Fix RCTRefreshControl jumping

Reviewed By: shergin

Differential Revision: D6470066

fbshipit-source-id: 44fb03c264d98af61dccfa0146690fd49ee9f2ab

Author: sophiebits

Diff for: React/Views/RCTRefreshControl.m

@@ -14,6 +14,7 @@
 @implementation RCTRefreshControl {
   BOOL _isInitialRender;
   BOOL _currentRefreshingState;
+  BOOL _refreshingProgrammatically;
   NSString *_title;
   UIColor *_titleColor;
 }
@@ -48,8 +49,9 @@ - (void)layoutSubviews
   _isInitialRender = false;
 }
 
-- (void)beginRefreshing
+- (void)beginRefreshingProgrammatically
 {
+  _refreshingProgrammatically = YES;
   // When using begin refreshing we need to adjust the ScrollView content offset manually.
   UIScrollView *scrollView = (UIScrollView *)self.superview;
   CGPoint offset = {scrollView.contentOffset.x, scrollView.contentOffset.y - self.frame.size.height};
@@ -66,12 +68,12 @@ - (void)beginRefreshing
                      }];
 }
 
-- (void)endRefreshing
+- (void)endRefreshingProgrammatically
 {
   // The contentOffset of the scrollview MUST be greater than 0 before calling
   // endRefreshing otherwise the next pull to refresh will not work properly.
   UIScrollView *scrollView = (UIScrollView *)self.superview;
-  if (scrollView.contentOffset.y < 0) {
+  if (_refreshingProgrammatically && scrollView.contentOffset.y < 0) {
     CGPoint offset = {scrollView.contentOffset.x, 0};
     [UIView animateWithDuration:0.25
                           delay:0
@@ -124,17 +126,18 @@ - (void)setRefreshing:(BOOL)refreshing
 
     if (refreshing) {
       if (!_isInitialRender) {
-        [self beginRefreshing];
+        [self beginRefreshingProgrammatically];
       }
     } else {
-      [self endRefreshing];
+      [self endRefreshingProgrammatically];
     }
   }
 }
 
 - (void)refreshControlValueChanged
 {
   _currentRefreshingState = super.refreshing;
+  _refreshingProgrammatically = NO;
 
   if (_onRefresh) {
     _onRefresh(nil);