Re-render views when direction changes

Summary:
This is required for D5874536, wherein I'll be introducing direction-aware props for borders.

When a view's border changes due to a direction update, only the frames of its children update. Therefore, only the children `UIView`s get a chance to be re-rendered. This is incorrect because the view that's had its borders changed also needs to re-render. So, I keep a track of the layout direction in a property on all shadow views. Then, when I update that prop within `applyLayoutNode`, I push shadow views into the `viewsWithNewFrames` set.

Reviewed By: mmmulani

Differential Revision: D5944488

fbshipit-source-id: 3f23e9973f3555612920703cdb6cec38e6360d2d

Libraries/Text/RCTShadowText.m

@@ -38,7 +38,7 @@ static CGFloat const kAutoSizeGranularity       = 0.001f;
   CGFloat _cachedTextStorageWidthMode;
   NSAttributedString *_cachedAttributedString;
   CGFloat _effectiveLetterSpacing;
-  UIUserInterfaceLayoutDirection _cachedEffectiveLayoutDirection;
+  UIUserInterfaceLayoutDirection _cachedLayoutDirection;
 }
 
 static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, float height, YGMeasureMode heightMode)
@@ -72,7 +72,7 @@ static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, f
     _fontSizeMultiplier = 1.0;
     _textAlign = NSTextAlignmentNatural;
     _writingDirection = NSWritingDirectionNatural;
-    _cachedEffectiveLayoutDirection = UIUserInterfaceLayoutDirectionLeftToRight;
+    _cachedLayoutDirection = UIUserInterfaceLayoutDirectionLeftToRight;
 
     YGNodeSetMeasureFunc(self.yogaNode, RCTMeasure);
 
@@ -198,7 +198,7 @@ static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, f
       _cachedTextStorage &&
       (width == _cachedTextStorageWidth || (isnan(width) && isnan(_cachedTextStorageWidth))) &&
       widthMode == _cachedTextStorageWidthMode &&
-      _cachedEffectiveLayoutDirection == self.effectiveLayoutDirection
+      _cachedLayoutDirection == self.layoutDirection
   ) {
     return _cachedTextStorage;
   }
@@ -272,12 +272,12 @@ static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, f
   if (
       ![self isTextDirty] &&
       _cachedAttributedString &&
-      _cachedEffectiveLayoutDirection == self.effectiveLayoutDirection
+      _cachedLayoutDirection == self.layoutDirection
   ) {
     return _cachedAttributedString;
   }
 
-  _cachedEffectiveLayoutDirection = self.effectiveLayoutDirection;
+  _cachedLayoutDirection = self.layoutDirection;
 
   if (_fontSize && !isnan(_fontSize)) {
     fontSize = @(_fontSize);
@@ -419,7 +419,7 @@ static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, f
   // Text alignment
   NSTextAlignment textAlign = _textAlign;
   if (textAlign == NSTextAlignmentRight || textAlign == NSTextAlignmentLeft) {
-    if (_cachedEffectiveLayoutDirection == UIUserInterfaceLayoutDirectionRightToLeft) {
+    if (_cachedLayoutDirection == UIUserInterfaceLayoutDirectionRightToLeft) {
       if (textAlign == NSTextAlignmentRight) {
         textAlign = NSTextAlignmentLeft;
       } else {

React/Modules/RCTUIManager.m

@@ -494,7 +494,7 @@ static NSDictionary *deviceOrientationEventBody(UIDeviceOrientation orientation)
       reactTags[index] = shadowView.reactTag;
       frameDataArray[index++] = (RCTFrameData){
         shadowView.frame,
-        shadowView.effectiveLayoutDirection,
+        shadowView.layoutDirection,
         shadowView.isNewView,
         shadowView.superview.isNewView,
         shadowView.isHidden,

React/Views/RCTScrollContentShadowView.m

@@ -27,7 +27,7 @@
        absolutePosition:(CGPoint)absolutePosition
 {
   // Call super method if LTR layout is enforced.
-  if (self.effectiveLayoutDirection == UIUserInterfaceLayoutDirectionLeftToRight) {
+  if (self.layoutDirection == UIUserInterfaceLayoutDirectionLeftToRight) {
     [super applyLayoutNode:node
          viewsWithNewFrame:viewsWithNewFrame
           absolutePosition:absolutePosition];

React/Views/RCTShadowView.h

@@ -84,9 +84,10 @@ typedef void (^RCTApplierBlock)(NSDictionary<NSNumber *, UIView *> *viewRegistry
 @property (nonatomic, assign, getter=isHidden) BOOL hidden;
 
 /**
- * Computed layout direction for the view backed to Yoga node value.
+ * Layout direction for the view as computed in applyLayoutNode.
  */
-@property (nonatomic, assign, readonly) UIUserInterfaceLayoutDirection effectiveLayoutDirection;
+
+@property (nonatomic, assign, readonly) UIUserInterfaceLayoutDirection layoutDirection;
 
 /**
  * Position and dimensions.
@@ -187,6 +188,11 @@ typedef void (^RCTApplierBlock)(NSDictionary<NSNumber *, UIView *> *viewRegistry
  */
 @property (nonatomic, assign) CGSize intrinsicContentSize;
 
+/**
+ * Return the layout direction stored in the Yoga node that backs this view.
+ */
+- (UIUserInterfaceLayoutDirection)getLayoutDirectionFromYogaNode;
+
 /**
  * Calculate property changes that need to be propagated to the view.
  * The applierBlocks set contains RCTApplierBlock functions that must be applied

React/Views/RCTShadowView.m

@@ -204,8 +204,11 @@ static void RCTProcessMetaPropsBorder(const YGValue metaProps[META_PROP_COUNT],
     RCTRoundPixelValue(absoluteBottomRight.y - absoluteTopLeft.y)
   }};
 
-  if (!CGRectEqualToRect(frame, _frame)) {
+  UIUserInterfaceLayoutDirection updatedLayoutDirection = [self getLayoutDirectionFromYogaNode];
+
+  if (!CGRectEqualToRect(frame, _frame) || _layoutDirection != updatedLayoutDirection) {
     _frame = frame;
+    _layoutDirection = updatedLayoutDirection;
     [viewsWithNewFrame addObject:self];
   }
 
@@ -493,7 +496,7 @@ static void RCTProcessMetaPropsBorder(const YGValue metaProps[META_PROP_COUNT],
 
 // Layout Direction
 
-- (UIUserInterfaceLayoutDirection)effectiveLayoutDirection {
+- (UIUserInterfaceLayoutDirection)getLayoutDirectionFromYogaNode {
   // Even if `YGNodeLayoutGetDirection` can return `YGDirectionInherit` here, it actually means
   // that Yoga will use LTR layout for the view (even if layout process is not finished yet).
   return YGNodeLayoutGetDirection(_yogaNode) == YGDirectionRTL ? UIUserInterfaceLayoutDirectionRightToLeft : UIUserInterfaceLayoutDirectionLeftToRight;