android studio 在后台使用相机

Question

I'm new to the Android studio and I was trying to make the camera work in the background. I just want the camera to get the feed activity of it but when I'm trying to open the app it just automatically stops. The camera is usually working fine if it's in the MainActivity but when I transfer it to my camera service the app automatically stops when I open.

public class CameraService extends Service implements CameraBridgeViewBase.CvCameraViewListener2{

private static final String TAG = "MainActivity";
private JavaCameraView mOpenCvCameraView;
private Mat mRgba;
public CameraService(){

}
@Override
public IBinder onBind(Intent intent) {

    throw new UnsupportedOperationException("Not yet implemented");
}

private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
    @Override
    public void onManagerConnected(int status){
        switch (status) {
            case LoaderCallbackInterface.SUCCESS:{
                Log.i(TAG, "OpenCV loaded successfully");
                mOpenCvCameraView.enableView();
            }
            break;
            default:{
                super.onManagerConnected(status);
            }
            break;
        }
    }
};


@Override
public void onCreate() {

    mOpenCvCameraView = (JavaCameraView) mOpenCvCameraView.findViewById(R.id.javacameraview);
    mOpenCvCameraView.setVisibility(SurfaceView.VISIBLE);
    mOpenCvCameraView.setCvCameraViewListener(this);
    mOpenCvCameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_FRONT);
    Toast.makeText(this, "The new Service was Created", Toast.LENGTH_LONG).show();

}



private void setContentView(int activity_main) {
}

@Override
public void onStart(Intent intent, int startId) {


    Toast.makeText(this, " Service Started", Toast.LENGTH_LONG).show();

}

@Override
public void onDestroy() {
    Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
    super.onDestroy();
    if (mOpenCvCameraView != null)
        mOpenCvCameraView.disableView();

}

@Override
public void onCameraViewStarted(int width, int height) {
    mRgba = new Mat(height, width, CvType.CV_8UC4);
}

@Override
public void onCameraViewStopped() {
    mRgba.release();
}

@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
    return inputFrame.rgba();
}
}

can someone give me some tips or pinpoint my problem?

Answer 1

Google's Android Pie update came with a new feature that prevents apps from running in the background from using the camera. This feature ensures that you don't live in fear of malicious apps (that remain active in the background when your screen is turned off) capturing potentially unwanted scenes of you or your loved ones without authorization.

error in your code: you are using an unassigned object to find the id

if you are doing it for illegal purposes, don't do this -this type of problem is not liked by the StackOverflow community.