Dont measure single flex grow+shrink child

Reviewed By: gkassabli

Differential Revision: D4153133

fbshipit-source-id: 2333150a83857cc30078cc8d52761cbd00652830
This commit is contained in:
Emil Sjolander 2016-11-09 11:23:21 -08:00 committed by Facebook Github Bot
parent a731a23d91
commit a4a02f6b57
1 changed files with 52 additions and 31 deletions

View File

@ -286,7 +286,6 @@ static void _CSSNodeMarkDirty(const CSSNodeRef node) {
}
void CSSNodeSetMeasureFunc(const CSSNodeRef node, CSSMeasureFunc measureFunc) {
// You can always NULLify the measure function of a node.
if (measureFunc == NULL) {
node->measure = NULL;
} else {
@ -301,7 +300,8 @@ CSSMeasureFunc CSSNodeGetMeasureFunc(const CSSNodeRef node) {
void CSSNodeInsertChild(const CSSNodeRef node, const CSSNodeRef child, const uint32_t index) {
CSS_ASSERT(child->parent == NULL, "Child already has a parent, it must be removed first.");
CSS_ASSERT(node->measure == NULL, "Cannot add child: Nodes with measure functions cannot have children.");
CSS_ASSERT(node->measure == NULL,
"Cannot add child: Nodes with measure functions cannot have children.");
CSSNodeListInsert(&node->children, child, index);
child->parent = node;
_CSSNodeMarkDirty(node);
@ -1399,6 +1399,26 @@ static void layoutNodeImpl(const CSSNodeRef node,
const float availableInnerMainDim = isMainAxisRow ? availableInnerWidth : availableInnerHeight;
const float availableInnerCrossDim = isMainAxisRow ? availableInnerHeight : availableInnerWidth;
// If there is only one child with flexGrow + flexShrink it means we can set the
// computedFlexBasis to 0 instead of measuring and shrinking / flexing the child to exactly
// match the remaining space
CSSNodeRef singleFlexChild = NULL;
if ((isMainAxisRow && widthMeasureMode == CSSMeasureModeExactly) ||
(!isMainAxisRow && heightMeasureMode == CSSMeasureModeExactly)) {
for (uint32_t i = 0; i < childCount; i++) {
const CSSNodeRef child = CSSNodeGetChild(node, i);
if (singleFlexChild) {
if (isFlex(child)) {
// There is already a flexible child, abort.
singleFlexChild = NULL;
break;
}
} else if (CSSNodeStyleGetFlexGrow(child) > 0 && CSSNodeStyleGetFlexShrink(child) > 0) {
singleFlexChild = child;
}
}
}
// STEP 3: DETERMINE FLEX BASIS FOR EACH ITEM
for (uint32_t i = 0; i < childCount; i++) {
const CSSNodeRef child = CSSNodeListGet(node->children, i);
@ -1423,13 +1443,17 @@ static void layoutNodeImpl(const CSSNodeRef node,
currentAbsoluteChild = child;
child->nextChild = NULL;
} else {
computeChildFlexBasis(node,
child,
availableInnerWidth,
widthMeasureMode,
availableInnerHeight,
heightMeasureMode,
direction);
if (child == singleFlexChild) {
child->layout.computedFlexBasis = 0;
} else {
computeChildFlexBasis(node,
child,
availableInnerWidth,
widthMeasureMode,
availableInnerHeight,
heightMeasureMode,
direction);
}
}
}
@ -2165,17 +2189,17 @@ static inline bool newMeasureSizeIsStricterAndStillValid(CSSMeasureMode sizeMode
}
bool CSSNodeCanUseCachedMeasurement(const CSSMeasureMode widthMode,
const float width,
const CSSMeasureMode heightMode,
const float height,
const CSSMeasureMode lastWidthMode,
const float lastWidth,
const CSSMeasureMode lastHeightMode,
const float lastHeight,
const float lastComputedWidth,
const float lastComputedHeight,
const float marginRow,
const float marginColumn) {
const float width,
const CSSMeasureMode heightMode,
const float height,
const CSSMeasureMode lastWidthMode,
const float lastWidth,
const CSSMeasureMode lastHeightMode,
const float lastHeight,
const float lastComputedWidth,
const float lastComputedHeight,
const float marginRow,
const float marginColumn) {
if (lastComputedHeight < 0 || lastComputedWidth < 0) {
return false;
}
@ -2193,19 +2217,16 @@ bool CSSNodeCanUseCachedMeasurement(const CSSMeasureMode widthMode,
newMeasureSizeIsStricterAndStillValid(
widthMode, width - marginRow, lastWidthMode, lastWidth, lastComputedWidth);
const bool heightIsCompatible = hasSameHeightSpec ||
newSizeIsExactAndMatchesOldMeasuredSize(heightMode,
height - marginColumn,
lastComputedHeight) ||
oldSizeIsUnspecifiedAndStillFits(heightMode,
const bool heightIsCompatible =
hasSameHeightSpec || newSizeIsExactAndMatchesOldMeasuredSize(heightMode,
height - marginColumn,
lastHeightMode,
lastComputedHeight) ||
newMeasureSizeIsStricterAndStillValid(heightMode,
height - marginColumn,
lastHeightMode,
lastHeight,
lastComputedHeight);
oldSizeIsUnspecifiedAndStillFits(heightMode,
height - marginColumn,
lastHeightMode,
lastComputedHeight) ||
newMeasureSizeIsStricterAndStillValid(
heightMode, height - marginColumn, lastHeightMode, lastHeight, lastComputedHeight);
return widthIsCompatible && heightIsCompatible;
}