[iOS] Add scrollToOverflowEnabled prop to ScrollView

Libraries/Components/ScrollView/ScrollView.js

@@ -221,6 +221,12 @@ type IOSProps = $ReadOnly<{|
    * @platform ios
    */
   scrollIndicatorInsets?: ?EdgeInsetsProp,
+  /**
+   * When true, the scroll view can be programmatically scrolled beyond its
+   * content size. The default value is false.
+   * @platform ios
+   */
+  scrollToOverflowEnabled?: ?boolean,
   /**
    * When true, the scroll view scrolls to top when the status bar is tapped.
    * The default value is true.

React/Views/ScrollView/RCTScrollView.h

@@ -44,6 +44,7 @@
 @property (nonatomic, assign) NSTimeInterval scrollEventThrottle;
 @property (nonatomic, assign) BOOL centerContent;
 @property (nonatomic, copy) NSDictionary *maintainVisibleContentPosition;
+@property (nonatomic, assign) BOOL scrollToOverflowEnabled;
 @property (nonatomic, assign) int snapToInterval;
 @property (nonatomic, copy) NSArray<NSNumber *> *snapToOffsets;
 @property (nonatomic, assign) BOOL snapToStart;

React/Views/ScrollView/RCTScrollView.m

@@ -615,7 +615,7 @@ - (void)scrollToOffset:(CGPoint)offset animated:(BOOL)animated
                                 fmax(_scrollView.contentSize.height - _scrollView.bounds.size.height + _scrollView.contentInset.bottom + fmax(_scrollView.contentInset.top, 0), 0.01)); // Make width and height greater than 0
     // Ensure at least one scroll event will fire
     _allowNextScrollNoMatterWhat = YES;
-    if (!CGRectContainsPoint(maxRect, offset)) {
+    if (!CGRectContainsPoint(maxRect, offset) && !self.scrollToOverflowEnabled) {
       CGFloat x = fmax(offset.x, CGRectGetMinX(maxRect));
       x = fmin(x, CGRectGetMaxX(maxRect));
       CGFloat y = fmax(offset.y, CGRectGetMinY(maxRect));

React/Views/ScrollView/RCTScrollViewManager.m

@@ -83,6 +83,7 @@ - (UIView *)view
 RCT_EXPORT_VIEW_PROPERTY(zoomScale, CGFloat)
 RCT_EXPORT_VIEW_PROPERTY(contentInset, UIEdgeInsets)
 RCT_EXPORT_VIEW_PROPERTY(scrollIndicatorInsets, UIEdgeInsets)
+RCT_EXPORT_VIEW_PROPERTY(scrollToOverflowEnabled, BOOL)
 RCT_EXPORT_VIEW_PROPERTY(snapToInterval, int)
 RCT_EXPORT_VIEW_PROPERTY(snapToOffsets, NSArray<NSNumber *>)
 RCT_EXPORT_VIEW_PROPERTY(snapToStart, BOOL)