Add a concurrent flag to ASStackLayoutSpec that is off by default (#3148)

This commit is contained in:
Huy Nguyen 2017-03-08 16:33:50 +00:00 committed by GitHub
parent 21953c97ef
commit dd8cac4414
4 changed files with 29 additions and 17 deletions

View File

@ -59,11 +59,14 @@ NS_ASSUME_NONNULL_BEGIN
@property (nonatomic, assign) ASStackLayoutJustifyContent justifyContent;
/** Orientation of children along cross axis. Defaults to ASStackLayoutAlignItemsStretch */
@property (nonatomic, assign) ASStackLayoutAlignItems alignItems;
//TODO documentation. Defaults to ASStackLayoutFlexWrapNoWrap
/** Whether children are stacked into a single or multiple lines. Defaults to single line (ASStackLayoutFlexWrapNoWrap) */
@property (nonatomic, assign) ASStackLayoutFlexWrap flexWrap;
//TODO documentation. Defaults to ASStackLayoutAlignContentStart
/** Orientation of lines along cross axis if there are multiple lines. Defaults to ASStackLayoutAlignContentStart */
@property (nonatomic, assign) ASStackLayoutAlignContent alignContent;
/** Whether this stack can dispatch to other threads, regardless of which thread it's running on */
@property (nonatomic, assign, getter=isConcurrent) BOOL concurrent;
- (instancetype)init;
/**
@ -84,8 +87,9 @@ NS_ASSUME_NONNULL_BEGIN
@param spacing The spacing between the children
@param justifyContent If no children are flexible, this describes how to fill any extra space
@param alignItems Orientation of the children along the cross axis
@param flexWrap Whether children are stacked into a single or multiple lines
@param alignContent Orientation of lines along cross axis if there are multiple lines
@param children ASLayoutElement children to be positioned.
TODO documentation flex wrap and align content
*/
+ (instancetype)stackLayoutSpecWithDirection:(ASStackLayoutDirection)direction
spacing:(CGFloat)spacing

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@ -136,7 +136,7 @@
const ASStackLayoutSpecStyle style = {.direction = _direction, .spacing = _spacing, .justifyContent = _justifyContent, .alignItems = _alignItems, .flexWrap = _flexWrap, .alignContent = _alignContent};
const auto unpositionedLayout = ASStackUnpositionedLayout::compute(stackChildren, style, constrainedSize);
const auto unpositionedLayout = ASStackUnpositionedLayout::compute(stackChildren, style, constrainedSize, _concurrent);
const auto positionedLayout = ASStackPositionedLayout::compute(unpositionedLayout, style, constrainedSize);
if (style.direction == ASStackLayoutDirectionVertical) {

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@ -58,7 +58,8 @@ struct ASStackUnpositionedLayout {
/** Given a set of children, computes the unpositioned layouts for those children. */
static ASStackUnpositionedLayout compute(const std::vector<ASStackLayoutSpecChild> &children,
const ASStackLayoutSpecStyle &style,
const ASSizeRange &sizeRange);
const ASSizeRange &sizeRange,
const BOOL concurrent);
static CGFloat baselineForItem(const ASStackLayoutSpecStyle &style,
const ASStackLayoutSpecItem &l);

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@ -16,7 +16,6 @@
#import <AsyncDisplayKit/ASDispatch.h>
#import <AsyncDisplayKit/ASLayoutSpecUtilities.h>
#import <AsyncDisplayKit/ASLayoutElementStylePrivate.h>
#import <AsyncDisplayKit/ASThread.h>
CGFloat const kViolationEpsilon = 0.01;
@ -69,7 +68,7 @@ static ASLayout *crossChildLayout(const ASStackLayoutSpecChild &child,
return layout ? : [ASLayout layoutWithLayoutElement:child.element size:{0, 0}];
}
static void dispatchApplyIfNeeded(size_t iterationCount, void(^work)(size_t i))
static void dispatchApplyIfNeeded(size_t iterationCount, BOOL forced, void(^work)(size_t i))
{
if (iterationCount == 0) {
return;
@ -80,7 +79,8 @@ static void dispatchApplyIfNeeded(size_t iterationCount, void(^work)(size_t i))
return;
}
if (ASDisplayNodeThreadIsMain() == NO) {
// TODO Once the locking situation in ASDisplayNode has improved, always dispatch if on main
if (forced == NO) {
for (size_t i = 0; i < iterationCount; i++) {
work(i);
}
@ -196,10 +196,11 @@ CGFloat ASStackUnpositionedLayout::computeCrossViolation(const CGFloat crossDime
*/
static void stretchItemsAlongCrossDimension(std::vector<ASStackLayoutSpecItem> &items,
const ASStackLayoutSpecStyle &style,
const BOOL concurrent,
const CGSize parentSize,
const CGFloat crossSize)
{
dispatchApplyIfNeeded(items.size(), ^(size_t i) {
dispatchApplyIfNeeded(items.size(), concurrent, ^(size_t i) {
auto &item = items[i];
const ASStackLayoutAlignItems alignItems = alignment(item.child.style.alignSelf, style.alignItems);
if (alignItems == ASStackLayoutAlignItemsStretch) {
@ -222,6 +223,7 @@ static void stretchItemsAlongCrossDimension(std::vector<ASStackLayoutSpecItem> &
*/
static void stretchLinesAlongCrossDimension(std::vector<ASStackUnpositionedLine> &lines,
const ASStackLayoutSpecStyle &style,
const BOOL concurrent,
const ASSizeRange &sizeRange,
const CGSize parentSize)
{
@ -239,7 +241,7 @@ static void stretchLinesAlongCrossDimension(std::vector<ASStackUnpositionedLine>
line.crossSize += extraCrossSizePerLine;
}
stretchItemsAlongCrossDimension(line.items, style, parentSize, line.crossSize);
stretchItemsAlongCrossDimension(line.items, style, concurrent, parentSize, line.crossSize);
}
}
@ -425,10 +427,11 @@ ASDISPLAYNODE_INLINE BOOL isFlexibleInBothDirections(const ASStackLayoutSpecChil
*/
static void layoutFlexibleChildrenAtZeroSize(std::vector<ASStackLayoutSpecItem> &items,
const ASStackLayoutSpecStyle &style,
const BOOL concurrent,
const ASSizeRange &sizeRange,
const CGSize parentSize)
{
dispatchApplyIfNeeded(items.size(), ^(size_t i) {
dispatchApplyIfNeeded(items.size(), concurrent, ^(size_t i) {
auto &item = items[i];
if (isFlexibleInBothDirections(item.child)) {
item.layout = crossChildLayout(item.child,
@ -550,6 +553,7 @@ ASDISPLAYNODE_INLINE BOOL useOptimizedFlexing(const std::vector<ASStackLayoutSpe
*/
static void flexLinesAlongStackDimension(std::vector<ASStackUnpositionedLine> &lines,
const ASStackLayoutSpecStyle &style,
const BOOL concurrent,
const ASSizeRange &sizeRange,
const CGSize parentSize,
const BOOL useOptimizedFlexing)
@ -567,7 +571,7 @@ static void flexLinesAlongStackDimension(std::vector<ASStackUnpositionedLine> &l
if (flexFactorSum == 0) {
// If optimized flexing was used then we have to clean up the unsized children and lay them out at zero size.
if (useOptimizedFlexing) {
layoutFlexibleChildrenAtZeroSize(items, style, sizeRange, parentSize);
layoutFlexibleChildrenAtZeroSize(items, style, concurrent, sizeRange, parentSize);
}
return;
}
@ -591,7 +595,7 @@ static void flexLinesAlongStackDimension(std::vector<ASStackUnpositionedLine> &l
}
ASDisplayNodeCAssert(firstFlexItem != -1, @"At this point there must be at least 1 flexible item");
dispatchApplyIfNeeded(items.size(), ^(size_t i) {
dispatchApplyIfNeeded(items.size(), concurrent, ^(size_t i) {
auto &item = items[i];
const CGFloat currentFlexAdjustment = flexAdjustment(item);
// Children are consider inflexible if they do not need to make a flex adjustment.
@ -655,6 +659,7 @@ static std::vector<ASStackUnpositionedLine> collectChildrenIntoLines(const std::
*/
static void layoutItemsAlongUnconstrainedStackDimension(std::vector<ASStackLayoutSpecItem> &items,
const ASStackLayoutSpecStyle &style,
const BOOL concurrent,
const ASSizeRange &sizeRange,
const CGSize parentSize,
const BOOL useOptimizedFlexing)
@ -662,7 +667,7 @@ static void layoutItemsAlongUnconstrainedStackDimension(std::vector<ASStackLayou
const CGFloat minCrossDimension = crossDimension(style.direction, sizeRange.min);
const CGFloat maxCrossDimension = crossDimension(style.direction, sizeRange.max);
dispatchApplyIfNeeded(items.size(), ^(size_t i) {
dispatchApplyIfNeeded(items.size(), concurrent, ^(size_t i) {
auto &item = items[i];
if (useOptimizedFlexing && isFlexibleInBothDirections(item.child)) {
item.layout = [ASLayout layoutWithLayoutElement:item.child.element size:{0, 0}];
@ -680,7 +685,8 @@ static void layoutItemsAlongUnconstrainedStackDimension(std::vector<ASStackLayou
ASStackUnpositionedLayout ASStackUnpositionedLayout::compute(const std::vector<ASStackLayoutSpecChild> &children,
const ASStackLayoutSpecStyle &style,
const ASSizeRange &sizeRange)
const ASSizeRange &sizeRange,
const BOOL concurrent)
{
if (children.empty()) {
return {};
@ -705,6 +711,7 @@ ASStackUnpositionedLayout ASStackUnpositionedLayout::compute(const std::vector<A
// which determines whether we must grow or shrink the flexible children.
layoutItemsAlongUnconstrainedStackDimension(items,
style,
concurrent,
sizeRange,
parentSize,
optimizedFlexing);
@ -713,14 +720,14 @@ ASStackUnpositionedLayout ASStackUnpositionedLayout::compute(const std::vector<A
std::vector<ASStackUnpositionedLine> lines = collectChildrenIntoLines(items, style, sizeRange);
// Resolve the flexible lengths (https://www.w3.org/TR/css-flexbox-1/#resolve-flexible-lengths)
flexLinesAlongStackDimension(lines, style, sizeRange, parentSize, optimizedFlexing);
flexLinesAlongStackDimension(lines, style, concurrent, sizeRange, parentSize, optimizedFlexing);
// Calculate the cross size of each flex line (https://www.w3.org/TR/css-flexbox-1/#algo-cross-line)
computeLinesCrossSizeAndBaseline(lines, style, sizeRange);
// Handle 'align-content: stretch' (https://www.w3.org/TR/css-flexbox-1/#algo-line-stretch)
// Determine the used cross size of each item (https://www.w3.org/TR/css-flexbox-1/#algo-stretch)
stretchLinesAlongCrossDimension(lines, style, sizeRange, parentSize);
stretchLinesAlongCrossDimension(lines, style, concurrent, sizeRange, parentSize);
// Compute stack dimension sum of each line and the whole stack
CGFloat layoutStackDimensionSum = 0;