Unregister the activity lifecycle callbacks when disposing the camera

[kmorkos]

Fix crash referenced in flutter/flutter#18348

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[kmorkos]

I signed it

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CLAs look good, thanks!

[maral]

@kmorkos I have just checked your fix by changing pubspec.yaml as you mentioned in flutter/flutter#18348, and it fixed the first error, however introduced another one. I wonder if it has something to do with the CameraPreview I am using. There is no way to dispose that 😢.

This happens after I leave the camera page and go back to previous page. Immediately the error occurs.

Should I file a new issue?

This is the stacktrace:

I/RequestThread-0(17244): Received jpeg.
I/RequestThread-0(17244): Producing jpeg buffer...
I/flutter (17244): Picture saved to /data/user/0/cz.codit.stromysvobody/app_flutter/Pictures/strom_71.jpg
W/LegacyRequestMapper(17244): convertRequestMetadata - control.awbRegions setting is not supported, ignoring value
W/LegacyRequestMapper(17244): Only received metering rectangles with weight 0.
W/LegacyRequestMapper(17244): Only received metering rectangles with weight 0.
I/zygote64(17244): Do full code cache collection, code=249KB, data=171KB
I/zygote64(17244): After code cache collection, code=239KB, data=144KB
I/SimplePermission(17244): Requesting permission : android.permission.ACCESS_FINE_LOCATION
I/RequestQueue(17244): Repeating capture request cancelled.
E/BufferQueueProducer(17244): [SurfaceTexture-1-17244-2] cancelBuffer: BufferQueue has been abandoned
I/chatty  (17244): uid=10167(u0_a167) Binder:17244_2 identical 1 line
E/BufferQueueProducer(17244): [SurfaceTexture-1-17244-2] cancelBuffer: BufferQueue has been abandoned
I/SimplePermission(17244): Requesting permission result : true
E/libc    (17244): Access denied finding property "persist.camera.cfa.packagelist"
I/CameraManager(17244): Using legacy camera HAL.
E/libc    (17244): Access denied finding property "camera.hal1.packagelist"
I/flutter (17244): ##### DISPOSING CAMERA PAGE (my own message)
E/GLConsumer(17244): [SurfaceTexture-0-17244-0] setDefaultBufferSize: GLConsumer is abandoned!
D/AndroidRuntime(17244): Shutting down VM
E/AndroidRuntime(17244): FATAL EXCEPTION: main
E/AndroidRuntime(17244): Process: cz.codit.stromysvobody, PID: 17244
E/AndroidRuntime(17244): java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.Surface android.media.ImageReader.getSurface()' on a null object reference
E/AndroidRuntime(17244): 	at io.flutter.plugins.camera.CameraPlugin$Camera.startPreview(CameraPlugin.java:676)
E/AndroidRuntime(17244): 	at io.flutter.plugins.camera.CameraPlugin$Camera.access$2000(CameraPlugin.java:243)
E/AndroidRuntime(17244): 	at io.flutter.plugins.camera.CameraPlugin$Camera$3.onOpened(CameraPlugin.java:443)
E/AndroidRuntime(17244): 	at android.hardware.camera2.impl.CameraDeviceImpl$1.run(CameraDeviceImpl.java:143)
E/AndroidRuntime(17244): 	at android.os.Handler.handleCallback(Handler.java:789)
E/AndroidRuntime(17244): 	at android.os.Handler.dispatchMessage(Handler.java:98)
E/AndroidRuntime(17244): 	at android.os.Looper.loop(Looper.java:172)
E/AndroidRuntime(17244): 	at android.app.ActivityThread.main(ActivityThread.java:6637)
E/AndroidRuntime(17244): 	at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(17244): 	at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
E/AndroidRuntime(17244): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)

[maral]

Interesting, it works now and no error. Who knows why, this is all magic to me.
EDIT: It happened again, but it happens not too often, randomly.

[mvwaran]

When it will be fixed? I'm still facing the issue and i'm using camera plugin 0.2.3 version.

[kmorkos]

It was never merged in... I'm not sure how to get a reviewer to look at it.

[kmorkos]

@kroikie I saw you were assigned to some other pull requests. Perhaps you can take a look at this or tag somebody else who can?

[bparrishMines]

Hi @kmorkos

Everything looks good except I think you should re-register the activitylifecyclecallbacks in the 'initialize' method. I think an error would occur if one camera was disposed and then another was initialized without the activitylifecyclecallback being registered.

[kmorkos]

@bparrishMines thanks for checking this out. That makes sense, just made that change!

[bparrishMines]

Merged! I created a PR to bump the version on pub.
@maral Are you still having crashes from this PR? Based on the camera plugin code, I think it may be caused by a separate bug.

[kmorkos]

@bparrishMines thanks! Can you push the update to pub please? 😄

[bparrishMines]

@kmorkos Sorry about that! Published!