArray<FlexItem> mItems; // Array of the flex items in this flex line.
|
|
|
|
private:
|
|
nscoord mTotalInnerHypotheticalMainSize;
|
|
nscoord mTotalOuterHypotheticalMainSize;
|
|
nscoord mLineCrossSize;
|
|
nscoord mBaselineOffsetFromCrossStart;
|
|
};
|
|
|
|
// Helper-function to find the first non-anonymous-box descendent of aFrame.
|
|
static nsIFrame*
|
|
GetFirstNonAnonBoxDescendant(nsIFrame* aFrame)
|
|
{
|
|
while (aFrame) {
|
|
nsIAtom* pseudoTag = aFrame->StyleContext()->GetPseudo();
|
|
|
|
// If aFrame isn't an anonymous container, then it'll do.
|
|
if (!pseudoTag || // No pseudotag.
|
|
!nsCSSAnonBoxes::IsAnonBox(pseudoTag) || // Pseudotag isn't anon.
|
|
pseudoTag == nsCSSAnonBoxes::mozNonElement) { // Text, not a container.
|
|
break;
|
|
}
|
|
|
|
// Otherwise, descend to its first child and repeat.
|
|
|
|
// SPECIAL CASE: if we're dealing with an anonymous table, then it might
|
|
// be wrapping something non-anonymous in its caption or col-group lists
|
|
// (instead of its principal child list), so we have to look there.
|
|
// (Note: For anonymous tables that have a non-anon cell *and* a non-anon
|
|
// column, we'll always return the column. This is fine; we're really just
|
|
// looking for a handle to *anything* with a meaningful content node inside
|
|
// the table, for use in DOM comparisons to things outside of the table.)
|
|
if (MOZ_UNLIKELY(aFrame->GetType() == nsGkAtoms::tableOuterFrame)) {
|
|
nsIFrame* captionDescendant =
|
|
GetFirstNonAnonBoxDescendant(aFrame->GetFirstChild(kCaptionList));
|
|
if (captionDescendant) {
|
|
return captionDescendant;
|
|
}
|
|
} else if (MOZ_UNLIKELY(aFrame->GetType() == nsGkAtoms::tableFrame)) {
|
|
nsIFrame* colgroupDescendant =
|
|
GetFirstNonAnonBoxDescendant(aFrame->GetFirstChild(kColGroupList));
|
|
if (colgroupDescendant) {
|
|
return colgroupDescendant;
|
|
}
|
|
}
|
|
|
|
// USUAL CASE: Descend to the first child in principal list.
|
|
aFrame = aFrame->GetFirstPrincipalChild();
|
|
}
|
|
return aFrame;
|
|
}
|
|
|
|
/**
|
|
* Sorting helper-function that compares two frames' "order" property-values,
|
|
* and if they're equal, compares the DOM positions of their corresponding
|
|
* content nodes. Returns true if aFrame1 is "less than or equal to" aFrame2
|
|
* according to this comparison.
|
|
*
|
|
* Note: This can't be a static function, because we need to pass it as a
|
|
* template argument. (Only functions with external linkage can be passed as
|
|
* template arguments.)
|
|
*
|
|
* @return true if the computed "order" property of aFrame1 is less than that
|
|
* of aFrame2, or if the computed "order" values are equal and aFrame1's
|
|
* corresponding DOM node is earlier than aFrame2's in the DOM tree.
|
|
* Otherwise, returns false.
|
|
*/
|
|
bool
|
|
IsOrderLEQWithDOMFallback(nsIFrame* aFrame1,
|
|
nsIFrame* aFrame2)
|
|
{
|
|
MOZ_ASSERT(aFrame1->IsFlexItem() && aFrame2->IsFlexItem(),
|
|
"this method only intended for comparing flex items");
|
|
|
|
if (aFrame1 == aFrame2) {
|
|
// Anything is trivially LEQ itself, so we return "true" here... but it's
|
|
// probably bad if we end up actually needing this, so let's assert.
|
|
NS_ERROR("Why are we checking if a frame is LEQ itself?");
|
|
return true;
|
|
}
|
|
|
|
// If we've got a placeholder frame, use its out-of-flow frame's 'order' val.
|
|
{
|
|
nsIFrame* aRealFrame1 = nsPlaceholderFrame::GetRealFrameFor(aFrame1);
|
|
nsIFrame* aRealFrame2 = nsPlaceholderFrame::GetRealFrameFor(aFrame2);
|
|
|
|
int32_t order1 = aRealFrame1->StylePosition()->mOrder;
|
|
int32_t order2 = aRealFrame2->StylePosition()->mOrder;
|
|
|
|
if (order1 != order2) {
|
|
return order1 < order2;
|
|
}
|
|
}
|
|
|
|
// The "order" values are equal, so we need to fall back on DOM comparison.
|
|
// For that, we need to dig through any anonymous box wrapper frames to find
|
|
// the actual frame that corresponds to our child content.
|
|
aFrame1 = GetFirstNonAnonBoxDescendant(aFrame1);
|
|
aFrame2 = GetFirstNonAnonBoxDescendant(aFrame2);
|
|
MOZ_ASSERT(aFrame1 && aFrame2,
|
|
"why do we have an anonymous box without any "
|
|
"non-anonymous descendants?");
|
|
|
|
|
|
// Special case:
|
|
// If either frame is for generated content from ::before or ::after, then
|
|
// we can't use nsContentUtils::PositionIsBefore(), since that method won't
|
|
// recognize generated content as being an actual sibling of other nodes.
|
|
// We know where ::before and ::after nodes *effectively* insert in the DOM
|
|
// tree, though (at the beginning & end), so we can just special-case them.
|
|
nsIAtom* pseudo1 = aFrame1->StyleContext()->GetPseudo();
|
|
nsIAtom* pseudo2 = aFrame2->StyleContext()->GetPseudo();
|
|
if (pseudo1 == nsCSSPseudoElements::before ||
|
|
pseudo2 == nsCSSPseudoElements::after) {
|
|
// frame1 is ::before and/or frame2 is ::after => frame1 is LEQ frame2.
|
|
return true;
|
|
}
|
|
if (pseudo1 == nsCSSPseudoElements::after ||
|
|
pseudo2 == nsCSSPseudoElements::before) {
|
|
// frame1 is ::after and/or frame2 is ::before => frame1 is not LEQ frame2.
|
|
return false;
|
|
}
|
|
|
|
// Usual case: Compare DOM position.
|
|
nsIContent* content1 = aFrame1->GetContent();
|
|
nsIContent* content2 = aFrame2->GetContent();
|
|
MOZ_ASSERT(content1 != content2,
|
|
"Two different flex items are using the same nsIContent node for "
|
|
"comparison, so we may be sorting them in an arbitrary order");
|
|
|
|
return nsContentUtils::PositionIsBefore(content1, content2);
|
|
}
|
|
|
|
/**
|
|
* Sorting helper-function that compares two frames' "order" property-values.
|
|
* Returns true if aFrame1 is "less than or equal to" aFrame2 according to this
|
|
* comparison.
|
|
*
|
|
* Note: This can't be a static function, because we need to pass it as a
|
|
* template argument. (Only functions with external linkage can be passed as
|
|
* template arguments.)
|
|
*
|
|
* @return true if the computed "order" property of aFrame1 is less than or
|
|
* equal to that of aFrame2. Otherwise, returns false.
|
|
*/
|
|
bool
|
|
IsOrderLEQ(nsIFrame* aFrame1,
|
|
nsIFrame* aFrame2)
|
|
{
|
|
MOZ_ASSERT(aFrame1->IsFlexItem() && aFrame2->IsFlexItem(),
|
|
"this method only intended for comparing flex items");
|
|
|
|
// If we've got a placeholder frame, use its out-of-flow frame's 'order' val.
|
|
nsIFrame* aRealFrame1 = nsPlaceholderFrame::GetRealFrameFor(aFrame1);
|
|
nsIFrame* aRealFrame2 = nsPlaceholderFrame::GetRealFrameFor(aFrame2);
|
|
|
|
int32_t order1 = aRealFrame1->StylePosition()->mOrder;
|
|
int32_t order2 = aRealFrame2->StylePosition()->mOrder;
|
|
|
|
return order1 <= order2;
|
|
}
|
|
|
|
bool
|
|
nsFlexContainerFrame::IsHorizontal()
|
|
{
|
|
const FlexboxAxisTracker axisTracker(this);
|
|
return IsAxisHorizontal(axisTracker.GetMainAxis());
|
|
}
|
|
|
|
FlexItem
|
|
nsFlexContainerFrame::GenerateFlexItemForChild(
|
|
nsPresContext* aPresContext,
|
|
nsIFrame* aChildFrame,
|
|
const nsHTMLReflowState& aParentReflowState,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
// Create temporary reflow state just for sizing -- to get hypothetical
|
|
// main-size and the computed values of min / max main-size property.
|
|
// (This reflow state will _not_ be used for reflow.)
|
|
nsHTMLReflowState childRS(aPresContext, aParentReflowState, aChildFrame,
|
|
nsSize(aParentReflowState.ComputedWidth(),
|
|
aParentReflowState.ComputedHeight()));
|
|
|
|
// FLEX GROW & SHRINK WEIGHTS
|
|
// --------------------------
|
|
const nsStylePosition* stylePos = aChildFrame->StylePosition();
|
|
float flexGrow = stylePos->mFlexGrow;
|
|
float flexShrink = stylePos->mFlexShrink;
|
|
|
|
// MAIN SIZES (flex base size, min/max size)
|
|
// -----------------------------------------
|
|
nscoord flexBaseSize = GET_MAIN_COMPONENT(aAxisTracker,
|
|
childRS.ComputedWidth(),
|
|
childRS.ComputedHeight());
|
|
nscoord mainMinSize = GET_MAIN_COMPONENT(aAxisTracker,
|
|
childRS.ComputedMinWidth(),
|
|
childRS.ComputedMinHeight());
|
|
nscoord mainMaxSize = GET_MAIN_COMPONENT(aAxisTracker,
|
|
childRS.ComputedMaxWidth(),
|
|
childRS.ComputedMaxHeight());
|
|
// This is enforced by the nsHTMLReflowState where these values come from:
|
|
MOZ_ASSERT(mainMinSize <= mainMaxSize, "min size is larger than max size");
|
|
|
|
// CROSS MIN/MAX SIZE
|
|
// ------------------
|
|
|
|
nscoord crossMinSize = GET_CROSS_COMPONENT(aAxisTracker,
|
|
childRS.ComputedMinWidth(),
|
|
childRS.ComputedMinHeight());
|
|
nscoord crossMaxSize = GET_CROSS_COMPONENT(aAxisTracker,
|
|
childRS.ComputedMaxWidth(),
|
|
childRS.ComputedMaxHeight());
|
|
|
|
// SPECIAL-CASE FOR WIDGET-IMPOSED SIZES
|
|
// Check if we're a themed widget, in which case we might have a minimum
|
|
// main & cross size imposed by our widget (which we can't go below), or
|
|
// (more severe) our widget might have only a single valid size.
|
|
bool isFixedSizeWidget = false;
|
|
const nsStyleDisplay* disp = aChildFrame->StyleDisplay();
|
|
if (aChildFrame->IsThemed(disp)) {
|
|
nsIntSize widgetMinSize(0, 0);
|
|
bool canOverride = true;
|
|
aPresContext->GetTheme()->
|
|
GetMinimumWidgetSize(childRS.rendContext, aChildFrame,
|
|
disp->mAppearance,
|
|
&widgetMinSize, &canOverride);
|
|
|
|
nscoord widgetMainMinSize =
|
|
aPresContext->DevPixelsToAppUnits(
|
|
aAxisTracker.GetMainComponent(widgetMinSize));
|
|
nscoord widgetCrossMinSize =
|
|
aPresContext->DevPixelsToAppUnits(
|
|
aAxisTracker.GetCrossComponent(widgetMinSize));
|
|
|
|
// GMWS() returns border-box. We need content-box, so subtract
|
|
// borderPadding (but don't let that push our min sizes below 0).
|
|
nsMargin& bp = childRS.ComputedPhysicalBorderPadding();
|
|
widgetMainMinSize = std::max(widgetMainMinSize -
|
|
aAxisTracker.GetMarginSizeInMainAxis(bp), 0);
|
|
widgetCrossMinSize = std::max(widgetCrossMinSize -
|
|
aAxisTracker.GetMarginSizeInCrossAxis(bp), 0);
|
|
|
|
if (!canOverride) {
|
|
// Fixed-size widget: freeze our main-size at the widget's mandated size.
|
|
// (Set min and max main-sizes to that size, too, to keep us from
|
|
// clamping to any other size later on.)
|
|
flexBaseSize = mainMinSize = mainMaxSize = widgetMainMinSize;
|
|
crossMinSize = crossMaxSize = widgetCrossMinSize;
|
|
isFixedSizeWidget = true;
|
|
} else {
|
|
// Variable-size widget: ensure our min/max sizes are at least as large
|
|
// as the widget's mandated minimum size, so we don't flex below that.
|
|
mainMinSize = std::max(mainMinSize, widgetMainMinSize);
|
|
mainMaxSize = std::max(mainMaxSize, widgetMainMinSize);
|
|
|
|
crossMinSize = std::max(crossMinSize, widgetCrossMinSize);
|
|
crossMaxSize = std::max(crossMaxSize, widgetCrossMinSize);
|
|
}
|
|
}
|
|
|
|
// Construct the flex item!
|
|
FlexItem item(aChildFrame,
|
|
flexGrow, flexShrink, flexBaseSize,
|
|
mainMinSize, mainMaxSize,
|
|
crossMinSize, crossMaxSize,
|
|
childRS.ComputedPhysicalMargin(),
|
|
childRS.ComputedPhysicalBorderPadding(),
|
|
aAxisTracker);
|
|
|
|
// If we're inflexible, we can just freeze to our hypothetical main-size
|
|
// up-front. Similarly, if we're a fixed-size widget, we only have one
|
|
// valid size, so we freeze to keep ourselves from flexing.
|
|
if (isFixedSizeWidget || (flexGrow == 0.0f && flexShrink == 0.0f)) {
|
|
item.Freeze();
|
|
}
|
|
|
|
return item;
|
|
}
|
|
|
|
nsresult
|
|
nsFlexContainerFrame::
|
|
ResolveFlexItemMaxContentSizing(nsPresContext* aPresContext,
|
|
FlexItem& aFlexItem,
|
|
const nsHTMLReflowState& aParentReflowState,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
if (IsAxisHorizontal(aAxisTracker.GetMainAxis())) {
|
|
// Nothing to do -- this function is only for measuring flex items
|
|
// in a vertical flex container.
|
|
return NS_OK;
|
|
}
|
|
|
|
if (NS_AUTOHEIGHT != aFlexItem.GetFlexBaseSize()) {
|
|
// Nothing to do; this function's only relevant for flex items
|
|
// with a base size of "auto" (or equivalent).
|
|
// XXXdholbert If & when we handle "min-height: min-content" for flex items,
|
|
// we'll want to resolve that in this function, too.
|
|
return NS_OK;
|
|
}
|
|
|
|
// If we get here, we're vertical and our main size ended up being
|
|
// unconstrained. We need to use our "max-content" height, which is what we
|
|
// get from reflowing into our available width.
|
|
// Note: This has to come *after* we construct the FlexItem, since we
|
|
// invoke at least one convenience method (ResolveStretchedCrossSize) which
|
|
// requires a FlexItem.
|
|
|
|
// Give the item a special reflow with "mIsFlexContainerMeasuringHeight"
|
|
// set. This tells it to behave as if it had "height: auto", regardless
|
|
// of what the "height" property is actually set to.
|
|
nsHTMLReflowState
|
|
childRSForMeasuringHeight(aPresContext, aParentReflowState,
|
|
aFlexItem.Frame(),
|
|
nsSize(aParentReflowState.ComputedWidth(),
|
|
NS_UNCONSTRAINEDSIZE),
|
|
-1, -1, nsHTMLReflowState::CALLER_WILL_INIT);
|
|
childRSForMeasuringHeight.mFlags.mIsFlexContainerMeasuringHeight = true;
|
|
childRSForMeasuringHeight.Init(aPresContext);
|
|
|
|
aFlexItem.ResolveStretchedCrossSize(aParentReflowState.ComputedWidth(),
|
|
aAxisTracker);
|
|
if (aFlexItem.IsStretched()) {
|
|
childRSForMeasuringHeight.SetComputedWidth(aFlexItem.GetCrossSize());
|
|
childRSForMeasuringHeight.mFlags.mHResize = true;
|
|
}
|
|
|
|
// If this item is flexible (vertically), then we assume that the
|
|
// computed-height we're reflowing with now could be different
|
|
// from the one we'll use for this flex item's "actual" reflow later on.
|
|
// In that case, we need to be sure the flex item treats this as a
|
|
// vertical resize, even though none of its ancestors are necessarily
|
|
// being vertically resized.
|
|
// (Note: We don't have to do this for width, because InitResizeFlags
|
|
// will always turn on mHResize on when it sees that the computed width
|
|
// is different from current width, and that's all we need.)
|
|
if (!aFlexItem.IsFrozen()) { // Are we flexible?
|
|
childRSForMeasuringHeight.mFlags.mVResize = true;
|
|
}
|
|
|
|
nsHTMLReflowMetrics childDesiredSize(childRSForMeasuringHeight.GetWritingMode());
|
|
nsReflowStatus childReflowStatus;
|
|
const uint32_t flags = NS_FRAME_NO_MOVE_FRAME;
|
|
nsresult rv = ReflowChild(aFlexItem.Frame(), aPresContext,
|
|
childDesiredSize, childRSForMeasuringHeight,
|
|
0, 0, flags, childReflowStatus);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
MOZ_ASSERT(NS_FRAME_IS_COMPLETE(childReflowStatus),
|
|
"We gave flex item unconstrained available height, so it "
|
|
"should be complete");
|
|
|
|
rv = FinishReflowChild(aFlexItem.Frame(), aPresContext,
|
|
&childRSForMeasuringHeight, childDesiredSize,
|
|
0, 0, flags);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
// Subtract border/padding in vertical axis, to get _just_
|
|
// the effective computed value of the "height" property.
|
|
nscoord childDesiredHeight = childDesiredSize.Height() -
|
|
childRSForMeasuringHeight.ComputedPhysicalBorderPadding().TopBottom();
|
|
childDesiredHeight = std::max(0, childDesiredHeight);
|
|
|
|
aFlexItem.SetFlexBaseSizeAndMainSize(childDesiredHeight);
|
|
aFlexItem.SetHadMeasuringReflow();
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
FlexItem::FlexItem(nsIFrame* aChildFrame,
|
|
float aFlexGrow, float aFlexShrink, nscoord aFlexBaseSize,
|
|
nscoord aMainMinSize, nscoord aMainMaxSize,
|
|
nscoord aCrossMinSize, nscoord aCrossMaxSize,
|
|
nsMargin aMargin, nsMargin aBorderPadding,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
: mFrame(aChildFrame),
|
|
mFlexGrow(aFlexGrow),
|
|
mFlexShrink(aFlexShrink),
|
|
mBorderPadding(aBorderPadding),
|
|
mMargin(aMargin),
|
|
mMainMinSize(aMainMinSize),
|
|
mMainMaxSize(aMainMaxSize),
|
|
mCrossMinSize(aCrossMinSize),
|
|
mCrossMaxSize(aCrossMaxSize),
|
|
mMainPosn(0),
|
|
mCrossSize(0),
|
|
mCrossPosn(0),
|
|
mAscent(0),
|
|
mShareOfFlexWeightSoFar(0.0f),
|
|
mIsFrozen(false),
|
|
mHadMinViolation(false),
|
|
mHadMaxViolation(false),
|
|
mHadMeasuringReflow(false),
|
|
mIsStretched(false),
|
|
mAlignSelf(aChildFrame->StylePosition()->mAlignSelf)
|
|
{
|
|
MOZ_ASSERT(aChildFrame, "expecting a non-null child frame");
|
|
|
|
SetFlexBaseSizeAndMainSize(aFlexBaseSize);
|
|
|
|
// Assert that any "auto" margin components are set to 0.
|
|
// (We'll resolve them later; until then, we want to treat them as 0-sized.)
|
|
#ifdef DEBUG
|
|
{
|
|
const nsStyleSides& styleMargin = mFrame->StyleMargin()->mMargin;
|
|
NS_FOR_CSS_SIDES(side) {
|
|
if (styleMargin.GetUnit(side) == eStyleUnit_Auto) {
|
|
MOZ_ASSERT(GetMarginComponentForSide(side) == 0,
|
|
"Someone else tried to resolve our auto margin");
|
|
}
|
|
}
|
|
}
|
|
#endif // DEBUG
|
|
|
|
// Resolve "align-self: auto" to parent's "align-items" value.
|
|
if (mAlignSelf == NS_STYLE_ALIGN_SELF_AUTO) {
|
|
mAlignSelf =
|
|
mFrame->StyleContext()->GetParent()->StylePosition()->mAlignItems;
|
|
}
|
|
|
|
// If the flex item's inline axis is the same as the cross axis, then
|
|
// 'align-self:baseline' is identical to 'flex-start'. If that's the case, we
|
|
// just directly convert our align-self value here, so that we don't have to
|
|
// handle this with special cases elsewhere.
|
|
// Moreover: for the time being (until we support writing-modes),
|
|
// all inline axes are horizontal -- so we can just check if the cross axis
|
|
// is horizontal.
|
|
// FIXME: Once we support writing-mode (vertical text), this IsAxisHorizontal
|
|
// check won't be sufficient anymore -- we'll actually need to compare our
|
|
// inline axis vs. the cross axis.
|
|
if (mAlignSelf == NS_STYLE_ALIGN_ITEMS_BASELINE &&
|
|
IsAxisHorizontal(aAxisTracker.GetCrossAxis())) {
|
|
mAlignSelf = NS_STYLE_ALIGN_ITEMS_FLEX_START;
|
|
}
|
|
}
|
|
|
|
nscoord
|
|
FlexItem::GetBaselineOffsetFromOuterCrossStart(
|
|
AxisOrientationType aCrossAxis) const
|
|
{
|
|
// NOTE: Currently, 'mAscent' (taken from reflow) is an inherently vertical
|
|
// measurement -- it's the distance from the border-top edge of this FlexItem
|
|
// to its baseline. So, we can really only do baseline alignment when the
|
|
// cross axis is vertical. (The FlexItem constructor enforces this when
|
|
// resolving the item's "mAlignSelf" value).
|
|
MOZ_ASSERT(!IsAxisHorizontal(aCrossAxis),
|
|
"Only expecting to be doing baseline computations when the "
|
|
"cross axis is vertical");
|
|
|
|
nscoord marginTopToBaseline = mAscent + mMargin.top;
|
|
|
|
if (aCrossAxis == eAxis_TB) {
|
|
// Top-to-bottom (normal case): the distance from the cross-start margin-box
|
|
// edge (i.e. the margin-top edge) to the baseline is ascent + margin-top.
|
|
return marginTopToBaseline;
|
|
}
|
|
|
|
// Bottom-to-top: The distance from the cross-start margin-box edge (i.e. the
|
|
// margin-bottom edge) to the baseline is just the margin-box cross size
|
|
// (i.e. outer cross size), minus the distance from margin-top to baseline
|
|
// (already computed above).
|
|
nscoord outerCrossSize = mCrossSize +
|
|
GetMarginBorderPaddingSizeInAxis(aCrossAxis);
|
|
|
|
return outerCrossSize - marginTopToBaseline;
|
|
}
|
|
|
|
uint32_t
|
|
FlexItem::GetNumAutoMarginsInAxis(AxisOrientationType aAxis) const
|
|
{
|
|
uint32_t numAutoMargins = 0;
|
|
const nsStyleSides& styleMargin = mFrame->StyleMargin()->mMargin;
|
|
for (uint32_t i = 0; i < eNumAxisEdges; i++) {
|
|
Side side = kAxisOrientationToSidesMap[aAxis][i];
|
|
if (styleMargin.GetUnit(side) == eStyleUnit_Auto) {
|
|
numAutoMargins++;
|
|
}
|
|
}
|
|
|
|
// Mostly for clarity:
|
|
MOZ_ASSERT(numAutoMargins <= 2,
|
|
"We're just looking at one item along one dimension, so we "
|
|
"should only have examined 2 margins");
|
|
|
|
return numAutoMargins;
|
|
}
|
|
|
|
// Keeps track of our position along a particular axis (where a '0' position
|
|
// corresponds to the 'start' edge of that axis).
|
|
// This class shouldn't be instantiated directly -- rather, it should only be
|
|
// instantiated via its subclasses defined below.
|
|
class MOZ_STACK_CLASS PositionTracker {
|
|
public:
|
|
// Accessor for the current value of the position that we're tracking.
|
|
inline nscoord GetPosition() const { return mPosition; }
|
|
inline AxisOrientationType GetAxis() const { return mAxis; }
|
|
|
|
// Advances our position across the start edge of the given margin, in the
|
|
// axis we're tracking.
|
|
void EnterMargin(const nsMargin& aMargin)
|
|
{
|
|
Side side = kAxisOrientationToSidesMap[mAxis][eAxisEdge_Start];
|
|
mPosition += MarginComponentForSide(aMargin, side);
|
|
}
|
|
|
|
// Advances our position across the end edge of the given margin, in the axis
|
|
// we're tracking.
|
|
void ExitMargin(const nsMargin& aMargin)
|
|
{
|
|
Side side = kAxisOrientationToSidesMap[mAxis][eAxisEdge_End];
|
|
mPosition += MarginComponentForSide(aMargin, side);
|
|
}
|
|
|
|
// Advances our current position from the start side of a child frame's
|
|
// border-box to the frame's upper or left edge (depending on our axis).
|
|
// (Note that this is a no-op if our axis grows in positive direction.)
|
|
void EnterChildFrame(nscoord aChildFrameSize)
|
|
{
|
|
if (!AxisGrowsInPositiveDirection(mAxis))
|
|
mPosition += aChildFrameSize;
|
|
}
|
|
|
|
// Advances our current position from a frame's upper or left border-box edge
|
|
// (whichever is in the axis we're tracking) to the 'end' side of the frame
|
|
// in the axis that we're tracking. (Note that this is a no-op if our axis
|
|
// grows in the negative direction.)
|
|
void ExitChildFrame(nscoord aChildFrameSize)
|
|
{
|
|
if (AxisGrowsInPositiveDirection(mAxis))
|
|
mPosition += aChildFrameSize;
|
|
}
|
|
|
|
protected:
|
|
// Protected constructor, to be sure we're only instantiated via a subclass.
|
|
PositionTracker(AxisOrientationType aAxis)
|
|
: mPosition(0),
|
|
mAxis(aAxis)
|
|
{}
|
|
|
|
private:
|
|
// Private copy-constructor, since we don't want any instances of our
|
|
// subclasses to be accidentally copied.
|
|
PositionTracker(const PositionTracker& aOther)
|
|
: mPosition(aOther.mPosition),
|
|
mAxis(aOther.mAxis)
|
|
{}
|
|
|
|
protected:
|
|
// Member data:
|
|
nscoord mPosition; // The position we're tracking
|
|
const AxisOrientationType mAxis; // The axis along which we're moving
|
|
};
|
|
|
|
// Tracks our position in the main axis, when we're laying out flex items.
|
|
// The "0" position represents the main-start edge of the flex container's
|
|
// content-box.
|
|
class MOZ_STACK_CLASS MainAxisPositionTracker : public PositionTracker {
|
|
public:
|
|
MainAxisPositionTracker(const FlexboxAxisTracker& aAxisTracker,
|
|
const nsTArray<FlexItem>& aItems,
|
|
uint8_t aJustifyContent,
|
|
nscoord aContentBoxMainSize);
|
|
|
|
~MainAxisPositionTracker() {
|
|
MOZ_ASSERT(mNumPackingSpacesRemaining == 0,
|
|
"miscounted the number of packing spaces");
|
|
MOZ_ASSERT(mNumAutoMarginsInMainAxis == 0,
|
|
"miscounted the number of auto margins");
|
|
}
|
|
|
|
// Advances past the packing space (if any) between two flex items
|
|
void TraversePackingSpace();
|
|
|
|
// If aItem has any 'auto' margins in the main axis, this method updates the
|
|
// corresponding values in its margin.
|
|
void ResolveAutoMarginsInMainAxis(FlexItem& aItem);
|
|
|
|
private:
|
|
nscoord mPackingSpaceRemaining;
|
|
uint32_t mNumAutoMarginsInMainAxis;
|
|
uint32_t mNumPackingSpacesRemaining;
|
|
uint8_t mJustifyContent;
|
|
};
|
|
|
|
// Utility class for managing our position along the cross axis along
|
|
// the whole flex container (at a higher level than a single line).
|
|
// The "0" position represents the cross-start edge of the flex container's
|
|
// content-box.
|
|
class MOZ_STACK_CLASS CrossAxisPositionTracker : public PositionTracker {
|
|
public:
|
|
CrossAxisPositionTracker(nsTArray<FlexLine>& aLines,
|
|
uint8_t aAlignContent,
|
|
nscoord aContentBoxCrossSize,
|
|
bool aIsCrossSizeDefinite,
|
|
const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
// Advances past the packing space (if any) between two flex lines
|
|
void TraversePackingSpace();
|
|
|
|
// Advances past the given FlexLine
|
|
void TraverseLine(FlexLine& aLine) { mPosition += aLine.GetLineCrossSize(); }
|
|
|
|
private:
|
|
// Redeclare the frame-related methods from PositionTracker as private with
|
|
// MOZ_DELETE, to be sure (at compile time) that no client code can invoke
|
|
// them. (Unlike the other PositionTracker derived classes, this class here
|
|
// deals with FlexLines, not with individual FlexItems or frames.)
|
|
void EnterMargin(const nsMargin& aMargin) MOZ_DELETE;
|
|
void ExitMargin(const nsMargin& aMargin) MOZ_DELETE;
|
|
void EnterChildFrame(nscoord aChildFrameSize) MOZ_DELETE;
|
|
void ExitChildFrame(nscoord aChildFrameSize) MOZ_DELETE;
|
|
|
|
nscoord mPackingSpaceRemaining;
|
|
uint32_t mNumPackingSpacesRemaining;
|
|
uint8_t mAlignContent;
|
|
};
|
|
|
|
// Utility class for managing our position along the cross axis, *within* a
|
|
// single flex line.
|
|
class MOZ_STACK_CLASS SingleLineCrossAxisPositionTracker : public PositionTracker {
|
|
public:
|
|
SingleLineCrossAxisPositionTracker(const FlexboxAxisTracker& aAxisTracker);
|
|
|
|
void ResolveAutoMarginsInCrossAxis(const FlexLine& aLine,
|
|
FlexItem& aItem);
|
|
|
|
void EnterAlignPackingSpace(const FlexLine& aLine,
|
|
const FlexItem& aItem);
|
|
|
|
// Resets our position to the cross-start edge of this line.
|
|
inline void ResetPosition() { mPosition = 0; }
|
|
};
|
|
|
|
//----------------------------------------------------------------------
|
|
|
|
// Frame class boilerplate
|
|
// =======================
|
|
|
|
NS_QUERYFRAME_HEAD(nsFlexContainerFrame)
|
|
NS_QUERYFRAME_ENTRY(nsFlexContainerFrame)
|
|
NS_QUERYFRAME_TAIL_INHERITING(nsFlexContainerFrameSuper)
|
|
|
|
NS_IMPL_FRAMEARENA_HELPERS(nsFlexContainerFrame)
|
|
|
|
nsIFrame*
|
|
NS_NewFlexContainerFrame(nsIPresShell* aPresShell,
|
|
nsStyleContext* aContext)
|
|
{
|
|
return new (aPresShell) nsFlexContainerFrame(aContext);
|
|
}
|
|
|
|
//----------------------------------------------------------------------
|
|
|
|
// nsFlexContainerFrame Method Implementations
|
|
// ===========================================
|
|
|
|
/* virtual */
|
|
nsFlexContainerFrame::~nsFlexContainerFrame()
|
|
{
|
|
}
|
|
|
|
template<bool IsLessThanOrEqual(nsIFrame*, nsIFrame*)>
|
|
/* static */ bool
|
|
nsFlexContainerFrame::SortChildrenIfNeeded()
|
|
{
|
|
if (nsIFrame::IsFrameListSorted<IsLessThanOrEqual>(mFrames)) {
|
|
return false;
|
|
}
|
|
|
|
nsIFrame::SortFrameList<IsLessThanOrEqual>(mFrames);
|
|
return true;
|
|
}
|
|
|
|
/* virtual */
|
|
nsIAtom*
|
|
nsFlexContainerFrame::GetType() const
|
|
{
|
|
return nsGkAtoms::flexContainerFrame;
|
|
}
|
|
|
|
#ifdef DEBUG_FRAME_DUMP
|
|
NS_IMETHODIMP
|
|
nsFlexContainerFrame::GetFrameName(nsAString& aResult) const
|
|
{
|
|
return MakeFrameName(NS_LITERAL_STRING("FlexContainer"), aResult);
|
|
}
|
|
#endif
|
|
|
|
// Helper for BuildDisplayList, to implement this special-case for flex items
|
|
// from the spec:
|
|
// Flex items paint exactly the same as block-level elements in the
|
|
// normal flow, except that 'z-index' values other than 'auto' create
|
|
// a stacking context even if 'position' is 'static'.
|
|
// http://www.w3.org/TR/2012/CR-css3-flexbox-20120918/#painting
|
|
uint32_t
|
|
GetDisplayFlagsForFlexItem(nsIFrame* aFrame)
|
|
{
|
|
MOZ_ASSERT(aFrame->IsFlexItem(), "Should only be called on flex items");
|
|
|
|
const nsStylePosition* pos = aFrame->StylePosition();
|
|
if (pos->mZIndex.GetUnit() == eStyleUnit_Integer) {
|
|
return nsIFrame::DISPLAY_CHILD_FORCE_STACKING_CONTEXT;
|
|
}
|
|
return nsIFrame::DISPLAY_CHILD_FORCE_PSEUDO_STACKING_CONTEXT;
|
|
}
|
|
|
|
void
|
|
nsFlexContainerFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
|
|
const nsRect& aDirtyRect,
|
|
const nsDisplayListSet& aLists)
|
|
{
|
|
NS_ASSERTION(
|
|
nsIFrame::IsFrameListSorted<IsOrderLEQWithDOMFallback>(mFrames),
|
|
"Child frames aren't sorted correctly");
|
|
|
|
DisplayBorderBackgroundOutline(aBuilder, aLists);
|
|
|
|
// Our children are all block-level, so their borders/backgrounds all go on
|
|
// the BlockBorderBackgrounds list.
|
|
nsDisplayListSet childLists(aLists, aLists.BlockBorderBackgrounds());
|
|
for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
|
|
BuildDisplayListForChild(aBuilder, e.get(), aDirtyRect, childLists,
|
|
GetDisplayFlagsForFlexItem(e.get()));
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
// helper for the debugging method below
|
|
bool
|
|
FrameWantsToBeInAnonymousFlexItem(nsIFrame* aFrame)
|
|
{
|
|
// Note: This needs to match the logic in
|
|
// nsCSSFrameConstructor::FrameConstructionItem::NeedsAnonFlexItem()
|
|
return (aFrame->IsFrameOfType(nsIFrame::eLineParticipant) ||
|
|
nsGkAtoms::placeholderFrame == aFrame->GetType());
|
|
}
|
|
|
|
// Debugging method, to let us assert that our anonymous flex items are
|
|
// set up correctly -- in particular, we assert:
|
|
// (1) we don't have any inline non-replaced children
|
|
// (2) we don't have any consecutive anonymous flex items
|
|
// (3) we don't have any empty anonymous flex items
|
|
//
|
|
// XXXdholbert This matches what nsCSSFrameConstructor currently does, and what
|
|
// the spec used to say. However, the spec has now changed regarding what
|
|
// types of content get wrapped in an anonymous flexbox item. The patch that
|
|
// implements those changes (in nsCSSFrameConstructor) will need to change
|
|
// this method as well.
|
|
void
|
|
nsFlexContainerFrame::SanityCheckAnonymousFlexItems() const
|
|
{
|
|
bool prevChildWasAnonFlexItem = false;
|
|
for (nsIFrame* child = mFrames.FirstChild(); child;
|
|
child = child->GetNextSibling()) {
|
|
MOZ_ASSERT(!FrameWantsToBeInAnonymousFlexItem(child),
|
|
"frame wants to be inside an anonymous flex item, "
|
|
"but it isn't");
|
|
if (child->StyleContext()->GetPseudo() ==
|
|
nsCSSAnonBoxes::anonymousFlexItem) {
|
|
MOZ_ASSERT(!prevChildWasAnonFlexItem || mChildrenHaveBeenReordered,
|
|
"two anon flex items in a row (shouldn't happen, unless our "
|
|
"children have been reordered with the 'order' property)");
|
|
|
|
nsIFrame* firstWrappedChild = child->GetFirstPrincipalChild();
|
|
MOZ_ASSERT(firstWrappedChild,
|
|
"anonymous flex item is empty (shouldn't happen)");
|
|
prevChildWasAnonFlexItem = true;
|
|
} else {
|
|
prevChildWasAnonFlexItem = false;
|
|
}
|
|
}
|
|
}
|
|
#endif // DEBUG
|
|
|
|
// Based on the sign of aTotalViolation, this function freezes a subset of our
|
|
// flexible sizes, and restores the remaining ones to their initial pref sizes.
|
|
static void
|
|
FreezeOrRestoreEachFlexibleSize(
|
|
const nscoord aTotalViolation,
|
|
nsTArray<FlexItem>& aItems,
|
|
bool aFinalIteration)
|
|
{
|
|
enum FreezeType {
|
|
eFreezeEverything,
|
|
eFreezeMinViolations,
|
|
eFreezeMaxViolations
|
|
};
|
|
|
|
FreezeType freezeType;
|
|
if (aTotalViolation == 0) {
|
|
freezeType = eFreezeEverything;
|
|
} else if (aTotalViolation > 0) {
|
|
freezeType = eFreezeMinViolations;
|
|
} else { // aTotalViolation < 0
|
|
freezeType = eFreezeMaxViolations;
|
|
}
|
|
|
|
for (uint32_t i = 0; i < aItems.Length(); i++) {
|
|
FlexItem& item = aItems[i];
|
|
MOZ_ASSERT(!item.HadMinViolation() || !item.HadMaxViolation(),
|
|
"Can have either min or max violation, but not both");
|
|
|
|
if (!item.IsFrozen()) {
|
|
if (eFreezeEverything == freezeType ||
|
|
(eFreezeMinViolations == freezeType && item.HadMinViolation()) ||
|
|
(eFreezeMaxViolations == freezeType && item.HadMaxViolation())) {
|
|
|
|
MOZ_ASSERT(item.GetMainSize() >= item.GetMainMinSize(),
|
|
"Freezing item at a size below its minimum");
|
|
MOZ_ASSERT(item.GetMainSize() <= item.GetMainMaxSize(),
|
|
"Freezing item at a size above its maximum");
|
|
|
|
item.Freeze();
|
|
} else if (MOZ_UNLIKELY(aFinalIteration)) {
|
|
// XXXdholbert If & when bug 765861 is fixed, we should upgrade this
|
|
// assertion to be fatal except in documents with enormous lengths.
|
|
NS_ERROR("Final iteration still has unfrozen items, this shouldn't"
|
|
" happen unless there was nscoord under/overflow.");
|
|
item.Freeze();
|
|
} // else, we'll reset this item's main size to its flex base size on the
|
|
// next iteration of this algorithm.
|
|
|
|
// Clear this item's violation(s), now that we've dealt with them
|
|
item.ClearViolationFlags();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Implementation of flexbox spec's "resolve the flexible lengths" algorithm.
|
|
// NOTE: aTotalFreeSpace should already have the flex items' margin, border,
|
|
// & padding values subtracted out, so that all we need to do is distribute the
|
|
// remaining free space among content-box sizes. (The spec deals with
|
|
// margin-box sizes, but we can have fewer values in play & a simpler algorithm
|
|
// if we subtract margin/border/padding up front.)
|
|
void
|
|
FlexLine::ResolveFlexibleLengths(nscoord aFlexContainerMainSize)
|
|
{
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG, ("ResolveFlexibleLengths\n"));
|
|
if (mItems.IsEmpty()) {
|
|
return;
|
|
}
|
|
|
|
// Subtract space occupied by our items' margins/borders/padding, so we can
|
|
// just be dealing with the space available for our flex items' content
|
|
// boxes.
|
|
nscoord spaceReservedForMarginBorderPadding =
|
|
mTotalOuterHypotheticalMainSize - mTotalInnerHypotheticalMainSize;
|
|
|
|
nscoord spaceAvailableForFlexItemsContentBoxes =
|
|
aFlexContainerMainSize - spaceReservedForMarginBorderPadding;
|
|
|
|
// Determine whether we're going to be growing or shrinking items.
|
|
const bool isUsingFlexGrow =
|
|
(mTotalOuterHypotheticalMainSize < aFlexContainerMainSize);
|
|
|
|
// NOTE: I claim that this chunk of the algorithm (the looping part) needs to
|
|
// run the loop at MOST aItems.Length() times. This claim should hold up
|
|
// because we'll freeze at least one item on each loop iteration, and once
|
|
// we've run out of items to freeze, there's nothing left to do. However,
|
|
// in most cases, we'll break out of this loop long before we hit that many
|
|
// iterations.
|
|
for (uint32_t iterationCounter = 0;
|
|
iterationCounter < mItems.Length(); iterationCounter++) {
|
|
// Set every not-yet-frozen item's used main size to its
|
|
// flex base size, and subtract all the used main sizes from our
|
|
// total amount of space to determine the 'available free space'
|
|
// (positive or negative) to be distributed among our flexible items.
|
|
nscoord availableFreeSpace = spaceAvailableForFlexItemsContentBoxes;
|
|
for (uint32_t i = 0; i < mItems.Length(); i++) {
|
|
FlexItem& item = mItems[i];
|
|
if (!item.IsFrozen()) {
|
|
item.SetMainSize(item.GetFlexBaseSize());
|
|
}
|
|
availableFreeSpace -= item.GetMainSize();
|
|
}
|
|
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
(" available free space = %d\n", availableFreeSpace));
|
|
|
|
// If sign of free space matches the type of flexing that we're doing, give
|
|
// each flexible item a portion of availableFreeSpace.
|
|
if ((availableFreeSpace > 0 && isUsingFlexGrow) ||
|
|
(availableFreeSpace < 0 && !isUsingFlexGrow)) {
|
|
|
|
// STRATEGY: On each item, we compute & store its "share" of the total
|
|
// flex weight that we've seen so far:
|
|
// curFlexWeight / runningFlexWeightSum
|
|
//
|
|
// Then, when we go to actually distribute the space (in the next loop),
|
|
// we can simply walk backwards through the elements and give each item
|
|
// its "share" multiplied by the remaining available space.
|
|
//
|
|
// SPECIAL CASE: If the sum of the flex weights is larger than the
|
|
// maximum representable float (overflowing to infinity), then we can't
|
|
// sensibly divide out proportional shares anymore. In that case, we
|
|
// simply treat the flex item(s) with the largest flex weights as if
|
|
// their weights were infinite (dwarfing all the others), and we
|
|
// distribute all of the available space among them.
|
|
float runningFlexWeightSum = 0.0f;
|
|
float largestFlexWeight = 0.0f;
|
|
uint32_t numItemsWithLargestFlexWeight = 0;
|
|
for (uint32_t i = 0; i < mItems.Length(); i++) {
|
|
FlexItem& item = mItems[i];
|
|
float curFlexWeight = item.GetFlexWeightToUse(isUsingFlexGrow);
|
|
MOZ_ASSERT(curFlexWeight >= 0.0f, "weights are non-negative");
|
|
|
|
runningFlexWeightSum += curFlexWeight;
|
|
if (NS_finite(runningFlexWeightSum)) {
|
|
if (curFlexWeight == 0.0f) {
|
|
item.SetShareOfFlexWeightSoFar(0.0f);
|
|
} else {
|
|
item.SetShareOfFlexWeightSoFar(curFlexWeight /
|
|
runningFlexWeightSum);
|
|
}
|
|
} // else, the sum of weights overflows to infinity, in which
|
|
// case we don't bother with "SetShareOfFlexWeightSoFar" since
|
|
// we know we won't use it. (instead, we'll just give every
|
|
// item with the largest flex weight an equal share of space.)
|
|
|
|
// Update our largest-flex-weight tracking vars
|
|
if (curFlexWeight > largestFlexWeight) {
|
|
largestFlexWeight = curFlexWeight;
|
|
numItemsWithLargestFlexWeight = 1;
|
|
} else if (curFlexWeight == largestFlexWeight) {
|
|
numItemsWithLargestFlexWeight++;
|
|
}
|
|
}
|
|
|
|
if (runningFlexWeightSum != 0.0f) { // no distribution if no flexibility
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
(" Distributing available space:"));
|
|
for (uint32_t i = mItems.Length() - 1; i < mItems.Length(); --i) {
|
|
FlexItem& item = mItems[i];
|
|
|
|
if (!item.IsFrozen()) {
|
|
// To avoid rounding issues, we compute the change in size for this
|
|
// item, and then subtract it from the remaining available space.
|
|
nscoord sizeDelta = 0;
|
|
if (NS_finite(runningFlexWeightSum)) {
|
|
float myShareOfRemainingSpace =
|
|
item.GetShareOfFlexWeightSoFar();
|
|
|
|
MOZ_ASSERT(myShareOfRemainingSpace >= 0.0f &&
|
|
myShareOfRemainingSpace <= 1.0f,
|
|
"my share should be nonnegative fractional amount");
|
|
|
|
if (myShareOfRemainingSpace == 1.0f) {
|
|
// (We special-case 1.0f to avoid float error from converting
|
|
// availableFreeSpace from integer*1.0f --> float --> integer)
|
|
sizeDelta = availableFreeSpace;
|
|
} else if (myShareOfRemainingSpace > 0.0f) {
|
|
sizeDelta = NSToCoordRound(availableFreeSpace *
|
|
myShareOfRemainingSpace);
|
|
}
|
|
} else if (item.GetFlexWeightToUse(isUsingFlexGrow) ==
|
|
largestFlexWeight) {
|
|
// Total flexibility is infinite, so we're just distributing
|
|
// the available space equally among the items that are tied for
|
|
// having the largest weight (and this is one of those items).
|
|
sizeDelta =
|
|
NSToCoordRound(availableFreeSpace /
|
|
float(numItemsWithLargestFlexWeight));
|
|
numItemsWithLargestFlexWeight--;
|
|
}
|
|
|
|
availableFreeSpace -= sizeDelta;
|
|
|
|
item.SetMainSize(item.GetMainSize() + sizeDelta);
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
(" child %d receives %d, for a total of %d\n",
|
|
i, sizeDelta, item.GetMainSize()));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Fix min/max violations:
|
|
nscoord totalViolation = 0; // keeps track of adjustments for min/max
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
(" Checking for violations:"));
|
|
|
|
for (uint32_t i = 0; i < mItems.Length(); i++) {
|
|
FlexItem& item = mItems[i];
|
|
if (!item.IsFrozen()) {
|
|
if (item.GetMainSize() < item.GetMainMinSize()) {
|
|
// min violation
|
|
totalViolation += item.GetMainMinSize() - item.GetMainSize();
|
|
item.SetMainSize(item.GetMainMinSize());
|
|
item.SetHadMinViolation();
|
|
} else if (item.GetMainSize() > item.GetMainMaxSize()) {
|
|
// max violation
|
|
totalViolation += item.GetMainMaxSize() - item.GetMainSize();
|
|
item.SetMainSize(item.GetMainMaxSize());
|
|
item.SetHadMaxViolation();
|
|
}
|
|
}
|
|
}
|
|
|
|
FreezeOrRestoreEachFlexibleSize(totalViolation, mItems,
|
|
iterationCounter + 1 == mItems.Length());
|
|
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
(" Total violation: %d\n", totalViolation));
|
|
|
|
if (totalViolation == 0) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Post-condition: all lengths should've been frozen.
|
|
#ifdef DEBUG
|
|
for (uint32_t i = 0; i < mItems.Length(); ++i) {
|
|
MOZ_ASSERT(mItems[i].IsFrozen(),
|
|
"All flexible lengths should've been resolved");
|
|
}
|
|
#endif // DEBUG
|
|
}
|
|
|
|
MainAxisPositionTracker::
|
|
MainAxisPositionTracker(const FlexboxAxisTracker& aAxisTracker,
|
|
const nsTArray<FlexItem>& aItems,
|
|
uint8_t aJustifyContent,
|
|
nscoord aContentBoxMainSize)
|
|
: PositionTracker(aAxisTracker.GetMainAxis()),
|
|
mPackingSpaceRemaining(aContentBoxMainSize), // we chip away at this below
|
|
mNumAutoMarginsInMainAxis(0),
|
|
mNumPackingSpacesRemaining(0),
|
|
mJustifyContent(aJustifyContent)
|
|
{
|
|
// mPackingSpaceRemaining is initialized to the container's main size. Now
|
|
// we'll subtract out the main sizes of our flex items, so that it ends up
|
|
// with the *actual* amount of packing space.
|
|
for (uint32_t i = 0; i < aItems.Length(); i++) {
|
|
const FlexItem& curItem = aItems[i];
|
|
nscoord itemMarginBoxMainSize =
|
|
curItem.GetMainSize() +
|
|
curItem.GetMarginBorderPaddingSizeInAxis(aAxisTracker.GetMainAxis());
|
|
mPackingSpaceRemaining -= itemMarginBoxMainSize;
|
|
mNumAutoMarginsInMainAxis += curItem.GetNumAutoMarginsInAxis(mAxis);
|
|
}
|
|
|
|
if (mPackingSpaceRemaining <= 0) {
|
|
// No available packing space to use for resolving auto margins.
|
|
mNumAutoMarginsInMainAxis = 0;
|
|
}
|
|
|
|
// If packing space is negative, 'space-between' behaves like 'flex-start',
|
|
// and 'space-around' behaves like 'center'. In those cases, it's simplest to
|
|
// just pretend we have a different 'justify-content' value and share code.
|
|
if (mPackingSpaceRemaining < 0) {
|
|
if (mJustifyContent == NS_STYLE_JUSTIFY_CONTENT_SPACE_BETWEEN) {
|
|
mJustifyContent = NS_STYLE_JUSTIFY_CONTENT_FLEX_START;
|
|
} else if (mJustifyContent == NS_STYLE_JUSTIFY_CONTENT_SPACE_AROUND) {
|
|
mJustifyContent = NS_STYLE_JUSTIFY_CONTENT_CENTER;
|
|
}
|
|
}
|
|
|
|
// Figure out how much space we'll set aside for auto margins or
|
|
// packing spaces, and advance past any leading packing-space.
|
|
if (mNumAutoMarginsInMainAxis == 0 &&
|
|
mPackingSpaceRemaining != 0 &&
|
|
!aItems.IsEmpty()) {
|
|
switch (mJustifyContent) {
|
|
case NS_STYLE_JUSTIFY_CONTENT_FLEX_START:
|
|
// All packing space should go at the end --> nothing to do here.
|
|
break;
|
|
case NS_STYLE_JUSTIFY_CONTENT_FLEX_END:
|
|
// All packing space goes at the beginning
|
|
mPosition += mPackingSpaceRemaining;
|
|
break;
|
|
case NS_STYLE_JUSTIFY_CONTENT_CENTER:
|
|
// Half the packing space goes at the beginning
|
|
mPosition += mPackingSpaceRemaining / 2;
|
|
break;
|
|
case NS_STYLE_JUSTIFY_CONTENT_SPACE_BETWEEN:
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"negative packing space should make us use 'flex-start' "
|
|
"instead of 'space-between'");
|
|
// 1 packing space between each flex item, no packing space at ends.
|
|
mNumPackingSpacesRemaining = aItems.Length() - 1;
|
|
break;
|
|
case NS_STYLE_JUSTIFY_CONTENT_SPACE_AROUND:
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"negative packing space should make us use 'center' "
|
|
"instead of 'space-around'");
|
|
// 1 packing space between each flex item, plus half a packing space
|
|
// at beginning & end. So our number of full packing-spaces is equal
|
|
// to the number of flex items.
|
|
mNumPackingSpacesRemaining = aItems.Length();
|
|
if (mNumPackingSpacesRemaining > 0) {
|
|
// The edges (start/end) share one full packing space
|
|
nscoord totalEdgePackingSpace =
|
|
mPackingSpaceRemaining / mNumPackingSpacesRemaining;
|
|
|
|
// ...and we'll use half of that right now, at the start
|
|
mPosition += totalEdgePackingSpace / 2;
|
|
// ...but we need to subtract all of it right away, so that we won't
|
|
// hand out any of it to intermediate packing spaces.
|
|
mPackingSpaceRemaining -= totalEdgePackingSpace;
|
|
mNumPackingSpacesRemaining--;
|
|
}
|
|
break;
|
|
default:
|
|
MOZ_CRASH("Unexpected justify-content value");
|
|
}
|
|
}
|
|
|
|
MOZ_ASSERT(mNumPackingSpacesRemaining == 0 ||
|
|
mNumAutoMarginsInMainAxis == 0,
|
|
"extra space should either go to packing space or to "
|
|
"auto margins, but not to both");
|
|
}
|
|
|
|
void
|
|
MainAxisPositionTracker::ResolveAutoMarginsInMainAxis(FlexItem& aItem)
|
|
{
|
|
if (mNumAutoMarginsInMainAxis) {
|
|
const nsStyleSides& styleMargin = aItem.Frame()->StyleMargin()->mMargin;
|
|
for (uint32_t i = 0; i < eNumAxisEdges; i++) {
|
|
Side side = kAxisOrientationToSidesMap[mAxis][i];
|
|
if (styleMargin.GetUnit(side) == eStyleUnit_Auto) {
|
|
// NOTE: This integer math will skew the distribution of remainder
|
|
// app-units towards the end, which is fine.
|
|
nscoord curAutoMarginSize =
|
|
mPackingSpaceRemaining / mNumAutoMarginsInMainAxis;
|
|
|
|
MOZ_ASSERT(aItem.GetMarginComponentForSide(side) == 0,
|
|
"Expecting auto margins to have value '0' before we "
|
|
"resolve them");
|
|
aItem.SetMarginComponentForSide(side, curAutoMarginSize);
|
|
|
|
mNumAutoMarginsInMainAxis--;
|
|
mPackingSpaceRemaining -= curAutoMarginSize;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
MainAxisPositionTracker::TraversePackingSpace()
|
|
{
|
|
if (mNumPackingSpacesRemaining) {
|
|
MOZ_ASSERT(mJustifyContent == NS_STYLE_JUSTIFY_CONTENT_SPACE_BETWEEN ||
|
|
mJustifyContent == NS_STYLE_JUSTIFY_CONTENT_SPACE_AROUND,
|
|
"mNumPackingSpacesRemaining only applies for "
|
|
"space-between/space-around");
|
|
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"ran out of packing space earlier than we expected");
|
|
|
|
// NOTE: This integer math will skew the distribution of remainder
|
|
// app-units towards the end, which is fine.
|
|
nscoord curPackingSpace =
|
|
mPackingSpaceRemaining / mNumPackingSpacesRemaining;
|
|
|
|
mPosition += curPackingSpace;
|
|
mNumPackingSpacesRemaining--;
|
|
mPackingSpaceRemaining -= curPackingSpace;
|
|
}
|
|
}
|
|
|
|
CrossAxisPositionTracker::
|
|
CrossAxisPositionTracker(nsTArray<FlexLine>& aLines,
|
|
uint8_t aAlignContent,
|
|
nscoord aContentBoxCrossSize,
|
|
bool aIsCrossSizeDefinite,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
: PositionTracker(aAxisTracker.GetCrossAxis()),
|
|
mPackingSpaceRemaining(0),
|
|
mNumPackingSpacesRemaining(0),
|
|
mAlignContent(aAlignContent)
|
|
{
|
|
MOZ_ASSERT(!aLines.IsEmpty(), "We should have at least 1 line");
|
|
|
|
if (aIsCrossSizeDefinite && aLines.Length() == 1) {
|
|
// "If the flex container has only a single line (even if it's a
|
|
// multi-line flex container) and has a definite cross size, the cross
|
|
// size of the flex line is the flex container's inner cross size."
|
|
// SOURCE: http://dev.w3.org/csswg/css-flexbox/#algo-line-break
|
|
// NOTE: This means (by definition) that there's no packing space, which
|
|
// means we don't need to be concerned with "align-conent" at all and we
|
|
// can return early. This is handy, because this is the usual case (for
|
|
// single-line flexbox).
|
|
aLines[0].SetLineCrossSize(aContentBoxCrossSize);
|
|
return;
|
|
}
|
|
|
|
// NOTE: The rest of this function should essentially match
|
|
// MainAxisPositionTracker's constructor, though with FlexLines instead of
|
|
// FlexItems, and with the additional value "stretch" (and of course with
|
|
// cross sizes instead of main sizes.)
|
|
|
|
// Figure out how much packing space we have (container's cross size minus
|
|
// all the lines' cross sizes)
|
|
mPackingSpaceRemaining = aContentBoxCrossSize;
|
|
for (uint32_t i = 0; i < aLines.Length(); i++) {
|
|
const FlexLine& line = aLines[i];
|
|
mPackingSpaceRemaining -= line.GetLineCrossSize();
|
|
}
|
|
|
|
// If packing space is negative, 'space-between' and 'stretch' behave like
|
|
// 'flex-start', and 'space-around' behaves like 'center'. In those cases,
|
|
// it's simplest to just pretend we have a different 'align-content' value
|
|
// and share code.
|
|
if (mPackingSpaceRemaining < 0) {
|
|
if (mAlignContent == NS_STYLE_ALIGN_CONTENT_SPACE_BETWEEN ||
|
|
mAlignContent == NS_STYLE_ALIGN_CONTENT_STRETCH) {
|
|
mAlignContent = NS_STYLE_ALIGN_CONTENT_FLEX_START;
|
|
} else if (mAlignContent == NS_STYLE_ALIGN_CONTENT_SPACE_AROUND) {
|
|
mAlignContent = NS_STYLE_ALIGN_CONTENT_CENTER;
|
|
}
|
|
}
|
|
|
|
// Figure out how much space we'll set aside for packing spaces, and advance
|
|
// past any leading packing-space.
|
|
if (mPackingSpaceRemaining != 0) {
|
|
switch (mAlignContent) {
|
|
case NS_STYLE_ALIGN_CONTENT_FLEX_START:
|
|
// All packing space should go at the end --> nothing to do here.
|
|
break;
|
|
case NS_STYLE_ALIGN_CONTENT_FLEX_END:
|
|
// All packing space goes at the beginning
|
|
mPosition += mPackingSpaceRemaining;
|
|
break;
|
|
case NS_STYLE_ALIGN_CONTENT_CENTER:
|
|
// Half the packing space goes at the beginning
|
|
mPosition += mPackingSpaceRemaining / 2;
|
|
break;
|
|
case NS_STYLE_ALIGN_CONTENT_SPACE_BETWEEN:
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"negative packing space should make us use 'flex-start' "
|
|
"instead of 'space-between'");
|
|
// 1 packing space between each flex line, no packing space at ends.
|
|
mNumPackingSpacesRemaining = aLines.Length() - 1;
|
|
break;
|
|
case NS_STYLE_ALIGN_CONTENT_SPACE_AROUND: {
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"negative packing space should make us use 'center' "
|
|
"instead of 'space-around'");
|
|
// 1 packing space between each flex line, plus half a packing space
|
|
// at beginning & end. So our number of full packing-spaces is equal
|
|
// to the number of flex lines.
|
|
mNumPackingSpacesRemaining = aLines.Length();
|
|
// The edges (start/end) share one full packing space
|
|
nscoord totalEdgePackingSpace =
|
|
mPackingSpaceRemaining / mNumPackingSpacesRemaining;
|
|
|
|
// ...and we'll use half of that right now, at the start
|
|
mPosition += totalEdgePackingSpace / 2;
|
|
// ...but we need to subtract all of it right away, so that we won't
|
|
// hand out any of it to intermediate packing spaces.
|
|
mPackingSpaceRemaining -= totalEdgePackingSpace;
|
|
mNumPackingSpacesRemaining--;
|
|
break;
|
|
}
|
|
case NS_STYLE_ALIGN_CONTENT_STRETCH:
|
|
// Split space equally between the lines:
|
|
MOZ_ASSERT(mPackingSpaceRemaining > 0,
|
|
"negative packing space should make us use 'flex-start' "
|
|
"instead of 'stretch' (and we shouldn't bother with this "
|
|
"code if we have 0 packing space)");
|
|
|
|
for (uint32_t i = 0; i < aLines.Length(); i++) {
|
|
FlexLine& line = aLines[i];
|
|
// Our share is the amount of space remaining, divided by the number
|
|
// of lines remainig.
|
|
nscoord shareOfExtraSpace =
|
|
mPackingSpaceRemaining / (aLines.Length() - i);
|
|
nscoord newSize = line.GetLineCrossSize() + shareOfExtraSpace;
|
|
line.SetLineCrossSize(newSize);
|
|
mPackingSpaceRemaining -= shareOfExtraSpace;
|
|
}
|
|
break;
|
|
default:
|
|
MOZ_CRASH("Unexpected align-content value");
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
CrossAxisPositionTracker::TraversePackingSpace()
|
|
{
|
|
if (mNumPackingSpacesRemaining) {
|
|
MOZ_ASSERT(mAlignContent == NS_STYLE_ALIGN_CONTENT_SPACE_BETWEEN ||
|
|
mAlignContent == NS_STYLE_ALIGN_CONTENT_SPACE_AROUND,
|
|
"mNumPackingSpacesRemaining only applies for "
|
|
"space-between/space-around");
|
|
|
|
MOZ_ASSERT(mPackingSpaceRemaining >= 0,
|
|
"ran out of packing space earlier than we expected");
|
|
|
|
// NOTE: This integer math will skew the distribution of remainder
|
|
// app-units towards the end, which is fine.
|
|
nscoord curPackingSpace =
|
|
mPackingSpaceRemaining / mNumPackingSpacesRemaining;
|
|
|
|
mPosition += curPackingSpace;
|
|
mNumPackingSpacesRemaining--;
|
|
mPackingSpaceRemaining -= curPackingSpace;
|
|
}
|
|
}
|
|
|
|
SingleLineCrossAxisPositionTracker::
|
|
SingleLineCrossAxisPositionTracker(const FlexboxAxisTracker& aAxisTracker)
|
|
: PositionTracker(aAxisTracker.GetCrossAxis())
|
|
{
|
|
}
|
|
|
|
void
|
|
FlexLine::ComputeCrossSizeAndBaseline(const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
nscoord crossStartToFurthestBaseline= nscoord_MIN;
|
|
nscoord crossEndToFurthestBaseline = nscoord_MIN;
|
|
nscoord largestOuterCrossSize = 0;
|
|
for (uint32_t i = 0; i < mItems.Length(); ++i) {
|
|
const FlexItem& curItem = mItems[i];
|
|
nscoord curOuterCrossSize = curItem.GetCrossSize() +
|
|
curItem.GetMarginBorderPaddingSizeInAxis(aAxisTracker.GetCrossAxis());
|
|
|
|
if (curItem.GetAlignSelf() == NS_STYLE_ALIGN_ITEMS_BASELINE &&
|
|
curItem.GetNumAutoMarginsInAxis(aAxisTracker.GetCrossAxis()) == 0) {
|
|
// FIXME: Once we support "writing-mode", we'll have to do baseline
|
|
// alignment in vertical flex containers here (w/ horizontal cross-axes).
|
|
|
|
// Find distance from our item's cross-start and cross-end margin-box
|
|
// edges to its baseline.
|
|
//
|
|
// Here's a diagram of a flex-item that we might be doing this on.
|
|
// "mmm" is the margin-box, "bbb" is the border-box. The bottom of
|
|
// the text "BASE" is the baseline.
|
|
//
|
|
// ---(cross-start)---
|
|
// ___ ___ ___
|
|
// mmmmmmmmmmmm | |margin-start |
|
|
// m m | _|_ ___ |
|
|
// m bbbbbbbb m |curOuterCrossSize | |crossStartToBaseline
|
|
// m b b m | |ascent |
|
|
// m b BASE b m | _|_ _|_
|
|
// m b b m | |
|
|
// m bbbbbbbb m | |crossEndToBaseline
|
|
// m m | |
|
|
// mmmmmmmmmmmm _|_ _|_
|
|
//
|
|
// ---(cross-end)---
|
|
//
|
|
// We already have the curOuterCrossSize, margin-start, and the ascent.
|
|
// * We can get crossStartToBaseline by adding margin-start + ascent.
|
|
// * If we subtract that from the curOuterCrossSize, we get
|
|
// crossEndToBaseline.
|
|
|
|
nscoord crossStartToBaseline =
|
|
curItem.GetBaselineOffsetFromOuterCrossStart(aAxisTracker.GetCrossAxis());
|
|
nscoord crossEndToBaseline = curOuterCrossSize - crossStartToBaseline;
|
|
|
|
// Now, update our "largest" values for these (across all the flex items
|
|
// in this flex line), so we can use them in computing the line's cross
|
|
// size below:
|
|
crossStartToFurthestBaseline = std::max(crossStartToFurthestBaseline,
|
|
crossStartToBaseline);
|
|
crossEndToFurthestBaseline = std::max(crossEndToFurthestBaseline,
|
|
crossEndToBaseline);
|
|
} else {
|
|
largestOuterCrossSize = std::max(largestOuterCrossSize, curOuterCrossSize);
|
|
}
|
|
}
|
|
|
|
// The line's baseline is the distance from the cross-start edge to the
|
|
// furthest baseline. (The item(s) with that baseline will be exactly
|
|
// aligned with the line's cross-start edge.)
|
|
mBaselineOffsetFromCrossStart = crossStartToFurthestBaseline;
|
|
|
|
// The line's cross-size is the larger of:
|
|
// (a) [largest cross-start-to-baseline + largest baseline-to-cross-end] of
|
|
// all baseline-aligned items with no cross-axis auto margins...
|
|
// and
|
|
// (b) largest cross-size of all other children.
|
|
mLineCrossSize = std::max(crossStartToFurthestBaseline +
|
|
crossEndToFurthestBaseline,
|
|
largestOuterCrossSize);
|
|
}
|
|
|
|
void
|
|
FlexItem::ResolveStretchedCrossSize(nscoord aLineCrossSize,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
AxisOrientationType crossAxis = aAxisTracker.GetCrossAxis();
|
|
// We stretch IFF we are align-self:stretch, have no auto margins in
|
|
// cross axis, and have cross-axis size property == "auto". If any of those
|
|
// conditions don't hold up, we won't stretch.
|
|
if (mAlignSelf != NS_STYLE_ALIGN_ITEMS_STRETCH ||
|
|
GetNumAutoMarginsInAxis(crossAxis) != 0 ||
|
|
eStyleUnit_Auto != GetSizePropertyForAxis(mFrame, crossAxis).GetUnit()) {
|
|
return;
|
|
}
|
|
|
|
// If we've already been stretched, we can bail out early, too.
|
|
// No need to redo the calculation.
|
|
if (mIsStretched) {
|
|
return;
|
|
}
|
|
|
|
// Reserve space for margins & border & padding, and then use whatever
|
|
// remains as our item's cross-size (clamped to its min/max range).
|
|
nscoord stretchedSize = aLineCrossSize -
|
|
GetMarginBorderPaddingSizeInAxis(crossAxis);
|
|
|
|
stretchedSize = NS_CSS_MINMAX(stretchedSize, mCrossMinSize, mCrossMaxSize);
|
|
|
|
// Update the cross-size & make a note that it's stretched, so we know to
|
|
// override the reflow state's computed cross-size in our final reflow.
|
|
SetCrossSize(stretchedSize);
|
|
mIsStretched = true;
|
|
}
|
|
|
|
void
|
|
SingleLineCrossAxisPositionTracker::
|
|
ResolveAutoMarginsInCrossAxis(const FlexLine& aLine,
|
|
FlexItem& aItem)
|
|
{
|
|
// Subtract the space that our item is already occupying, to see how much
|
|
// space (if any) is available for its auto margins.
|
|
nscoord spaceForAutoMargins = aLine.GetLineCrossSize() -
|
|
(aItem.GetCrossSize() + aItem.GetMarginBorderPaddingSizeInAxis(mAxis));
|
|
|
|
if (spaceForAutoMargins <= 0) {
|
|
return; // No available space --> nothing to do
|
|
}
|
|
|
|
uint32_t numAutoMargins = aItem.GetNumAutoMarginsInAxis(mAxis);
|
|
if (numAutoMargins == 0) {
|
|
return; // No auto margins --> nothing to do.
|
|
}
|
|
|
|
// OK, we have at least one auto margin and we have some available space.
|
|
// Give each auto margin a share of the space.
|
|
const nsStyleSides& styleMargin = aItem.Frame()->StyleMargin()->mMargin;
|
|
for (uint32_t i = 0; i < eNumAxisEdges; i++) {
|
|
Side side = kAxisOrientationToSidesMap[mAxis][i];
|
|
if (styleMargin.GetUnit(side) == eStyleUnit_Auto) {
|
|
MOZ_ASSERT(aItem.GetMarginComponentForSide(side) == 0,
|
|
"Expecting auto margins to have value '0' before we "
|
|
"update them");
|
|
|
|
// NOTE: integer divison is fine here; numAutoMargins is either 1 or 2.
|
|
// If it's 2 & spaceForAutoMargins is odd, 1st margin gets smaller half.
|
|
nscoord curAutoMarginSize = spaceForAutoMargins / numAutoMargins;
|
|
aItem.SetMarginComponentForSide(side, curAutoMarginSize);
|
|
numAutoMargins--;
|
|
spaceForAutoMargins -= curAutoMarginSize;
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
SingleLineCrossAxisPositionTracker::
|
|
EnterAlignPackingSpace(const FlexLine& aLine,
|
|
const FlexItem& aItem)
|
|
{
|
|
// We don't do align-self alignment on items that have auto margins
|
|
// in the cross axis.
|
|
if (aItem.GetNumAutoMarginsInAxis(mAxis)) {
|
|
return;
|
|
}
|
|
|
|
switch (aItem.GetAlignSelf()) {
|
|
case NS_STYLE_ALIGN_ITEMS_FLEX_START:
|
|
case NS_STYLE_ALIGN_ITEMS_STRETCH:
|
|
// No space to skip over -- we're done.
|
|
// NOTE: 'stretch' behaves like 'flex-start' once we've stretched any
|
|
// auto-sized items (which we've already done).
|
|
break;
|
|
case NS_STYLE_ALIGN_ITEMS_FLEX_END:
|
|
mPosition +=
|
|
aLine.GetLineCrossSize() -
|
|
(aItem.GetCrossSize() +
|
|
aItem.GetMarginBorderPaddingSizeInAxis(mAxis));
|
|
break;
|
|
case NS_STYLE_ALIGN_ITEMS_CENTER:
|
|
// Note: If cross-size is odd, the "after" space will get the extra unit.
|
|
mPosition +=
|
|
(aLine.GetLineCrossSize() -
|
|
(aItem.GetCrossSize() +
|
|
aItem.GetMarginBorderPaddingSizeInAxis(mAxis))) / 2;
|
|
break;
|
|
case NS_STYLE_ALIGN_ITEMS_BASELINE: {
|
|
nscoord lineBaselineOffset =
|
|
aLine.GetBaselineOffsetFromCrossStart();
|
|
nscoord itemBaselineOffset =
|
|
aItem.GetBaselineOffsetFromOuterCrossStart(mAxis);
|
|
MOZ_ASSERT(lineBaselineOffset >= itemBaselineOffset,
|
|
"failed at finding largest baseline offset");
|
|
|
|
// Advance so that aItem's baseline is aligned with the line's baseline.
|
|
mPosition += (lineBaselineOffset - itemBaselineOffset);
|
|
break;
|
|
}
|
|
default:
|
|
NS_NOTREACHED("Unexpected align-self value");
|
|
break;
|
|
}
|
|
}
|
|
|
|
FlexboxAxisTracker::FlexboxAxisTracker(nsFlexContainerFrame* aFlexContainerFrame)
|
|
{
|
|
const nsStylePosition* pos = aFlexContainerFrame->StylePosition();
|
|
uint32_t flexDirection = pos->mFlexDirection;
|
|
uint32_t cssDirection =
|
|
aFlexContainerFrame->StyleVisibility()->mDirection;
|
|
|
|
MOZ_ASSERT(cssDirection == NS_STYLE_DIRECTION_LTR ||
|
|
cssDirection == NS_STYLE_DIRECTION_RTL,
|
|
"Unexpected computed value for 'direction' property");
|
|
// (Not asserting for flexDirection here; it's checked by the switch below.)
|
|
|
|
// These are defined according to writing-modes' definitions of
|
|
// start/end (for the inline dimension) and before/after (for the block
|
|
// dimension), here:
|
|
// http://www.w3.org/TR/css3-writing-modes/#logical-directions
|
|
// (NOTE: I'm intentionally not calling this "inlineAxis"/"blockAxis", since
|
|
// those terms have explicit definition in the writing-modes spec, which are
|
|
// the opposite of how I'd be using them here.)
|
|
// XXXdholbert Once we support the 'writing-mode' property, use its value
|
|
// here to further customize inlineDimension & blockDimension.
|
|
|
|
// Inline dimension ("start-to-end"):
|
|
AxisOrientationType inlineDimension =
|
|
cssDirection == NS_STYLE_DIRECTION_RTL ? eAxis_RL : eAxis_LR;
|
|
|
|
// Block dimension ("before-to-after"):
|
|
AxisOrientationType blockDimension = eAxis_TB;
|
|
|
|
// Determine main axis:
|
|
switch (flexDirection) {
|
|
case NS_STYLE_FLEX_DIRECTION_ROW:
|
|
mMainAxis = inlineDimension;
|
|
break;
|
|
case NS_STYLE_FLEX_DIRECTION_ROW_REVERSE:
|
|
mMainAxis = GetReverseAxis(inlineDimension);
|
|
break;
|
|
case NS_STYLE_FLEX_DIRECTION_COLUMN:
|
|
mMainAxis = blockDimension;
|
|
break;
|
|
case NS_STYLE_FLEX_DIRECTION_COLUMN_REVERSE:
|
|
mMainAxis = GetReverseAxis(blockDimension);
|
|
break;
|
|
default:
|
|
MOZ_CRASH("Unexpected computed value for 'flex-flow' property");
|
|
}
|
|
|
|
// Determine cross axis:
|
|
// (This is set up so that a bogus |flexDirection| value will
|
|
// give us blockDimension.
|
|
if (flexDirection == NS_STYLE_FLEX_DIRECTION_COLUMN ||
|
|
flexDirection == NS_STYLE_FLEX_DIRECTION_COLUMN_REVERSE) {
|
|
mCrossAxis = inlineDimension;
|
|
} else {
|
|
mCrossAxis = blockDimension;
|
|
}
|
|
|
|
// "flex-wrap: wrap-reverse" reverses our cross axis.
|
|
if (pos->mFlexWrap == NS_STYLE_FLEX_WRAP_WRAP_REVERSE) {
|
|
mCrossAxis = GetReverseAxis(mCrossAxis);
|
|
}
|
|
|
|
MOZ_ASSERT(IsAxisHorizontal(mMainAxis) != IsAxisHorizontal(mCrossAxis),
|
|
"main & cross axes should be in different dimensions");
|
|
}
|
|
|
|
nsresult
|
|
nsFlexContainerFrame::GenerateFlexLines(
|
|
nsPresContext* aPresContext,
|
|
const nsHTMLReflowState& aReflowState,
|
|
nscoord aContentBoxMainSize,
|
|
nscoord aAvailableHeightForContent,
|
|
const FlexboxAxisTracker& aAxisTracker,
|
|
nsTArray<FlexLine>& aLines)
|
|
{
|
|
MOZ_ASSERT(aLines.IsEmpty(), "Expecting outparam to start out empty");
|
|
|
|
const bool isSingleLine =
|
|
NS_STYLE_FLEX_WRAP_NOWRAP == aReflowState.mStylePosition->mFlexWrap;
|
|
|
|
// We have at least one FlexLine. Even an empty flex container has a single
|
|
// (empty) flex line.
|
|
FlexLine* curLine = aLines.AppendElement();
|
|
|
|
nscoord wrapThreshold;
|
|
if (isSingleLine) {
|
|
// Not wrapping. Set threshold to sentinel value that tells us not to wrap.
|
|
wrapThreshold = NS_UNCONSTRAINEDSIZE;
|
|
|
|
// Optimization: We know all items will end up in the first line, so we can
|
|
// pre-allocate space for them.
|
|
curLine->mItems.SetCapacity(mFrames.GetLength());
|
|
} else {
|
|
// Wrapping! Set wrap threshold to flex container's content-box main-size.
|
|
wrapThreshold = aContentBoxMainSize;
|
|
|
|
// If the flex container doesn't have a definite content-box main-size
|
|
// (e.g. if we're 'height:auto'), make sure we at least wrap when we hit
|
|
// its max main-size.
|
|
if (wrapThreshold == NS_UNCONSTRAINEDSIZE) {
|
|
const nscoord flexContainerMaxMainSize =
|
|
GET_MAIN_COMPONENT(aAxisTracker,
|
|
aReflowState.ComputedMaxWidth(),
|
|
aReflowState.ComputedMaxHeight());
|
|
|
|
wrapThreshold = flexContainerMaxMainSize;
|
|
}
|
|
|
|
// Also: if we're vertical and paginating, we may need to wrap sooner
|
|
// (before we run off the end of the page)
|
|
if (!IsAxisHorizontal(aAxisTracker.GetMainAxis()) &&
|
|
aAvailableHeightForContent != NS_UNCONSTRAINEDSIZE) {
|
|
wrapThreshold = std::min(wrapThreshold, aAvailableHeightForContent);
|
|
}
|
|
}
|
|
|
|
for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
|
|
nsIFrame* childFrame = e.get();
|
|
|
|
// Honor "page-break-before", if we're multi-line and this line isn't empty:
|
|
if (!isSingleLine && !curLine->mItems.IsEmpty() &&
|
|
childFrame->StyleDisplay()->mBreakBefore) {
|
|
curLine = aLines.AppendElement();
|
|
}
|
|
|
|
FlexItem* item = curLine->mItems.AppendElement(
|
|
GenerateFlexItemForChild(aPresContext, childFrame,
|
|
aReflowState, aAxisTracker));
|
|
|
|
nsresult rv = ResolveFlexItemMaxContentSizing(aPresContext, *item,
|
|
aReflowState, aAxisTracker);
|
|
NS_ENSURE_SUCCESS(rv,rv);
|
|
nscoord itemInnerHypotheticalMainSize = item->GetMainSize();
|
|
nscoord itemOuterHypotheticalMainSize = item->GetMainSize() +
|
|
item->GetMarginBorderPaddingSizeInAxis(aAxisTracker.GetMainAxis());
|
|
|
|
// Check if we need to wrap |item| to a new line
|
|
// (i.e. check if its outer hypothetical main size pushes our line over
|
|
// the threshold)
|
|
if (wrapThreshold != NS_UNCONSTRAINEDSIZE &&
|
|
curLine->mItems.Length() > 1 && // Don't wrap if it'll leave line empty
|
|
wrapThreshold < (curLine->GetTotalOuterHypotheticalMainSize() +
|
|
itemOuterHypotheticalMainSize)) {
|
|
// Need to wrap to a new line! Create a new line, create a copy of the
|
|
// newest FlexItem there, and clear that FlexItem out of the prev. line.
|
|
curLine = aLines.AppendElement();
|
|
// NOTE: if that^ AppendElement had to realloc, then |item| may now
|
|
// point to bogus memory. Null out our pointer and use a freshly-obtained
|
|
// reference ('itemToCopy'), to be on the safe side.
|
|
item = nullptr;
|
|
|
|
FlexLine& prevLine = aLines[aLines.Length() - 2];
|
|
uint32_t itemIdxInPrevLine = prevLine.mItems.Length() - 1;
|
|
FlexItem& itemToCopy = prevLine.mItems[itemIdxInPrevLine];
|
|
|
|
// Copy item into cur line:
|
|
curLine->mItems.AppendElement(itemToCopy);
|
|
// ...and remove the old copy in prev line:
|
|
prevLine.mItems.RemoveElementAt(itemIdxInPrevLine);
|
|
}
|
|
|
|
curLine->AddToMainSizeTotals(itemInnerHypotheticalMainSize,
|
|
itemOuterHypotheticalMainSize);
|
|
|
|
// Honor "page-break-after", if we're multi-line and have more children:
|
|
if (!isSingleLine && childFrame->GetNextSibling() &&
|
|
childFrame->StyleDisplay()->mBreakAfter) {
|
|
curLine = aLines.AppendElement();
|
|
}
|
|
}
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
// Retrieves the content-box main-size of our flex container from the
|
|
// reflow state (specifically, the main-size of *this continuation* of the
|
|
// flex container).
|
|
nscoord
|
|
nsFlexContainerFrame::GetMainSizeFromReflowState(
|
|
const nsHTMLReflowState& aReflowState,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
if (IsAxisHorizontal(aAxisTracker.GetMainAxis())) {
|
|
// Horizontal case is easy -- our main size is our computed width
|
|
// (which is already resolved).
|
|
return aReflowState.ComputedWidth();
|
|
}
|
|
|
|
return GetEffectiveComputedHeight(aReflowState);
|
|
}
|
|
|
|
// Returns the largest outer hypothetical main-size of any line in |aLines|.
|
|
// (i.e. the hypothetical main-size of the largest line)
|
|
static nscoord
|
|
GetLargestLineMainSize(const nsTArray<FlexLine>& aLines)
|
|
{
|
|
nscoord largestLineOuterSize = 0;
|
|
for (uint32_t lineIdx = 0; lineIdx < aLines.Length(); lineIdx++) {
|
|
largestLineOuterSize =
|
|
std::max(largestLineOuterSize,
|
|
aLines[lineIdx].GetTotalOuterHypotheticalMainSize());
|
|
}
|
|
return largestLineOuterSize;
|
|
}
|
|
|
|
// Returns the content-box main-size of our flex container, based on the
|
|
// available height (if appropriate) and the main-sizes of the flex items.
|
|
static nscoord
|
|
ClampFlexContainerMainSize(const nsHTMLReflowState& aReflowState,
|
|
const FlexboxAxisTracker& aAxisTracker,
|
|
nscoord aUnclampedMainSize,
|
|
nscoord aAvailableHeightForContent,
|
|
const nsTArray<FlexLine>& aLines,
|
|
nsReflowStatus& aStatus)
|
|
{
|
|
if (IsAxisHorizontal(aAxisTracker.GetMainAxis())) {
|
|
// Horizontal case is easy -- our main size should already be resolved
|
|
// before we get a call to Reflow. We don't have to worry about doing
|
|
// page-breaking or shrinkwrapping in the horizontal axis.
|
|
return aUnclampedMainSize;
|
|
}
|
|
|
|
if (aUnclampedMainSize != NS_INTRINSICSIZE) {
|
|
// Vertical case, with fixed height:
|
|
if (aAvailableHeightForContent == NS_UNCONSTRAINEDSIZE ||
|
|
aUnclampedMainSize < aAvailableHeightForContent) {
|
|
// Not in a fragmenting context, OR no need to fragment because we have
|
|
// more available height than we need. Either way, just use our fixed
|
|
// height. (Note that the reflow state has already done the appropriate
|
|
// min/max-height clamping.)
|
|
return aUnclampedMainSize;
|
|
}
|
|
|
|
// Fragmenting *and* our fixed height is too tall for available height:
|
|
// Mark incomplete so we get a next-in-flow, and take up all of the
|
|
// available height (or the amount of height required by our children, if
|
|
// that's larger; but of course not more than our own computed height).
|
|
// XXXdholbert For now, we don't support pushing children to our next
|
|
// continuation or splitting children, so "amount of height required by
|
|
// our children" is just the sum of our children's heights.
|
|
NS_FRAME_SET_INCOMPLETE(aStatus);
|
|
nscoord largestLineOuterSize = GetLargestLineMainSize(aLines);
|
|
|
|
if (largestLineOuterSize <= aAvailableHeightForContent) {
|
|
return aAvailableHeightForContent;
|
|
}
|
|
return std::min(aUnclampedMainSize, largestLineOuterSize);
|
|
}
|
|
|
|
// Vertical case, with auto-height:
|
|
// Resolve auto-height to the largest FlexLine-length, clamped to our
|
|
// computed min/max main-size properties (min-height & max-height).
|
|
// XXXdholbert Handle constrained-aAvailableHeightForContent case here.
|
|
nscoord largestLineOuterSize = GetLargestLineMainSize(aLines);
|
|
return NS_CSS_MINMAX(largestLineOuterSize,
|
|
aReflowState.ComputedMinHeight(),
|
|
aReflowState.ComputedMaxHeight());
|
|
}
|
|
|
|
// Returns the sum of the cross sizes of all the lines in |aLines|
|
|
static nscoord
|
|
SumLineCrossSizes(const nsTArray<FlexLine>& aLines)
|
|
{
|
|
nscoord sum = 0;
|
|
for (uint32_t lineIdx = 0; lineIdx < aLines.Length(); lineIdx++) {
|
|
sum += aLines[lineIdx].GetLineCrossSize();
|
|
}
|
|
return sum;
|
|
}
|
|
|
|
nscoord
|
|
nsFlexContainerFrame::ComputeCrossSize(const nsHTMLReflowState& aReflowState,
|
|
const FlexboxAxisTracker& aAxisTracker,
|
|
const nsTArray<FlexLine>& aLines,
|
|
nscoord aAvailableHeightForContent,
|
|
bool* aIsDefinite,
|
|
nsReflowStatus& aStatus)
|
|
{
|
|
MOZ_ASSERT(aIsDefinite, "outparam pointer must be non-null");
|
|
|
|
if (IsAxisHorizontal(aAxisTracker.GetCrossAxis())) {
|
|
// Cross axis is horizontal: our cross size is our computed width
|
|
// (which is already resolved).
|
|
*aIsDefinite = true;
|
|
return aReflowState.ComputedWidth();
|
|
}
|
|
|
|
nscoord effectiveComputedHeight = GetEffectiveComputedHeight(aReflowState);
|
|
if (effectiveComputedHeight != NS_INTRINSICSIZE) {
|
|
// Cross-axis is vertical, and we have a fixed height:
|
|
*aIsDefinite = true;
|
|
if (aAvailableHeightForContent == NS_UNCONSTRAINEDSIZE ||
|
|
effectiveComputedHeight < aAvailableHeightForContent) {
|
|
// Not in a fragmenting context, OR no need to fragment because we have
|
|
// more available height than we need. Either way, just use our fixed
|
|
// height. (Note that the reflow state has already done the appropriate
|
|
// min/max-height clamping.)
|
|
return effectiveComputedHeight;
|
|
}
|
|
|
|
// Fragmenting *and* our fixed height is too tall for available height:
|
|
// Mark incomplete so we get a next-in-flow, and take up all of the
|
|
// available height (or the amount of height required by our children, if
|
|
// that's larger; but of course not more than our own computed height).
|
|
// XXXdholbert For now, we don't support pushing children to our next
|
|
// continuation or splitting children, so "amount of height required by
|
|
// our children" is just our line-height.
|
|
NS_FRAME_SET_INCOMPLETE(aStatus);
|
|
nscoord sumOfLineCrossSizes = SumLineCrossSizes(aLines);
|
|
if (sumOfLineCrossSizes <= aAvailableHeightForContent) {
|
|
return aAvailableHeightForContent;
|
|
}
|
|
return std::min(effectiveComputedHeight, sumOfLineCrossSizes);
|
|
}
|
|
|
|
// Cross axis is vertical and we have auto-height: shrink-wrap our line(s),
|
|
// subject to our min-size / max-size constraints in that (vertical) axis.
|
|
// XXXdholbert Handle constrained-aAvailableHeightForContent case here.
|
|
*aIsDefinite = false;
|
|
return NS_CSS_MINMAX(SumLineCrossSizes(aLines),
|
|
aReflowState.ComputedMinHeight(),
|
|
aReflowState.ComputedMaxHeight());
|
|
}
|
|
|
|
void
|
|
FlexLine::PositionItemsInMainAxis(uint8_t aJustifyContent,
|
|
nscoord aContentBoxMainSize,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
MainAxisPositionTracker mainAxisPosnTracker(aAxisTracker, mItems,
|
|
aJustifyContent,
|
|
aContentBoxMainSize);
|
|
for (uint32_t i = 0; i < mItems.Length(); ++i) {
|
|
FlexItem& item = mItems[i];
|
|
|
|
nscoord itemMainBorderBoxSize =
|
|
item.GetMainSize() +
|
|
item.GetBorderPaddingSizeInAxis(mainAxisPosnTracker.GetAxis());
|
|
|
|
// Resolve any main-axis 'auto' margins on aChild to an actual value.
|
|
mainAxisPosnTracker.ResolveAutoMarginsInMainAxis(item);
|
|
|
|
// Advance our position tracker to child's upper-left content-box corner,
|
|
// and use that as its position in the main axis.
|
|
mainAxisPosnTracker.EnterMargin(item.GetMargin());
|
|
mainAxisPosnTracker.EnterChildFrame(itemMainBorderBoxSize);
|
|
|
|
item.SetMainPosition(mainAxisPosnTracker.GetPosition());
|
|
|
|
mainAxisPosnTracker.ExitChildFrame(itemMainBorderBoxSize);
|
|
mainAxisPosnTracker.ExitMargin(item.GetMargin());
|
|
mainAxisPosnTracker.TraversePackingSpace();
|
|
}
|
|
}
|
|
|
|
// Helper method to take care of children who ASK_FOR_BASELINE, when
|
|
// we need their baseline.
|
|
static void
|
|
ResolveReflowedChildAscent(nsIFrame* aFrame,
|
|
nsHTMLReflowMetrics& aChildDesiredSize)
|
|
{
|
|
if (aChildDesiredSize.TopAscent() == nsHTMLReflowMetrics::ASK_FOR_BASELINE) {
|
|
// Use GetFirstLineBaseline(), or just GetBaseline() if that fails.
|
|
nscoord ascent;
|
|
if (nsLayoutUtils::GetFirstLineBaseline(aFrame, &ascent)) {
|
|
aChildDesiredSize.SetTopAscent(ascent);
|
|
} else {
|
|
aChildDesiredSize.SetTopAscent(aFrame->GetBaseline());
|
|
}
|
|
}
|
|
}
|
|
|
|
nsresult
|
|
nsFlexContainerFrame::SizeItemInCrossAxis(
|
|
nsPresContext* aPresContext,
|
|
const FlexboxAxisTracker& aAxisTracker,
|
|
nsHTMLReflowState& aChildReflowState,
|
|
FlexItem& aItem)
|
|
{
|
|
// In vertical flexbox (with horizontal cross-axis), we can just trust the
|
|
// reflow state's computed-width as our cross-size. We also don't need to
|
|
// record the baseline because we'll have converted any "align-self:baseline"
|
|
// items to be "align-self:flex-start" in the FlexItem constructor.
|
|
// FIXME: Once we support writing-mode (vertical text), we will be able to
|
|
// have baseline-aligned items in a vertical flexbox, and we'll need to
|
|
// record baseline information here.
|
|
if (IsAxisHorizontal(aAxisTracker.GetCrossAxis())) {
|
|
MOZ_ASSERT(aItem.GetAlignSelf() != NS_STYLE_ALIGN_ITEMS_BASELINE,
|
|
"In vert flex container, we depend on FlexItem constructor to "
|
|
"convert 'align-self: baseline' to 'align-self: flex-start'");
|
|
aItem.SetCrossSize(aChildReflowState.ComputedWidth());
|
|
return NS_OK;
|
|
}
|
|
|
|
MOZ_ASSERT(!aItem.HadMeasuringReflow(),
|
|
"We shouldn't need more than one measuring reflow");
|
|
|
|
if (aItem.GetAlignSelf() == NS_STYLE_ALIGN_ITEMS_STRETCH) {
|
|
// This item's got "align-self: stretch", so we probably imposed a
|
|
// stretched computed height on it during its previous reflow. We're
|
|
// not imposing that height for *this* measuring reflow, so we need to
|
|
// tell it to treat this reflow as a vertical resize (regardless of
|
|
// whether any of its ancestors are being resized).
|
|
aChildReflowState.mFlags.mVResize = true;
|
|
}
|
|
nsHTMLReflowMetrics childDesiredSize(aChildReflowState.GetWritingMode());
|
|
nsReflowStatus childReflowStatus;
|
|
const uint32_t flags = NS_FRAME_NO_MOVE_FRAME;
|
|
nsresult rv = ReflowChild(aItem.Frame(), aPresContext,
|
|
childDesiredSize, aChildReflowState,
|
|
0, 0, flags, childReflowStatus);
|
|
aItem.SetHadMeasuringReflow();
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
// XXXdholbert Once we do pagination / splitting, we'll need to actually
|
|
// handle incomplete childReflowStatuses. But for now, we give our kids
|
|
// unconstrained available height, which means they should always complete.
|
|
MOZ_ASSERT(NS_FRAME_IS_COMPLETE(childReflowStatus),
|
|
"We gave flex item unconstrained available height, so it "
|
|
"should be complete");
|
|
|
|
// Tell the child we're done with its initial reflow.
|
|
// (Necessary for e.g. GetBaseline() to work below w/out asserting)
|
|
rv = FinishReflowChild(aItem.Frame(), aPresContext,
|
|
&aChildReflowState, childDesiredSize, 0, 0, flags);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
// Save the sizing info that we learned from this reflow
|
|
// -----------------------------------------------------
|
|
|
|
// Tentatively store the child's desired content-box cross-size.
|
|
// Note that childDesiredSize is the border-box size, so we have to
|
|
// subtract border & padding to get the content-box size.
|
|
// (Note that at this point in the code, we know our cross axis is vertical,
|
|
// so we don't bother with making aAxisTracker pick the cross-axis component
|
|
// for us.)
|
|
nscoord crossAxisBorderPadding = aItem.GetBorderPadding().TopBottom();
|
|
if (childDesiredSize.Height() < crossAxisBorderPadding) {
|
|
// Child's requested size isn't large enough for its border/padding!
|
|
// This is OK for the trivial nsFrame::Reflow() impl, but other frame
|
|
// classes should know better. So, if we get here, the child had better be
|
|
// an instance of nsFrame (i.e. it should return null from GetType()).
|
|
// XXXdholbert Once we've fixed bug 765861, we should upgrade this to an
|
|
// assertion that trivially passes if bug 765861's flag has been flipped.
|
|
NS_WARN_IF_FALSE(!aItem.Frame()->GetType(),
|
|
"Child should at least request space for border/padding");
|
|
aItem.SetCrossSize(0);
|
|
} else {
|
|
// (normal case)
|
|
aItem.SetCrossSize(childDesiredSize.Height() - crossAxisBorderPadding);
|
|
}
|
|
|
|
// If we need to do baseline-alignment, store the child's ascent.
|
|
if (aItem.GetAlignSelf() == NS_STYLE_ALIGN_ITEMS_BASELINE) {
|
|
ResolveReflowedChildAscent(aItem.Frame(), childDesiredSize);
|
|
aItem.SetAscent(childDesiredSize.TopAscent());
|
|
}
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
void
|
|
FlexLine::PositionItemsInCrossAxis(nscoord aLineStartPosition,
|
|
const FlexboxAxisTracker& aAxisTracker)
|
|
{
|
|
SingleLineCrossAxisPositionTracker lineCrossAxisPosnTracker(aAxisTracker);
|
|
|
|
for (uint32_t i = 0; i < mItems.Length(); ++i) {
|
|
FlexItem& item = mItems[i];
|
|
// First, stretch the item's cross size (if appropriate), and resolve any
|
|
// auto margins in this axis.
|
|
item.ResolveStretchedCrossSize(mLineCrossSize, aAxisTracker);
|
|
lineCrossAxisPosnTracker.ResolveAutoMarginsInCrossAxis(*this, item);
|
|
|
|
// Compute the cross-axis position of this item
|
|
nscoord itemCrossBorderBoxSize =
|
|
item.GetCrossSize() +
|
|
item.GetBorderPaddingSizeInAxis(aAxisTracker.GetCrossAxis());
|
|
lineCrossAxisPosnTracker.EnterAlignPackingSpace(*this, item);
|
|
lineCrossAxisPosnTracker.EnterMargin(item.GetMargin());
|
|
lineCrossAxisPosnTracker.EnterChildFrame(itemCrossBorderBoxSize);
|
|
|
|
item.SetCrossPosition(aLineStartPosition +
|
|
lineCrossAxisPosnTracker.GetPosition());
|
|
|
|
// Back out to cross-axis edge of the line.
|
|
lineCrossAxisPosnTracker.ResetPosition();
|
|
}
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsFlexContainerFrame::Reflow(nsPresContext* aPresContext,
|
|
nsHTMLReflowMetrics& aDesiredSize,
|
|
const nsHTMLReflowState& aReflowState,
|
|
nsReflowStatus& aStatus)
|
|
{
|
|
DO_GLOBAL_REFLOW_COUNT("nsFlexContainerFrame");
|
|
DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
|
|
PR_LOG(GetFlexContainerLog(), PR_LOG_DEBUG,
|
|
("Reflow() for nsFlexContainerFrame %p\n", this));
|
|
|
|
if (IsFrameTreeTooDeep(aReflowState, aDesiredSize, aStatus)) {
|
|
return NS_OK;
|
|
}
|
|
|
|
aStatus = NS_FRAME_COMPLETE;
|
|
|
|
// We (and our children) can only depend on our ancestor's height if we have
|
|
// a percent-height, or if we're positioned and we have "top" and "bottom"
|
|
// set and have height:auto. (There are actually other cases, too -- e.g. if
|
|
// our parent is itself a vertical flex container and we're flexible -- but
|
|
// we'll let our ancestors handle those sorts of cases.)
|
|
const nsStylePosition* stylePos = StylePosition();
|
|
if (stylePos->mHeight.HasPercent() ||
|
|
(StyleDisplay()->IsAbsolutelyPositionedStyle() &&
|
|
eStyleUnit_Auto == stylePos->mHeight.GetUnit() &&
|
|
eStyleUnit_Auto != stylePos->mOffset.GetTopUnit() &&
|
|
eStyleUnit_Auto != stylePos->mOffset.GetBottomUnit())) {
|
|
AddStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
SanityCheckAnonymousFlexItems();
|
|
#endif // DEBUG
|
|
|
|
// If we've never reordered our children, then we can trust that they're
|
|
// already in DOM-order, and we only need to consider their "order" property
|
|
// when checking them for sortedness & sorting them.
|
|
//
|
|
// After we actually sort them, though, we can't trust that they're in DOM
|
|
// order anymore. So, from that point on, our sort & sorted-order-checking
|
|
// operations need to use a fancier LEQ function that also takes DOM order
|
|
// into account, so that we can honor the spec's requirement that frames w/
|
|
// equal "order" values are laid out in DOM order.
|
|
if (!mChildrenHaveBeenReordered) {
|
|
mChildrenHaveBeenReordered =
|
|
SortChildrenIfNeeded<IsOrderLEQ>();
|
|
} else {
|
|
SortChildrenIfNeeded<IsOrderLEQWithDOMFallback>();
|
|
}
|
|
|
|
const FlexboxAxisTracker axisTracker(this);
|
|
|
|
nscoord contentBoxMainSize = GetMainSizeFromReflowState(aReflowState,
|
|
axisTracker);
|
|
|
|
// If we're being fragmented into a constrained height, subtract off
|
|
// borderpadding-top from it, to get the available height for our
|
|
// content box. (Don't subtract if we're skipping top border/padding,
|
|
// though.)
|
|
nscoord availableHeightForContent = aReflowState.AvailableHeight();
|
|
if (availableHeightForContent != NS_UNCONSTRAINEDSIZE &&
|
|
!(GetSkipSides() & (1 << NS_SIDE_TOP))) {
|
|
availableHeightForContent -= aReflowState.ComputedPhysicalBorderPadding().top;
|
|
// (Don't let that push availableHeightForContent below zero, though):
|
|
availableHeightForContent = std::max(availableHeightForContent, 0);
|
|
}
|
|
|
|
// Generate an array of our flex items (already sorted), in a FlexLine.
|
|
nsAutoTArray<FlexLine, 1> lines;
|
|
nsresult rv = GenerateFlexLines(aPresContext, aReflowState,
|
|
contentBoxMainSize, availableHeightForContent,
|
|
axisTracker, lines);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
contentBoxMainSize =
|
|
ClampFlexContainerMainSize(aReflowState, axisTracker,
|
|
contentBoxMainSize, availableHeightForContent,
|
|
lines, aStatus);
|
|
|
|
for (uint32_t i = 0; i < lines.Length(); i++) {
|
|
lines[i].ResolveFlexibleLengths(contentBoxMainSize);
|
|
}
|
|
|
|
// Cross Size Determination - Flexbox spec section 9.4
|
|
// ===================================================
|
|
// Calculate the hypothetical cross size of each item:
|
|
for (uint32_t lineIdx = 0; lineIdx < lines.Length(); ++lineIdx) {
|
|
FlexLine& line = lines[lineIdx];
|
|
for (uint32_t i = 0; i < line.mItems.Length(); ++i) {
|
|
FlexItem& curItem = line.mItems[i];
|
|
|
|
// (If the item's already been stretched, then it already knows its
|
|
// cross size. Don't bother trying to recalculate it.)
|
|
if (!curItem.IsStretched()) {
|
|
nsHTMLReflowState childReflowState(aPresContext, aReflowState,
|
|
curItem.Frame(),
|
|
nsSize(aReflowState.ComputedWidth(),
|
|
NS_UNCONSTRAINEDSIZE));
|
|
// Override computed main-size
|
|
if (IsAxisHorizontal(axisTracker.GetMainAxis())) {
|
|
childReflowState.SetComputedWidth(curItem.GetMainSize());
|
|
} else {
|
|
childReflowState.SetComputedHeight(curItem.GetMainSize());
|
|
}
|
|
|
|
nsresult rv = SizeItemInCrossAxis(aPresContext, axisTracker,
|
|
childReflowState, curItem);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Calculate the cross size and (if necessary) baseline-alignment position
|
|
// for each of our flex lines:
|
|
for (uint32_t lineIdx = 0; lineIdx < lines.Length(); ++lineIdx) {
|
|
lines[lineIdx].ComputeCrossSizeAndBaseline(axisTracker);
|
|
}
|
|
|
|
bool isCrossSizeDefinite;
|
|
const nscoord contentBoxCrossSize =
|
|
ComputeCrossSize(aReflowState, axisTracker, lines,
|
|
availableHeightForContent, &isCrossSizeDefinite, aStatus);
|
|
|
|
// Set up state for cross-axis alignment, at a high level (outside the
|
|
// scope of a particular flex line)
|
|
CrossAxisPositionTracker
|
|
crossAxisPosnTracker(lines, aReflowState.mStylePosition->mAlignContent,
|
|
contentBoxCrossSize, isCrossSizeDefinite, axisTracker);
|
|
|
|
// Set the flex container's baseline, from the baseline-alignment position
|
|
// of the first line's baseline-aligned items.
|
|
nscoord flexContainerAscent;
|
|
nscoord firstLineBaselineOffset = lines[0].GetBaselineOffsetFromCrossStart();
|
|
if (firstLineBaselineOffset == nscoord_MIN) {
|
|
// No baseline-aligned flex items in first line --> just use a sentinel
|
|
// value for now, and we'll update it during final reflow.
|
|
flexContainerAscent = nscoord_MIN;
|
|
} else {
|
|
// Add the position of the first line to that line's baseline-alignment
|
|
// offset, to get the baseline offset with respect to the *container's*
|
|
// cross-start edge.
|
|
nscoord firstLineBaselineOffsetWRTContainer =
|
|
firstLineBaselineOffset + crossAxisPosnTracker.GetPosition();
|
|
|
|
// The container's ascent is that ^ offset, converted out of logical coords
|
|
// (into distance from top of content-box), plus the top border/padding
|
|
// (since ascent is measured with respect to the top of the border-box).
|
|
flexContainerAscent = aReflowState.ComputedPhysicalBorderPadding().top +
|
|
PhysicalPosFromLogicalPos(firstLineBaselineOffsetWRTContainer,
|
|
contentBoxCrossSize,
|
|
axisTracker.GetCrossAxis());
|
|
}
|
|
|
|
for (uint32_t lineIdx = 0; lineIdx < lines.Length(); ++lineIdx) {
|
|
FlexLine& line = lines[lineIdx];
|
|
|
|
// Main-Axis Alignment - Flexbox spec section 9.5
|
|
// ==============================================
|
|
line.PositionItemsInMainAxis(aReflowState.mStylePosition->mJustifyContent,
|
|
contentBoxMainSize,
|
|
axisTracker);
|
|
|
|
// Cross-Axis Alignment - Flexbox spec section 9.6
|
|
// ===============================================
|
|
line.PositionItemsInCrossAxis(crossAxisPosnTracker.GetPosition(),
|
|
axisTracker);
|
|
crossAxisPosnTracker.TraverseLine(line);
|
|
crossAxisPosnTracker.TraversePackingSpace();
|
|
}
|
|
|
|
// Before giving each child a final reflow, calculate the origin of the
|
|
// flex container's content box (with respect to its border-box), so that
|
|
// we can compute our flex item's final positions.
|
|
nsMargin containerBorderPadding(aReflowState.ComputedPhysicalBorderPadding());
|
|
ApplySkipSides(containerBorderPadding, &aReflowState);
|
|
const nsPoint containerContentBoxOrigin(containerBorderPadding.left,
|
|
containerBorderPadding.top);
|
|
|
|
// FINAL REFLOW: Give each child frame another chance to reflow, now that
|
|
// we know its final size and position.
|
|
for (uint32_t lineIdx = 0; lineIdx < lines.Length(); ++lineIdx) {
|
|
FlexLine& line = lines[lineIdx];
|
|
for (uint32_t i = 0; i < line.mItems.Length(); ++i) {
|
|
FlexItem& curItem = line.mItems[i];
|
|
|
|
nsPoint physicalPosn = axisTracker.PhysicalPointFromLogicalPoint(
|
|
curItem.GetMainPosition(),
|
|
curItem.GetCrossPosition(),
|
|
contentBoxMainSize,
|
|
contentBoxCrossSize);
|
|
// Adjust physicalPosn to be relative to the container's border-box
|
|
// (i.e. its frame rect), instead of the container's content-box:
|
|
physicalPosn += containerContentBoxOrigin;
|
|
|
|
nsHTMLReflowState childReflowState(aPresContext, aReflowState,
|
|
curItem.Frame(),
|
|
nsSize(aReflowState.ComputedWidth(),
|
|
NS_UNCONSTRAINEDSIZE));
|
|
|
|
// Keep track of whether we've overriden the child's computed height
|
|
// and/or width, so we can set its resize flags accordingly.
|
|
bool didOverrideComputedWidth = false;
|
|
bool didOverrideComputedHeight = false;
|
|
|
|
// Override computed main-size
|
|
if (IsAxisHorizontal(axisTracker.GetMainAxis())) {
|
|
childReflowState.SetComputedWidth(curItem.GetMainSize());
|
|
didOverrideComputedWidth = true;
|
|
} else {
|
|
childReflowState.SetComputedHeight(curItem.GetMainSize());
|
|
didOverrideComputedHeight = true;
|
|
}
|
|
|
|
// Override reflow state's computed cross-size, for stretched items.
|
|
if (curItem.IsStretched()) {
|
|
MOZ_ASSERT(curItem.GetAlignSelf() == NS_STYLE_ALIGN_ITEMS_STRETCH,
|
|
"stretched item w/o 'align-self: stretch'?");
|
|
if (IsAxisHorizontal(axisTracker.GetCrossAxis())) {
|
|
childReflowState.SetComputedWidth(curItem.GetCrossSize());
|
|
didOverrideComputedWidth = true;
|
|
} else {
|
|
// If this item's height is stretched, it's a relative height.
|
|
curItem.Frame()->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
|
|
childReflowState.SetComputedHeight(curItem.GetCrossSize());
|
|
didOverrideComputedHeight = true;
|
|
}
|
|
}
|
|
|
|
// XXXdholbert Might need to actually set the correct margins in the
|
|
// reflow state at some point, so that they can be saved on the frame for
|
|
// UsedMarginProperty(). Maybe doesn't matter though...?
|
|
|
|
// If we're overriding the computed width or height, *and* we had an
|
|
// earlier "measuring" reflow, then this upcoming reflow needs to be
|
|
// treated as a resize.
|
|
if (curItem.HadMeasuringReflow()) {
|
|
if (didOverrideComputedWidth) {
|
|
// (This is somewhat redundant, since the reflow state already
|
|
// sets mHResize whenever our computed width has changed since the
|
|
// previous reflow. Still, it's nice for symmetry, and it may become
|
|
// necessary once we support orthogonal flows.)
|
|
childReflowState.mFlags.mHResize = true;
|
|
}
|
|
if (didOverrideComputedHeight) {
|
|
childReflowState.mFlags.mVResize = true;
|
|
}
|
|
}
|
|
// NOTE: Be very careful about doing anything else with childReflowState
|
|
// after this point, because some of its methods (e.g. SetComputedWidth)
|
|
// internally call InitResizeFlags and stomp on mVResize & mHResize.
|
|
|
|
nsHTMLReflowMetrics childDesiredSize(childReflowState.GetWritingMode());
|
|
nsReflowStatus childReflowStatus;
|
|
nsresult rv = ReflowChild(curItem.Frame(), aPresContext,
|
|
childDesiredSize, childReflowState,
|
|
physicalPosn.x, physicalPosn.y,
|
|
0, childReflowStatus);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
// XXXdholbert Once we do pagination / splitting, we'll need to actually
|
|
// handle incomplete childReflowStatuses. But for now, we give our kids
|
|
// unconstrained available height, which means they should always
|
|
// complete.
|
|
MOZ_ASSERT(NS_FRAME_IS_COMPLETE(childReflowStatus),
|
|
"We gave flex item unconstrained available height, so it "
|
|
"should be complete");
|
|
|
|
childReflowState.ApplyRelativePositioning(&physicalPosn);
|
|
|
|
rv = FinishReflowChild(curItem.Frame(), aPresContext,
|
|
&childReflowState, childDesiredSize,
|
|
physicalPosn.x, physicalPosn.y, 0);
|
|
NS_ENSURE_SUCCESS(rv, rv);
|
|
|
|
// If this is our first child and we haven't established a baseline for
|
|
// the container yet (i.e. if we don't have 'align-self: baseline' on any
|
|
// children), then use this child's baseline as the container's baseline.
|
|
if (lineIdx == 0 && i == 0 && flexContainerAscent == nscoord_MIN) {
|
|
ResolveReflowedChildAscent(curItem.Frame(), childDesiredSize);
|
|
|
|
// (We use GetNormalPosition() instead of physicalPosn because we don't
|
|
// want relative positioning on the child to affect the baseline that we
|
|
// read from it).
|
|
flexContainerAscent = curItem.Frame()->GetNormalPosition().y +
|
|
childDesiredSize.TopAscent();
|
|
}
|
|
}
|
|
}
|
|
|
|
nsSize desiredContentBoxSize =
|
|
axisTracker.PhysicalSizeFromLogicalSizes(contentBoxMainSize,
|
|
contentBoxCrossSize);
|
|
|
|
aDesiredSize.Width() = desiredContentBoxSize.width +
|
|
containerBorderPadding.LeftRight();
|
|
// Does *NOT* include bottom border/padding yet (we add that a bit lower down)
|
|
aDesiredSize.Height() = desiredContentBoxSize.height +
|
|
containerBorderPadding.top;
|
|
|
|
if (flexContainerAscent == nscoord_MIN) {
|
|
// Still don't have our baseline set -- this happens if we have no
|
|
// children (or if our children are huge enough that they have nscoord_MIN
|
|
// as their baseline... in which case, we'll use the wrong baseline, but no
|
|
// big deal)
|
|
NS_WARN_IF_FALSE(lines[0].mItems.IsEmpty(),
|
|
"Have flex items but didn't get an ascent - that's odd "
|
|
"(or there are just gigantic sizes involved)");
|
|
// Per spec, just use the bottom of content-box.
|
|
flexContainerAscent = aDesiredSize.Height();
|
|
}
|
|
aDesiredSize.SetTopAscent(flexContainerAscent);
|
|
|
|
// Now: If we're complete, add bottom border/padding to desired height
|
|
// (unless that pushes us over available height, in which case we become
|
|
// incomplete (unless we already weren't asking for any height, in which case
|
|
// we stay complete to avoid looping forever)).
|
|
// NOTE: If we're auto-height, we allow our bottom border/padding to push us
|
|
// over the available height without requesting a continuation, for
|
|
// consistency with the behavior of "display:block" elements.
|
|
if (NS_FRAME_IS_COMPLETE(aStatus)) {
|
|
// NOTE: We can't use containerBorderPadding.bottom for this, because if
|
|
// we're auto-height, ApplySkipSides will have zeroed it (because it
|
|
// assumed we might get a continuation). We have the correct value in
|
|
// aReflowState.ComputedPhyiscalBorderPadding().bottom, though, so we use that.
|
|
nscoord desiredHeightWithBottomBP =
|
|
aDesiredSize.Height() + aReflowState.ComputedPhysicalBorderPadding().bottom;
|
|
|
|
if (aReflowState.AvailableHeight() == NS_UNCONSTRAINEDSIZE ||
|
|
aDesiredSize.Height() == 0 ||
|
|
desiredHeightWithBottomBP <= aReflowState.AvailableHeight() ||
|
|
aReflowState.ComputedHeight() == NS_INTRINSICSIZE) {
|
|
// Update desired height to include bottom border/padding
|
|
aDesiredSize.Height() = desiredHeightWithBottomBP;
|
|
} else {
|
|
// We couldn't fit bottom border/padding, so we'll need a continuation.
|
|
NS_FRAME_SET_INCOMPLETE(aStatus);
|
|
}
|
|
}
|
|
|
|
// Overflow area = union(my overflow area, kids' overflow areas)
|
|
aDesiredSize.SetOverflowAreasToDesiredBounds();
|
|
for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
|
|
ConsiderChildOverflow(aDesiredSize.mOverflowAreas, e.get());
|
|
}
|
|
|
|
FinishReflowWithAbsoluteFrames(aPresContext, aDesiredSize,
|
|
aReflowState, aStatus);
|
|
|
|
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize)
|
|
return NS_OK;
|
|
}
|
|
|
|
/* virtual */ nscoord
|
|
nsFlexContainerFrame::GetMinWidth(nsRenderingContext* aRenderingContext)
|
|
{
|
|
FlexboxAxisTracker axisTracker(this);
|
|
|
|
nscoord minWidth = 0;
|
|
for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
|
|
nscoord childMinWidth =
|
|
nsLayoutUtils::IntrinsicForContainer(aRenderingContext, e.get(),
|
|
nsLayoutUtils::MIN_WIDTH);
|
|
// For a horizontal single-line flex container, the intrinsic min width is
|
|
// the sum of its items' min widths.
|
|
// For a vertical flex container, or for a multi-line horizontal flex
|
|
// container, the intrinsic min width is the max of its items' min widths.
|
|
if (IsAxisHorizontal(axisTracker.GetMainAxis()) &&
|
|
NS_STYLE_FLEX_WRAP_NOWRAP == StylePosition()->mFlexWrap) {
|
|
minWidth += childMinWidth;
|
|
} else {
|
|
minWidth = std::max(minWidth, childMinWidth);
|
|
}
|
|
}
|
|
return minWidth;
|
|
}
|
|
|
|
/* virtual */ nscoord
|
|
nsFlexContainerFrame::GetPrefWidth(nsRenderingContext* aRenderingContext)
|
|
{
|
|
// XXXdholbert Optimization: We could cache our intrinsic widths like
|
|
// nsBlockFrame does (and return it early from this function if it's set).
|
|
// Whenever anything happens that might change it, set it to
|
|
// NS_INTRINSIC_WIDTH_UNKNOWN (like nsBlockFrame::MarkIntrinsicWidthsDirty
|
|
// does)
|
|
FlexboxAxisTracker axisTracker(this);
|
|
|
|
nscoord prefWidth = 0;
|
|
for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
|
|
nscoord childPrefWidth =
|
|
nsLayoutUtils::IntrinsicForContainer(aRenderingContext, e.get(),
|
|
nsLayoutUtils::PREF_WIDTH);
|
|
if (IsAxisHorizontal(axisTracker.GetMainAxis())) {
|
|
prefWidth += childPrefWidth;
|
|
} else {
|
|
prefWidth = std::max(prefWidth, childPrefWidth);
|
|
}
|
|
}
|
|
return prefWidth;
|
|
}
|