카메라 라이브 미리보기가 카메라 스위치에서 멈춤

맞춤형 카메라 앱을 만들고 있습니다. 내가 직면 한 문제는 전면 카메라와 후면 카메라 사이를 전환 할 때 카메라 미리보기가 정지된다는 것입니다. 전화로 전면 또는 후면 카메라로 활동을 시작할 때

boolean opened = safeCameraOpenInView(view, Camera.CameraInfo.CAMERA_FACING_BACK)

조각의 OnCreateView 메서드에서 두 카메라 모두 시작시 예상대로 표시됩니다. 스위치 버튼의 클릭 리스너에서 동일한 메서드를 호출하자마자 카메라가 즉시 정지됩니다.

이것은 여기에있는 질문에 따라 모든 코드가 사용자 지정 클래스 대신 동일한 조각 내에있는 새로운 구현입니다. 사용자 지정 클래스 카메라 라이브 미리보기가 카메라 스위치에서 고정 되지만 결과는 정확히 동일합니다. 나는 그것을 새로운 카메라에 바인딩하기 위해 표면 뷰로 뭔가를해야한다고 확신하지만, 이것을하는 방법을 잃어 버렸다. 아무도 포인터가 있습니까?

내 활동 :

public class Camera2ActivityFragment extends Fragment {

    // Native camera.
    private Camera mCamera;


    // View to display the camera output.
    private CameraPreview mPreview;

    // Reference to the containing view.
    private View mCameraView;

    /**
     * Default empty constructor.
     */
    public Camera2ActivityFragment(){
        super();
    }

    /**
     * Static factory method
     * @param sectionNumber
     * @return
     */
    public static Camera2ActivityFragment newInstance(int sectionNumber) {
        Camera2ActivityFragment fragment = new Camera2ActivityFragment();
        //Bundle args = new Bundle();
        //args.putInt(ARG_SECTION_NUMBER, sectionNumber);
        //fragment.setArguments(args);
        return fragment;
    }

    /**
     * OnCreateView fragment override
     * @param inflater
     * @param container
     * @param savedInstanceState
     * @return
     */
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_camera2, container, false);
        boolean opened = safeCameraOpenInView(view, Camera.CameraInfo.CAMERA_FACING_BACK);

        if(opened == false){
            Log.d("CameraGuide","Error, Camera failed to open");
            return view;
        }

        // Trap the capture button.
        Button captureButton = (Button) view.findViewById(R.id.btnCameraStart);
        captureButton.setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        // get an image from the camera
                        mCamera.takePicture(null, null, mPicture);
                    }
                }
        );

        Button switchCameraButton = (Button) view.findViewById(R.id.btnSwitchCamera);
        switchCameraButton.setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        safeCameraOpenInView(getView(), Camera.CameraInfo.CAMERA_FACING_FRONT); //ISSUE OCCURS HERE!
                    }
                }
        );

        return view;
    }

    /**
     * Recommended "safe" way to open the camera.
     * @param view
     * @return
     */
    private boolean safeCameraOpenInView(View view, int camID) {
        boolean qOpened = false;
        releaseCameraAndPreview();
        //mCamera = getCameraInstance(Camera.CameraInfo.CAMERA_FACING_BACK);
        mCamera = getCameraInstance(camID);
        mCameraView = view;
        qOpened = (mCamera != null);

        if(qOpened == true){
            mPreview = new CameraPreview(getActivity().getBaseContext(), mCamera,view);
            FrameLayout preview = (FrameLayout) view.findViewById(R.id.camera_view);
            preview.addView(mPreview);
            mPreview.startCameraPreview();
        }
        return qOpened;
    }

    /**
     * Safe method for getting a camera instance.
     * @return
     */
    public static Camera getCameraInstance(int camID){
        Camera c = null;
        try {
            c = Camera.open(camID); // attempt to get a Camera instance
        }
        catch (Exception e){
            e.printStackTrace();
        }
        return c; // returns null if camera is unavailable
    }

    @Override
    public void onPause() {
        super.onPause();
    }

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

    /**
     * Clear any existing preview / camera.
     */
    private void releaseCameraAndPreview() {

        if (mCamera != null) {
            mCamera.stopPreview();
            mCamera.release();
            mCamera = null;
        }
        if(mPreview != null){
            mPreview.destroyDrawingCache();
            mPreview.mCamera = null;
        }
    }

    /**
     * Surface on which the camera projects it's capture results. This is derived both from Google's docs and the
     * excellent StackOverflow answer provided below.
     *
     * Reference / Credit: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
     */
    class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

        // SurfaceHolder
        private SurfaceHolder mHolder;

        // Our Camera.
        private Camera mCamera;

        // Parent Context.
        private Context mContext;

        // Camera Sizing (For rotation, orientation changes)
        private Camera.Size mPreviewSize;

        // List of supported preview sizes
        private List<Camera.Size> mSupportedPreviewSizes;

        // Flash modes supported by this camera
        private List<String> mSupportedFlashModes;

        // View holding this camera.
        private View mCameraView;

        public CameraPreview(Context context, Camera camera, View cameraView) {
            super(context);

            // Capture the context
            mCameraView = cameraView;
            mContext = context;
            setCamera(camera);

            // Install a SurfaceHolder.Callback so we get notified when the
            // underlying surface is created and destroyed.
            mHolder = getHolder();
            mHolder.addCallback(this);
            mHolder.setKeepScreenOn(true);
            // deprecated setting, but required on Android versions prior to 3.0
            mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

        /**
         * Begin the preview of the camera input.
         */
        public void startCameraPreview()
        {
            try{
                mCamera.setPreviewDisplay(mHolder);
                mCamera.startPreview();
            }
            catch(Exception e){
                e.printStackTrace();
            }
        }

        /**
         * Extract supported preview and flash modes from the camera.
         * @param camera
         */
        private void setCamera(Camera camera)
        {
            // Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
            mCamera = camera;
            mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
            mSupportedFlashModes = mCamera.getParameters().getSupportedFlashModes();

            // Set the camera to Auto Flash mode.
            if (mSupportedFlashModes != null && mSupportedFlashModes.contains(Camera.Parameters.FLASH_MODE_AUTO)){
                Camera.Parameters parameters = mCamera.getParameters();
                parameters.setFlashMode(Camera.Parameters.FLASH_MODE_AUTO);
                parameters.setRotation(90);
                //parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
                mCamera.setParameters(parameters);
                mCamera.setDisplayOrientation(90);
            }

            requestLayout();
        }

        /**
         * The Surface has been created, now tell the camera where to draw the preview.
         * @param holder
         */
        public void surfaceCreated(SurfaceHolder holder) {
            try {
                mCamera.setPreviewDisplay(holder);

                //mCam = Camera.open();
                //mCam.setPreviewDisplay(holder);

            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        /**
         * Dispose of the camera preview.
         * @param holder
         */
        public void surfaceDestroyed(SurfaceHolder holder) {
            if (mCamera != null){
                mCamera.stopPreview();
            }
        }

        /**
         * React to surface changed events
         * @param holder
         * @param format
         * @param w
         * @param h
         */
        public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {

            //Log.e(TAG, "surfaceChanged => w=" + w + ", h=" + h);
            // If your preview can change or rotate, take care of those events here.
            // Make sure to stop the preview before resizing or reformatting it.
            if (mHolder.getSurface() == null){
                // preview surface does not exist
                return;
            }

            // stop preview before making changes
            try {
                mCamera.stopPreview();
                //mCamera.release();
            } catch (Exception e){
                // ignore: tried to stop a non-existent preview
            }

            // set preview size and make any resize, rotate or reformatting changes here
            // start preview with new settings
            try {
                Camera.Parameters parameters = mCamera.getParameters();
                parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
                parameters.setRotation(90);
                parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
                mCamera.setParameters(parameters);
                mCamera.setDisplayOrientation(90);
                mCamera.setPreviewDisplay(mHolder);
                mCamera.enableShutterSound(true);
                mCamera.startPreview();

            } catch (Exception e){
                //Log.d(TAG, "Error starting camera preview: " + e.getMessage());
            }
        }

        /**
         * Calculate the measurements of the layout
         * @param widthMeasureSpec
         * @param heightMeasureSpec
         */
        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
        {
            /*
            // Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
            final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
            final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
            setMeasuredDimension(width, height);

            if (mSupportedPreviewSizes != null){
                mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
            }
            */
            final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
            final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);

            if (mSupportedPreviewSizes != null) {
                mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
            }

            float ratio;
            if(mPreviewSize.height >= mPreviewSize.width)
                ratio = (float) mPreviewSize.height / (float) mPreviewSize.width;
            else
                ratio = (float) mPreviewSize.width / (float) mPreviewSize.height;

            // One of these methods should be used, second method squishes preview slightly
            setMeasuredDimension(width, (int) (width * ratio));
//        setMeasuredDimension((int) (width * ratio), height);
        }

        /**
         * Update the layout based on rotation and orientation changes.
         * @param changed
         * @param left
         * @param top
         * @param right
         * @param bottom
         */
        @Override
        protected void onLayout(boolean changed, int left, int top, int right, int bottom)
        {
            // Source: https://stackoverflow.com/questions/7942378/android-camera-will-not-work-startpreview-fails
            if (changed) {
                final int width = right - left;
                final int height = bottom - top;

                int previewWidth = width;
                int previewHeight = height;

                if (mPreviewSize != null){
                    Display display = ((WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();

                    switch (display.getRotation())
                    {
                        case Surface.ROTATION_0:
                            previewWidth = mPreviewSize.height;
                            previewHeight = mPreviewSize.width;
                            mCamera.setDisplayOrientation(90);
                            break;
                        case Surface.ROTATION_90:
                            previewWidth = mPreviewSize.width;
                            previewHeight = mPreviewSize.height;
                            break;
                        case Surface.ROTATION_180:
                            previewWidth = mPreviewSize.height;
                            previewHeight = mPreviewSize.width;
                            break;
                        case Surface.ROTATION_270:
                            previewWidth = mPreviewSize.width;
                            previewHeight = mPreviewSize.height;
                            mCamera.setDisplayOrientation(180);
                            break;
                    }
                }

                final int scaledChildHeight = previewHeight * width / previewWidth;
                mCameraView.layout(0, height - scaledChildHeight, width, height);
            }
        }

        /**
         *
         * @param sizes
         * @param width
         * @param height
         * @return
         */
        private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int width, int height)
        {
            final double ASPECT_TOLERANCE = 0.1;
            double targetRatio = (double) height / width;

            if (sizes == null)
                return null;

            Camera.Size optimalSize = null;
            double minDiff = Double.MAX_VALUE;

            int targetHeight = height;

            for (Camera.Size size : sizes) {
                double ratio = (double) size.height / size.width;
                if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
                    continue;

                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }

            if (optimalSize == null) {
                minDiff = Double.MAX_VALUE;
                for (Camera.Size size : sizes) {
                    if (Math.abs(size.height - targetHeight) < minDiff) {
                        optimalSize = size;
                        minDiff = Math.abs(size.height - targetHeight);
                    }
                }
            }

            return optimalSize;
        }
    }

    /**
     * Picture Callback for handling a picture capture and saving it out to a file.
     */
    private Camera.PictureCallback mPicture = new Camera.PictureCallback() {

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

            File pictureFile = getOutputMediaFile();
            if (pictureFile == null){
                Toast.makeText(getActivity(), "Image retrieval failed.", Toast.LENGTH_SHORT)
                        .show();
                return;
            }

            try {
                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();

            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    };

    /**
     * Used to return the camera File output.
     * @return
     */
    private File getOutputMediaFile(){

        File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES), "Pocket Booth");

        if (! mediaStorageDir.exists()){
            if (! mediaStorageDir.mkdirs()){
                Log.d("Camera Guide", "Required media storage does not exist");
                return null;
            }
        }

        // Create a media file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        File mediaFile;
        mediaFile = new File(mediaStorageDir.getPath() + File.separator +
                "IMG_"+ timeStamp + ".jpg");

        //DialogHelper.showDialog( "Success!","Your picture has been saved!",getActivity());

        return mediaFile;
    }
}