fix: issues with presenting owned modals from foreign ones

[kkafar]

Description

Basically this is another edition of the issue #1829 (handled by #1912).
The issue comes down to the fact, that our ScreenStack is not aware of all modal view controllers being in presentation,
but this time it is not aware of third-party modal view controllers (I've named them "foreign" modals in opposite to "owned" modals).

This PR is not a comprehensive solution but rather just a patch aiming at fixing one particular interaction reported in #2048.

I've left verbose code comments explaining the issue and suggesting solution in the source code, including:

  // TODO: Find general way to manage owned and foreign modal view controllers and refactor this code. Consider building
  // model first (data structue, attempting to be aware of all modals in presentation and some text-like algorithm for
  // computing required operations).

Closes #2048
Closes #2085

Changes

Trigger dissmisal of foreign modal if it is presented above changeRoot modal (last modal that is to stay on stack after the updates).

Test code and steps to reproduce

Test2048 in TestsExample & FabricTestExample.

Checklist

• Included code example that can be used to test this change
• Ensured that CI passes

[kkafar]

TODO: Checkout whether I need to handle RNSModalScreenComponent (or whatever its name is)

[tboba]

On first sight, it looks good to me! Just left some small comments 🎉

[kkafar]

Thanks for review. I'll wait with merging till I get response on #2048.

[WoLewicki]

Some spelling checks.

[WoLewicki]

controller

[WoLewicki]

structure

[WoLewicki]

might be the second case

[WoLewicki]

Hopefully it did not destroy any scenarios where some code was aware of the problem and did its own workarounds for the issue. We should find a complete solution for the case ASAP I think.

[kkafar]

Hopefully it did not destroy any scenarios where some code was aware of the problem and did its own workarounds for the issue.

Yeah, I can see it happen but 🤷🏻 In the end, we do not promise any stability of behaviour / API of native side code.

We should find a complete solution for the case ASAP I think.

My idea revolves around implementing something in the shape of Levenshtein distance algorithm, however it's problematic because at the level of screen stack we do not have accurate information about what modals are in presentation (there might be modals presented from other stack, or foreign modals*). Even if we computed this dynamically, e.g. by registering each presented modal in RNSScreenStackManager, which is shared between various RNSScreenStack instances, there arises issue of modals, that are not presented under separate UITransitionView 😅 How do we find such third-party modals? <-- this is open question for me. We can discuss this on some screens meeting.

I'll fix typos in follow up sometime soon

[hirbod]

I believe that this change, or RNS in general, causes problems with hot reload when another ViewController is present.
GitHub Issue

It works fine and detaches RNS Modals on reload (pressing R), but keeps the RNS Modal attachted when another UIViewController is on top of it upon reload.

[kkafar]

Hey @hirbod, would you mind opening a dedicated issue for the case you described? (🤞🏻 for reproduction). I'm sure we will be able to look into it.

[hirbod]

@kkafar I already found a solution

I patched RNSScreenStack and changed invalidate

// updated this
- (void)invalidate {
    _invalidated = YES;
    [self dismissAllPresentedViewControllersFrom:_controller completion:^{
        // Ensure presented modals are removed and the controller is detached from its parent
        [_presentedModals removeAllObjects];
        [_controller willMoveToParentViewController:nil];
        [_controller removeFromParentViewController];
    }];
}

- (void)dismissOnReload {
    dispatch_async(dispatch_get_main_queue(), ^{
        [self invalidate];
    });
}

// added this
- (void)dismissAllPresentedViewControllersFrom:(UIViewController *)viewController completion:(void (^)(void))completion {
    if (viewController.presentedViewController) {
        [viewController.presentedViewController dismissViewControllerAnimated:NO completion:^{
            [self dismissAllPresentedViewControllersFrom:viewController completion:completion];
        }];
    } else {
        completion();
    }
}

[hirbod]

I'll open a PR

[kkafar]

Excellent, thank you!

[hirbod]

#2175