LargeHeader stays small after pop/goBack/swipe gesture on iOS 14+

[hirbod]

Hi,

I just upgraded to Expo SDK 39 and before of that, I had never an issue navigating to a child screen (from LargeHeader to small header). When I go back now, it stays smalls instead of growing back to large.

What has changed and is this something known?

[hirbod]

This looks like it has nothing to do with SDK 39, its an issue with iOS 14. It works on iOS 13.
Here is a video @WoLewicki https://streamable.com/x4vo01

The same code on iOS 13 will grow the large header back to its original size.

[WoLewicki]

Yeah, I can spot problems with this. It looks like some kind of bug because it doesn't happen in the Settings of your phone. Am I right?

[hirbod]

@WoLewicki you are right, works great everywhere else in the system.

[ArekChr]

The same here 👍

[WoLewicki]

Does this behavior appear only while using ScrollView?

[hirbod]

For me, it happens when using ScrollView and FlatList

[julian-baumann]

Maybe this is related: iOS 14 Large title collapse when app run firstly.

I experience this issue too, when I start the app or scroll to the top, navigate and go back on iOS 14.

[WoLewicki]

Can you check if #670 fixes the issue and does not introduce any new issues?

[grahammendick]

I’ve got the same problem on my Navigation router (@WoLewicki your fix didn’t work for me).

I’ve worked out a fix but we need to tweak the RCTScrollContentView class in React Native. We must ensure that updateContentOffsetIfNeeded first runs after the ScrollView is moved to the window. So we prevent it running inside reactSetFrame if there’s no window yet and get it to run from didMoveToWindow instead.

Here’s the fixed RCTScrollContentView. Can you check it works for you, please? You can open your project in XCode and paste this code into RCTScrollContentView

@implementation RCTScrollContentView

- (void)didMoveToWindow
{
    [super didMoveToWindow];
    RCTScrollView *scrollView = (RCTScrollView *)self.superview.superview;
    [scrollView updateContentOffsetIfNeeded];
}

- (void)reactSetFrame:(CGRect)frame
{
  [super reactSetFrame:frame];

  RCTScrollView *scrollView = (RCTScrollView *)self.superview.superview;

  if (!scrollView || !self.window) {
    return;
  }

  RCTAssert([scrollView isKindOfClass:[RCTScrollView class]], @"Unexpected view hierarchy of RCTScrollView component.");

  [scrollView updateContentOffsetIfNeeded];
}

@end