Make RCTRefreshControl not dependent on order of setting properties

Summary: With the Cxx bridge, properties are not guaranteed to be set it any order (and furthermore, they should not be). RCTRefreshControl previously had its title set first, and would crash otherwise. This fixes that.

Reviewed By: mhorowitz

Differential Revision: D4580253

fbshipit-source-id: 39baecceb8b67c6a851c08ba9cabbf4dc99359cb

React/Views/RCTRefreshControl.m

@@ -14,6 +14,8 @@
 @implementation RCTRefreshControl {
   BOOL _isInitialRender;
   BOOL _currentRefreshingState;
+  NSString *_title;
+  UIColor *_titleColor;
 }
 
 - (instancetype)init
@@ -86,23 +88,33 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
 
 - (NSString *)title
 {
-  return self.attributedTitle.string;
+  return _title;
 }
 
 - (void)setTitle:(NSString *)title
 {
-  NSRange range = NSMakeRange(0, self.attributedTitle.length);
-  NSDictionary *attrs = [self.attributedTitle attributesAtIndex:0 effectiveRange: &range];
-  self.attributedTitle = [[NSAttributedString alloc] initWithString:title attributes:attrs];
+  _title = title;
+  [self _updateTitle];
 }
 
 - (void)setTitleColor:(UIColor *)color
 {
-  NSRange range = NSMakeRange(0, self.attributedTitle.length);
-  NSDictionary *attrs = [self.attributedTitle attributesAtIndex:0 effectiveRange: &range];
-  NSMutableDictionary *attrsMutable = [attrs mutableCopy];
-  [attrsMutable setObject:color forKey:NSForegroundColorAttributeName];
-  self.attributedTitle = [[NSAttributedString alloc] initWithString:self.attributedTitle.string attributes:attrsMutable];
+  _titleColor = color;
+  [self _updateTitle];
+}
+
+- (void)_updateTitle
+{
+  if (!_title) {
+    return;
+  }
+
+  NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
+  if (_titleColor) {
+    attributes[NSForegroundColorAttributeName] = _titleColor;
+  }
+
+  self.attributedTitle = [[NSAttributedString alloc] initWithString:_title attributes:attributes];
 }
 
 - (void)setRefreshing:(BOOL)refreshing