[iOS] onPageSelected not fire when init first

[LeLuyen]

On iOS, the onPageSelected event is not fired when the AnimatedPagerView is initialized for the first time with the default page (initialPage={0}).

This behavior was working as expected before, but after upgrading to the latest version, the initial page selection event is no longer emitted.

Environment
react-native-pager-view: 8.0.1 ~ 8.0.3
React Native: 0.84.1
New Architecture (Fabric): Enabled
Platform: iOS

[troZee]

Hello 👋
Could you tell me what exact version is affected? Does 8.0.1 work for you?

[LeLuyen]

Version 8.0.0 works with React Native 0.78.2.

Versions 8.0.1 through 8.0.3 do not work with React Native 0.84.1.

I'm currently using version 8.0.1 with React Native 0.84.1, and it's not working.

[LeLuyen]

I found a workaround for this issue.

Adding the following code to RNCPagerViewComponentView.mm resolves the problem:

if (_pagerViewProvider.currentPage == -1) {
     _pagerViewProvider.currentPage = newScreenProps.initialPage;
      **if (newScreenProps.initialPage >= 0) {
         dispatch_async(dispatch_get_main_queue(), ^{
           [self onPageSelectedWithPosition:newScreenProps.initialPage];
         });
      }**
}

[hungtd97]

Check this PR https://github.com/callstack/react-native-pager-view/pull/1070/changes
No clue why it hasn't been merged yet.

[troZee]

@hungtd97
This is the reason:
#1070 (review)