我正在制作的应用程序，从firebase远程命令前置摄像头的图像。应用程序工作正常，无需用户交互就可以拍照，但当应用程序关闭或转到前台时，应用程序开始给出错误，无法连接到相机服务。只要应用程序打开它就可以捕捉图像。
我运行前台服务通知，其中工作，但仍然相同的相机失败错误，无法拍照。

try {

                    Log.d("kkkk", "Preparing to take photo");

                    Camera.CameraInfo cameraInfo = new Camera.CameraInfo();

                    int frontCamera = cam;
                    //int backCamera=0;

                    Camera.getCameraInfo(frontCamera, cameraInfo);

                    try {
                        camera = Camera.open(frontCamera);
                    } catch (RuntimeException e) {
                        Log.d("kkkk", "Camera not available: " + e.getMessage());
                        camera = null;
//                        takePicture(0);
                    }
                    try {
                        if (null == camera) {
                            Log.d("kkkk", "Could not get camera instance");
                        } else {
                            Log.d("kkkk", "Got the camera, creating the dummy surface texture");
                            try {
                                camera.setPreviewTexture(new SurfaceTexture(0));
                                camera.startPreview();
                            } catch (Exception e) {
                                Log.d("kkkk", "Could not set the surface preview texture");
                                e.printStackTrace();
                            }
                            camera.takePicture(null, null, new Camera.PictureCallback() {

                                @Override
                                public void onPictureTaken(byte[] data, Camera camera) {

                                    Log.d("kkkk", "clicked");


                                    // Encode the byte array into a base64 string
//                                    String imageString = android.util.Base64.encodeToString(imageBytes, android.util.Base64.DEFAULT);
//                                    Log.d("error200", imageString);

                                    FirebaseStorage storage = FirebaseStorage.getInstance();

                                    StorageReference storageRef = storage.getReference();

                                    String path = "images/"+username.toLowerCase()+device.replace(" ","");

                                    StorageReference imageRef = storageRef.child(path);

                                    Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length); // Replace this with your bitmap image
                                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                                    bitmap.compress(Bitmap.CompressFormat.JPEG, 10, baos);
                                    byte[] data0 = baos.toByteArray();

                                    UploadTask uploadTask = imageRef.putBytes(data0);
                                    uploadTask.addOnFailureListener(new OnFailureListener() {
                                        @Override
                                        public void onFailure(@NonNull Exception exception) {
                                            // Handle unsuccessful uploads
                                            Log.d("pic","fail"+exception.getMessage());
                                        }
                                    }).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                                        @Override
                                        public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                                            // Handle successful uploads
                                            Log.d("pic","done");
                                        }
                                    });

                                    camera.release();

                                }
                            });
                        }
                    } catch (Exception e) {
                        camera.release();
                    }

                } catch (Exception e) {
                    Log.d("errorData", e.getMessage());
                }

onDestroy方法我释放了摄像机，但仍然出现相同的错误。

@Override
    public void onDestroy() {
        super.onDestroy();

        if (camera != null) {
            camera.stopPreview();
            camera.release();
            camera = null;
        }```