From 54d3e83bbfdb26281e08d54f32324b734d2e8889 Mon Sep 17 00:00:00 2001
From: Valentin Shergin <shergin@fb.com>
Date: Fri, 3 Feb 2017 15:13:36 -0800
Subject: [PATCH] Fixed crash in RCTScrollView on iOS 8

Reviewed By: javache

Differential Revision: D4508906

fbshipit-source-id: 08955f338879f708d35f4784e858a92b542e8661
---
 React/Views/RCTScrollView.m | 10 ++++++----
 React/Views/RCTView.m       | 12 ++++++------
 React/Views/UIView+React.m  | 26 +++++++++++++-------------
 3 files changed, 25 insertions(+), 23 deletions(-)

diff --git a/React/Views/RCTScrollView.m b/React/Views/RCTScrollView.m
index 3115b9142..4f5fe0735 100644
--- a/React/Views/RCTScrollView.m
+++ b/React/Views/RCTScrollView.m
@@ -160,10 +160,12 @@ RCT_NOT_IMPLEMENTED(- (instancetype)init)
   if ((self = [super initWithFrame:frame])) {
     [self.panGestureRecognizer addTarget:self action:@selector(handleCustomPan:)];
 
-    // We intentionaly force `UIScrollView`s `semanticContentAttribute` to `LTR` here
-    // because this attribute affects a position of vertical scrollbar; we don't want this
-    // scrollbar flip because we also flip it with whole `UIScrollView` flip.
-    self.semanticContentAttribute = UISemanticContentAttributeForceLeftToRight;
+    if ([self respondsToSelector:@selector(setSemanticContentAttribute:)]) {
+      // We intentionaly force `UIScrollView`s `semanticContentAttribute` to `LTR` here
+      // because this attribute affects a position of vertical scrollbar; we don't want this
+      // scrollbar flip because we also flip it with whole `UIScrollView` flip.
+      self.semanticContentAttribute = UISemanticContentAttributeForceLeftToRight;
+    }
   }
   return self;
 }
diff --git a/React/Views/RCTView.m b/React/Views/RCTView.m
index ba7f84342..21d7a71bc 100644
--- a/React/Views/RCTView.m
+++ b/React/Views/RCTView.m
@@ -128,12 +128,12 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:unused)
 {
   _reactLayoutDirection = layoutDirection;
 
-#if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_9_0
-  self.semanticContentAttribute =
-    layoutDirection == UIUserInterfaceLayoutDirectionLeftToRight ?
-      UISemanticContentAttributeForceLeftToRight :
-      UISemanticContentAttributeForceRightToLeft;
-#endif
+  if ([self respondsToSelector:@selector(setSemanticContentAttribute:)]) {
+    self.semanticContentAttribute =
+      layoutDirection == UIUserInterfaceLayoutDirectionLeftToRight ?
+        UISemanticContentAttributeForceLeftToRight :
+        UISemanticContentAttributeForceRightToLeft;
+  }
 }
 
 - (NSString *)accessibilityLabel
diff --git a/React/Views/UIView+React.m b/React/Views/UIView+React.m
index 84217a805..43502719f 100644
--- a/React/Views/UIView+React.m
+++ b/React/Views/UIView+React.m
@@ -89,23 +89,23 @@
 
 - (UIUserInterfaceLayoutDirection)reactLayoutDirection
 {
-#if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_9_0
-  return [UIView userInterfaceLayoutDirectionForSemanticContentAttribute:self.semanticContentAttribute];
-#else
-  return [objc_getAssociatedObject(self, @selector(reactLayoutDirection)) integerValue];
-#endif
+  if ([self respondsToSelector:@selector(semanticContentAttribute)]) {
+    return [UIView userInterfaceLayoutDirectionForSemanticContentAttribute:self.semanticContentAttribute];
+  } else {
+    return [objc_getAssociatedObject(self, @selector(reactLayoutDirection)) integerValue];
+  }
 }
 
 - (void)setReactLayoutDirection:(UIUserInterfaceLayoutDirection)layoutDirection
 {
-#if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_9_0
-  self.semanticContentAttribute =
-    layoutDirection == UIUserInterfaceLayoutDirectionLeftToRight ?
-      UISemanticContentAttributeForceLeftToRight :
-      UISemanticContentAttributeForceRightToLeft;
-#else
-  objc_setAssociatedObject(self, @selector(reactLayoutDirection), @(layoutDirection), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-#endif
+  if ([self respondsToSelector:@selector(setSemanticContentAttribute:)]) {
+    self.semanticContentAttribute =
+      layoutDirection == UIUserInterfaceLayoutDirectionLeftToRight ?
+        UISemanticContentAttributeForceLeftToRight :
+        UISemanticContentAttributeForceRightToLeft;
+  } else {
+    objc_setAssociatedObject(self, @selector(reactLayoutDirection), @(layoutDirection), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+  }
 }
 
 - (NSInteger)reactZIndex