[iOS] ModalHostViewController not properly dismissed if presenting another VC
Personne n'a encore pris cette issue.
- Langage dominant
- C++
- Étoiles
- 127k
- Forks
- 25.3k
- Merge moyen
- 1 j 23 h
- PR mergées (30 j)
- 4
Description
Description
In our brownfield application, we have a scenario where we can open a login flow from the RN Modal component. The login flow shows an iOS system view controller with a webview. At the same time, the dialog is getting closed. The result of these two actions happening roughly at the same time is that: 1) the login VC gets dismissed, while the RCTModalHostViewController is still present as a top-level VC, but without any UI. It is intercepting all touches and preventing further usage of the app.
Here is the view hierarchy:
I've done some investigation and found that this is due to the following RN code:
- (void)dismissViewController:(UIViewController *)modalViewController
animated:(BOOL)animated
completion:(void (^)(void))completion
{
[modalViewController dismissViewControllerAnimated:animated completion:completion];
}
Basically the modal VC is trying to dismiss itself. However, the dismissViewControllerAnimated:completion: method has two modes:
- When given VC is the top presented on, it dismisses itself from its parent
- When given VC is presenting another VC, it is dismissing that VC instead, but it stays presented itself.
Relevant docs from iOS API:
The presenting view controller is responsible for dismissing the view controller it presented. If you call this method on the presented view controller itself, UIKit asks the presenting view controller to handle the dismissal.
Fix for that would be to make the code dismiss the same whether modal VC is presenting another VC or not. A simple way would be to replace:
[modalViewController dismissViewControllerAnimated:animated completion:completion];
with
[modalViewController.presentingViewController dismissViewControllerAnimated:animated completion:completion];
Note: the reproducer uses react-native-image-picker library to show another VC, but in our brownfield app, we use our VC. The type of VC does not really matter, as the important part is that it's presented on top of the modal VC that will be dismissed before the 2nd VC gets dismissed.
Steps to reproduce
- Download & run the reproducer repo: https://github.com/mdjastrzebski/rn-repro-stale-modal-vc-blocks-touches
- Press the "Open Modal" button
- The modal should open, press "Open Photo Library"
- The system Photo Picker should slide in briefly and get dismissed
- After you are back to the initial VC you cannot make any more touch actions, as an invisible RCTModalHostViewController is still present (see view hierarchy screenshot)
You may need to repeat this a few times, but you should be able to trigger the issue. In our brownfield app, we have 100% repro, but in the contrived example, it only occurs sometimes.
https://github.com/user-attachments/assets/0b2e63d6-4301-4045-b108-a8bfeccc5b3c
React Native Version
0.83.0
Affected Platforms
Runtime - iOS
Output of npx @react-native-community/cli info
System:
OS: macOS 26.1
CPU: (11) arm64 Apple M3 Pro
Memory: 266.56 MB / 36.00 GB
Shell:
version: "5.9"
path: /bin/zsh
Binaries:
Node:
version: 22.17.1
path: /Users/mdj/.nvm/versions/node/v22.17.1/bin/node
Yarn:
version: 1.22.22
path: /Users/mdj/.nvm/versions/node/v22.17.1/bin/yarn
npm:
version: 10.9.2
path: /Users/mdj/.nvm/versions/node/v22.17.1/bin/npm
Watchman:
version: 2025.07.28.00
path: /opt/homebrew/bin/watchman
Managers:
CocoaPods:
version: 1.16.2
path: /Users/mdj/.rbenv/shims/pod
SDKs:
iOS SDK:
Platforms:
- DriverKit 25.0
- iOS 26.0
- macOS 26.0
- tvOS 26.0
- visionOS 26.0
- watchOS 26.0
Android SDK:
API Levels:
- "35"
- "36"
Build Tools:
- 35.0.0
- 36.0.0
System Images:
- android-35 | Google Play ARM 64 v8a
- android-36 | Google Play ARM 64 v8a
Android NDK: Not Found
IDEs:
Android Studio: 2025.2 AI-252.25557.131.2521.14432022
Xcode:
version: 26.0.1/17A400
path: /usr/bin/xcodebuild
Languages:
Java:
version: 17.0.16
path: /usr/bin/javac
Ruby:
version: 3.4.5
path: /Users/mdj/.rbenv/shims/ruby
npmPackages:
"@react-native-community/cli":
installed: 20.0.0
wanted: 20.0.0
react:
installed: 19.2.0
wanted: 19.2.0
react-native:
installed: 0.83.0
wanted: 0.83.0
react-native-macos: Not Found
npmGlobalPackages:
"*react-native*": Not Found
Android:
hermesEnabled: true
newArchEnabled: true
iOS:
hermesEnabled: true
newArchEnabled: true
Stacktrace or Logs
n/a
MANDATORY Reproducer
https://github.com/mdjastrzebski/rn-repro-stale-modal-vc-blocks-touches
Screenshots and Videos
No response
Guide de contribution
Ouvrir le guide de contribution
Par où commencer
- Lisez l'issue en entier, puis le guide de contribution du projet.
- Signalez en commentaire que vous la prenez — cela évite que deux personnes fassent le même travail.
- Forkez le dépôt et travaillez sur une branche.
- Ouvrez une pull request qui référence le numéro de l'issue.
Piste de recherche
Commencez dans packages/react-native/React/Fabric/Mounting/ComponentViews/Modal/RCTModalHostViewComponentView.mm, au niveau de dismissViewController:. Exécutez le reproducer lié rn-repro-stale-modal-vc-blocks-touches et vérifiez le chemin de dismissal lorsqu’un autre view controller est présenté. C’est terminé lorsque le modal host est entièrement dismissed et n’intercepte plus les touches après la fermeture du photo picker ou d’un autre controller.
Rédigé par le modèle d'indexation à partir du texte de l'issue.
Évaluation
- Stack technique
- ios, objective-c, react-native
- Domaine
- mobile-dev
- Type d'issue
- Bug
- Difficulté
- 3/5
- Temps estimé
- 1-2 jours
- Activité
- Calme
- Clarté
- Clairement spécifiée
- Accessibilité débutants
- 68/100