IssueTracker

No, it's just a simple application with a Screen A going to Screen B, and both are using the camera.

By adding some log info in the library side, the issue happens in the following steps when running the sample project provided in comment#1.

• Activity is launched and the 1st pair of CameraController and PreviewView is created. The CameraController is set to the PreviewView by PreviewView#setController.
• Press the thumbup button to create the 2nd pair of Camera CameraController and PreviewView.
• The 1st PreviewView will receive onDetachedFromWindow callback. It will call CameraController#clearPreviewSurface() and then ProcessCameraProvider#unbindAll() will be called.

All use cases are unbound so the camera is closed.

The following log is extracted from the attached log when the issue happens:

10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.lifecycle.LifecycleCameraRepository.suspendUseCases(LifecycleCameraRepository.java:438)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.lifecycle.LifecycleCameraRepository.setInactive(LifecycleCameraRepository.java:394)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.lifecycle.LifecycleCameraRepository.unbindAll(LifecycleCameraRepository.java:334)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.lifecycle.ProcessCameraProvider.unbindAll(ProcessCameraProvider.java:514)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.view.CameraController.clearPreviewSurface(CameraController.java:514)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.camera.view.PreviewView.onDetachedFromWindow(PreviewView.java:277)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.View.dispatchDetachedFromWindow(View.java:21358)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:4649)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:4641)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.ViewGroup.removeViewInternal(ViewGroup.java:6287)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.ViewGroup.removeViewInternal(ViewGroup.java:6258)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.ViewGroup.removeView(ViewGroup.java:6189)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.platform.AndroidComposeView.removeAndroidView(AndroidComposeView.android.kt:466)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.viewinterop.AndroidViewHolder$layoutNode$1$4.invoke(AndroidViewHolder.android.kt:254)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.viewinterop.AndroidViewHolder$layoutNode$1$4.invoke(AndroidViewHolder.android.kt:253)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.node.LayoutNode.detach$ui_release(LayoutNode.kt:370)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.node.LayoutNode.detach$ui_release(LayoutNode.kt:381)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.node.LayoutNode.detach$ui_release(LayoutNode.kt:381)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.node.LayoutNode.removeAt$ui_release(LayoutNode.kt:257)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.node.UiApplier.remove(UiApplier.android.kt:36)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.runtime.ComposerImpl$realizeMovement$1.invoke(Composer.kt:2903)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.runtime.ComposerImpl$realizeMovement$1.invoke(Composer.kt:2903)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.runtime.CompositionImpl.applyChanges(Composition.kt:629)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:479)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:416)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.platform.AndroidUiFrameClock$withFrameNanos$2$callback$1.doFrame(AndroidUiFrameClock.android.kt:34)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.platform.AndroidUiDispatcher.performFrameDispatch(AndroidUiDispatcher.android.kt:109)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.platform.AndroidUiDispatcher.access$performFrameDispatch(AndroidUiDispatcher.android.kt:41)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at androidx.compose.ui.platform.AndroidUiDispatcher$dispatchCallback$1.doFrame(AndroidUiDispatcher.android.kt:69)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.Choreographer$CallbackRecord.run(Choreographer.java:997)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.Choreographer.doCallbacks(Choreographer.java:797)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.Choreographer.doFrame(Choreographer.java:728)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:984)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.os.Handler.handleCallback(Handler.java:883)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.os.Handler.dispatchMessage(Handler.java:100)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.os.Looper.loop(Looper.java:237)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at android.app.ActivityThread.main(ActivityThread.java:8167)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at java.lang.reflect.Method.invoke(Native Method)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:496)
10-31 00:49:59.042 10102  2039  2039 D XXXXX   : 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1100)

The issue disappears if resetting CameraController when new PreviewView is created.

var previewView : PreviewView? = null

@Composable
fun CameraPreview(flashEnabled: Boolean, modifier: Modifier = Modifier) {
    val lifecycleOwner = LocalLifecycleOwner.current
    val context = LocalContext.current

    // Resets CameraController from the previous PreviewView
    previewView?.controller = null

    val controller = remember {
        LifecycleCameraController(context).apply {
            cameraSelector = CameraSelector.Builder()
                .requireLensFacing(CameraSelector.LENS_FACING_BACK)
                .build()
        }
    }

    DisposableEffect(true) {
        Log.d("XXXXX","DisposableEffect++ lifecycleOwner: " + lifecycleOwner)
        controller.bindToLifecycle(lifecycleOwner)
        Log.d("XXXXX","DisposableEffect++")
        onDispose {
        }
    }

    controller.enableTorch(flashEnabled)

    previewView = PreviewView(context)
    previewView!!.controller = controller

    AndroidView(
        factory = { ctx -> previewView!!
        },
        modifier = modifier
    )
}

The solution in the camera-view side will be only unbinding the use cases created by the CameraController instead of directly calling ProcessorCameraProvider#unbindAll().

Attach the bugreport of the log mentioned in comment#4.

The issue is fixed by https://android-review.googlesource.com/1813958 and will be included in CameraX's next release. Update the status to be Fixed.