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cameraSource.release() throws null pointer exception if detector is null

See original GitHub issue

java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.vision.Detector.release()' on a null object reference

According to [https://developers.google.com/android/reference/com/google/android/gms/vision/CameraSource.html#release()](Android Documentation) release method completely shuts down this camera source and releases the resources of the underlying detector. But sometimes detector is null and this method throws exception.

Would it not be better to handle camerasource and detector resource separately in that case?

Issue Analytics

State:
Created 7 years ago
Comments:8 (1 by maintainers)

Top GitHub Comments

8reactions

LucianIacobcommented, Feb 13, 2018

@Davehp44 we solved this in a way like:

if (mCameraSource != null) {
     try {
         mCameraSource.release();
     } catch (NullPointerException ignored) {  }
     mCameraSource = null;
}

And then for starting camera:

if (cameraSource == null) {
     releaseCamera();
     return;
}

mCameraSource = cameraSource;
mCameraSource.start(mSurfaceView.getHolder());

4reactions

vpdsouzacommented, Jun 2, 2017

Nope, I debugged the code to make sure the release is only called once and it is. But the moment I restart it I get this:

Exception thrown from receiver. java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.vision.Detector.receiveFrame(com.google.android.gms.vision.Frame)' on a null object reference at com.imbills.mobile.barcode.ui.camera.CameraSource$FrameProcessingRunnable.run(CameraSource.java:1205)

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