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fix(android): no camera devices on app start #3575

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Merged
merged 1 commit into from
Jul 14, 2025
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fix(android): no camera devices on app start #3575

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11 changes: 8 additions & 3 deletions package/android/src/main/java/com/mrousavy/camera/react/CameraDevicesManager.kt
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Original file line number Diff line number Diff line change
Expand Up @@ -59,9 +59,8 @@ class CameraDevicesManager(private val reactContext: ReactApplicationContext) :

override fun getName(): String = TAG

override fun initialize() {
super.initialize()
cameraManager.registerAvailabilityCallback(callback, null)
// Init cameraProvider + manager as early as possible
init {
Comment on lines +62 to +63
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@n-kulic n-kulic Sep 5, 2025 •
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@hannojg @mrousavy Just noting that in this PR, sendAvailableDevicesChangedEvent() was indirectly moved into init, which is causing crashes on hot restart because js bridge isn't ready yet. We opened a follow-up PR to fix this by moving event back to initialize():

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@mrousavy mrousavy Sep 6, 2025

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uhm - does that not effectively just revert our changes? @hannojg can you review/confirm?

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@n-kulic n-kulic Sep 6, 2025 •
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@mrousavy Not a full revert, early init of native part (cameraProvider/extensionsManager) is still kept in init.

The only change is moving sendAvailableDevicesChangedEvent() back into initialize(), because that's where it's safe to call getJSModule.

The problem with previous approach is that getJSModule was being called from init (by sendAvailableDevicesChangedEvent) before JS bridge was ready. You can see that here:

  private ReactApplicationContext createReactContext(...) {
    ...
    // CameraDevicesManager.init triggers here
    NativeModuleRegistry nativeModuleRegistry = processPackages(reactContext, mPackages);

   // JS bridge initialization starts here
    CatalystInstanceImpl.Builder catalystInstanceBuilder = new CatalystInstanceImpl.Builder()
    ...
    
    // Key point: calling getJSModule before this will throw IllegalStateException,
    // which is what currently happens in CameraDevicesManager.init.sendAvailableDevicesChangedEvent.getJSModule
    reactContext.initializeWithInstance(catalystInstance);

So why it works on cold start?

Short answer: timing/race condition.

Long answer: cameraProvider and extensionsManger initialize asynchronously by coroutine. On cold start coroutine usually schedules slightly later, so JS bridge is ready by the time sendAvailableDevicesChangedEvent() runs. Hot restart exposes this timing issue.

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@mrousavy mrousavy Sep 8, 2025

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Got it thanks!

coroutineScope.launch {
try {
Log.i(TAG, "Initializing ProcessCameraProvider...")
Expand All @@ -76,6 +75,12 @@ class CameraDevicesManager(private val reactContext: ReactApplicationContext) :
}
}

// Note: initialize() will be called after getConstants on new arch!
override fun initialize() {
super.initialize()
cameraManager.registerAvailabilityCallback(callback, null)
}

override fun invalidate() {
cameraManager.unregisterAvailabilityCallback(callback)
super.invalidate()
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