How to take screenshot for Android Surface view

I'm try to implement Take a Screenshot form my camera Surface view through code. I able to do of those things, however the screenshot always appears black. Here is the Code. i have searched many links and implement my code. but still screenshot appear black. how to resolve this. please guide me. thanks

public class Cam_View extends Activity implements SurfaceHolder.Callback {

    protected static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 0;
    private SurfaceView SurView;
    private SurfaceHolder camHolder;
    private boolean previewRunning;
    final Context context = this;
    public static Camera camera = null;
    private RelativeLayout CamView;
    private Bitmap inputBMP = null, bmp, bmp1;
    private ImageView mImage,camera_image;

    @SuppressWarnings("deprecation")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.testscreenshot);

        CamView = (RelativeLayout) findViewById(R.id.camview);//RELATIVELAYOUT OR 
                                                              //ANY LAYOUT OF YOUR XML

        SurView = (SurfaceView)findViewById(R.id.sview);//SURFACEVIEW FOR THE PREVIEW 
                                                        //OF THE CAMERA FEED
        camHolder = SurView.getHolder();                           //NEEDED FOR THE PREVIEW
        camHolder.addCallback(this);                               //NEEDED FOR THE PREVIEW
        camHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);//NEEDED FOR THE PREVIEW
        camera_image = (ImageView) findViewById(R.id.camera_image);//NEEDED FOR THE PREVIEW

        Button btn = (Button) findViewById(R.id.button1); //THE BUTTON FOR TAKING PICTURE

        btn.setOnClickListener(new OnClickListener() {    //THE BUTTON CODE
            public void onClick(View v) {
                 camera.takePicture(null, null, mPicture);//TAKING THE PICTURE
                                                         //THE mPicture IS CALLED 
                                                         //WHICH IS THE LAST METHOD(SEE BELOW)
            }
        });
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,//NEEDED FOR THE PREVIEW
        int height) {
        if(previewRunning) {
            camera.stopPreview();
        }
        Camera.Parameters camParams = camera.getParameters();
        Camera.Size size = camParams.getSupportedPreviewSizes().get(0);
        camParams.setPreviewSize(size.width, size.height);
        camera.setParameters(camParams);
        try {
            camera.setPreviewDisplay(holder);
            camera.startPreview();
            previewRunning=true;
        } catch(IOException e) {
            e.printStackTrace();
        }
    }

    public void surfaceCreated(SurfaceHolder holder) {                  //NEEDED FOR THE PREVIEW
        try {
            camera=Camera.open();
        } catch(Exception e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            finish();
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {             //NEEDED FOR THE PREVIEW
        camera.stopPreview();
        camera.release();
        camera=null;
    }

    public void TakeScreenshot(){    //THIS METHOD TAKES A SCREENSHOT AND SAVES IT AS .jpg


     Random num = new Random();
        int nu=num.nextInt(1000); //PRODUCING A RANDOM NUMBER FOR FILE NAME
        CamView.setDrawingCacheEnabled(true); //CamView OR THE NAME OF YOUR LAYOUR
        CamView.buildDrawingCache(true);
        Bitmap bmp = Bitmap.createBitmap(CamView.getDrawingCache());
        CamView.setDrawingCacheEnabled(false); // clear drawing cache
        ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
        bmp.compress(CompressFormat.JPEG, 100, bos); 
        byte[] bitmapdata = bos.toByteArray();
        ByteArrayInputStream fis = new ByteArrayInputStream(bitmapdata);

        String picId=String.valueOf(nu);
        String myfile="Ghost"+picId+".jpeg";

        File dir_image = new  File(Environment.getExternalStorageDirectory()+//<---
                        File.separator+"Ultimate Entity Detector");          //<---
        dir_image.mkdirs();                                                  //<---
        //^IN THESE 3 LINES YOU SET THE FOLDER PATH/NAME . HERE I CHOOSE TO SAVE
        //THE FILE IN THE SD CARD IN THE FOLDER "Ultimate Entity Detector"

        try {
            File tmpFile = new File(dir_image,myfile); 
            FileOutputStream fos = new FileOutputStream(tmpFile);

            byte[] buf = new byte[1024];
            int len;
            while ((len = fis.read(buf)) > 0) {
                fos.write(buf, 0, len);
            }
            fis.close();
            fos.close();
            Toast.makeText(getApplicationContext(),
                           "The file is saved at :SD/Ultimate Entity Detector",Toast.LENGTH_LONG).show();
            bmp1 = null;
            camera_image.setImageBitmap(bmp1); //RESETING THE PREVIEW
            camera.startPreview();             //RESETING THE PREVIEW
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private PictureCallback mPicture = new PictureCallback() {   //THIS METHOD AND THE METHOD BELOW
                                 //CONVERT THE CAPTURED IMAGE IN A JPG FILE AND SAVE IT

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

            File dir_image2 = new  File(Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate Entity Detector");
            dir_image2.mkdirs();  //AGAIN CHOOSING FOLDER FOR THE PICTURE(WHICH IS LIKE A SURFACEVIEW
                                  //SCREENSHOT)

            File tmpFile = new File(dir_image2,"TempGhost.jpg"); //MAKING A FILE IN THE PATH
                            //dir_image2(SEE RIGHT ABOVE) AND NAMING IT "TempGhost.jpg" OR ANYTHING ELSE
            try { //SAVING
                FileOutputStream fos = new FileOutputStream(tmpFile);
                fos.write(data);
                fos.close();
                //grabImage();
            } catch (FileNotFoundException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            } catch (IOException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            }

            String path = (Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate EntityDetector"+
                                                File.separator+"TempGhost.jpg");//<---

            BitmapFactory.Options options = new BitmapFactory.Options();//<---
                options.inPreferredConfig = Bitmap.Config.ARGB_8888;//<---
            bmp1 = BitmapFactory.decodeFile(path, options);//<---     *********(SEE BELOW)
            //THE LINES ABOVE READ THE FILE WE SAVED BEFORE AND CONVERT IT INTO A BitMap
            camera_image.setImageBitmap(bmp1); //SETTING THE BitMap AS IMAGE IN AN IMAGEVIEW(SOMETHING
                                        //LIKE A BACKGROUNG FOR THE LAYOUT)

            tmpFile.delete();
            TakeScreenshot();//CALLING THIS METHOD TO TAKE A SCREENSHOT
            //********* THAT LINE MIGHT CAUSE A CRASH ON SOME PHONES (LIKE XPERIA T)<----(SEE HERE)
            //IF THAT HAPPENDS USE THE LINE "bmp1 =decodeFile(tmpFile);" WITH THE METHOD BELOW

        }
    };

    public Bitmap decodeFile(File f) {  //FUNCTION BY Arshad Parwez
        Bitmap b = null;
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;

            FileInputStream fis = new FileInputStream(f);
            BitmapFactory.decodeStream(fis, null, o);
            fis.close();
            int IMAGE_MAX_SIZE = 1000;
            int scale = 1;
            if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) {
                scale = (int) Math.pow(
                        2,
                        (int) Math.round(Math.log(IMAGE_MAX_SIZE
                                / (double) Math.max(o.outHeight, o.outWidth))
                                / Math.log(0.5)));
            }

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            fis = new FileInputStream(f);
            b = BitmapFactory.decodeStream(fis, null, o2);
            fis.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return b;
    }
}

i have tesed your code. this i my screenshot.

this is screenshot my mobile screen shot.. home button is a screenshot button.

once button clicked. that screenshot will be black background

updated coding:

public class Cam_View extends Activity implements SurfaceHolder.Callback {

    protected static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 0;
    private SurfaceView SurView;
    private SurfaceHolder camHolder;
    private boolean previewRunning;
    final Context context = this;
    public static Camera camera = null;
    private RelativeLayout CamView;
    private Bitmap inputBMP = null, bmp, bmp1;
    private ImageView mImage,camera_image;


    @SuppressWarnings("deprecation")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.testscreenshot);

        CamView = (RelativeLayout) findViewById(R.id.camview);//RELATIVELAYOUT OR 
                                                              //ANY LAYOUT OF YOUR XML

        SurView = (SurfaceView)findViewById(R.id.sview);//SURFACEVIEW FOR THE PREVIEW 
                                                        //OF THE CAMERA FEED
        camHolder = SurView.getHolder();                           //NEEDED FOR THE PREVIEW
        camHolder.addCallback(this);                               //NEEDED FOR THE PREVIEW
        camHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);//NEEDED FOR THE PREVIEW
        camera_image = (ImageView) findViewById(R.id.camera_image);//NEEDED FOR THE PREVIEW

        Button btn = (Button) findViewById(R.id.button1); //THE BUTTON FOR TAKING PICTURE

        btn.setOnClickListener(new OnClickListener() {    //THE BUTTON CODE
            public void onClick(View v) {
            camera.takePicture(null, null, mPicture);//TAKING THE PICTURE
                                                         //THE mPicture IS CALLED 
                                                         //WHICH IS THE LAST METHOD(SEE BELOW)

            }

        });
    }

    public Bitmap screenShot(View view) {
        Bitmap bitmap = Bitmap.createBitmap(view.getWidth(),
                view.getHeight(), Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        view.draw(canvas);
        return bitmap;
    }

    private void openScreenshot(File imageFile) {
        Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        Uri uri = Uri.fromFile(imageFile);
        intent.setDataAndType(uri, "image/*");
        startActivity(intent);
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,//NEEDED FOR THE PREVIEW
        int height) {
        if(previewRunning) {
            camera.stopPreview();
        }
        Camera.Parameters camParams = camera.getParameters();
        Camera.Size size = camParams.getSupportedPreviewSizes().get(0);
        camParams.setPreviewSize(size.width, size.height);
        camera.setParameters(camParams);
        try {
            camera.setPreviewDisplay(holder);
            camera.startPreview();
            previewRunning=true;
        } catch(IOException e) {
            e.printStackTrace();
        }
    }

    public void surfaceCreated(SurfaceHolder holder) {                  //NEEDED FOR THE PREVIEW
        try {
            camera=Camera.open();
        } catch(Exception e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            finish();
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {             //NEEDED FOR THE PREVIEW
        camera.stopPreview();
        camera.release();
        camera=null;
    }

    public void TakeScreenshot(){    //THIS METHOD TAKES A SCREENSHOT AND SAVES IT AS .jpg

        CamView.setDrawingCacheEnabled(true);
        CamView.buildDrawingCache(true);

                        Bitmap b = Bitmap.createBitmap(CamView.getDrawingCache());
                        System.out.println("b====================="+b);
                        CamView.setDrawingCacheEnabled(false);


                        //Save bitmap to ur sdcard

                        File mFolder = new File( Environment.getExternalStorageDirectory().toString()+ "/xxx");
                        File mCapture = new File( mFolder.getAbsolutePath()+ "/Captured");

                        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SSS");
                        String dateString = formatter.format(new java.util.Date());

                        String fileName = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SSS'_xxx.jpg'").format(new Date());
                        File imgFile = new File(mCapture.getAbsolutePath(), fileName);

                        String extr = Environment.getExternalStorageDirectory().toString() +   File.separator + "xxx/Captured";

                        FileOutputStream fos = null;
                        try {
                            if (!mFolder.exists()) {
                                mFolder.mkdir();
                            }
                            if (!mCapture.exists()) {
                                mCapture.mkdir();
                            }
                            if (!imgFile.exists()) {
                                imgFile.createNewFile();
                            }
                            fos = new FileOutputStream(imgFile);
                            b.compress(Bitmap.CompressFormat.PNG, 100, fos);
                            fos.flush();
                            fos.close();
                            MediaStore.Images.Media.insertImage(Cam_View.this.getContentResolver(), b, "Screen", "screen");
                        }catch (FileNotFoundException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        } catch (Exception e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }



                        final Intent shareIntent = new Intent(Intent.ACTION_SEND);
                        shareIntent.setType("image/jpg");
                        final File photoFile = new File(extr,fileName);
                        shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(photoFile));
                        startActivity(Intent.createChooser(shareIntent, "Share image using"));


    }

    private PictureCallback mPicture = new PictureCallback() {   //THIS METHOD AND THE METHOD BELOW
                                 //CONVERT THE CAPTURED IMAGE IN A JPG FILE AND SAVE IT

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

            File dir_image2 = new  File(Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate Entity Detector");
            dir_image2.mkdirs();  //AGAIN CHOOSING FOLDER FOR THE PICTURE(WHICH IS LIKE A SURFACEVIEW
                                  //SCREENSHOT)

            File tmpFile = new File(dir_image2,"TempGhost.jpg"); //MAKING A FILE IN THE PATH
                            //dir_image2(SEE RIGHT ABOVE) AND NAMING IT "TempGhost.jpg" OR ANYTHING ELSE
            try { //SAVING
                FileOutputStream fos = new FileOutputStream(tmpFile);
                fos.write(data);
                fos.close();
                //grabImage();
            } catch (FileNotFoundException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            } catch (IOException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            }

            String path = (Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate EntityDetector"+
                                                File.separator+"TempGhost.jpg");//<---

            BitmapFactory.Options options = new BitmapFactory.Options();//<---
                options.inPreferredConfig = Bitmap.Config.ARGB_8888;//<---
            bmp1 = BitmapFactory.decodeFile(path, options);//<---     *********(SEE BELOW)
            //THE LINES ABOVE READ THE FILE WE SAVED BEFORE AND CONVERT IT INTO A BitMap
            camera_image.setImageBitmap(bmp1); //SETTING THE BitMap AS IMAGE IN AN IMAGEVIEW(SOMETHING
                                        //LIKE A BACKGROUNG FOR THE LAYOUT)

            tmpFile.delete();
            TakeScreenshot();//CALLING THIS METHOD TO TAKE A SCREENSHOT
            //********* THAT LINE MIGHT CAUSE A CRASH ON SOME PHONES (LIKE XPERIA T)<----(SEE HERE)
            //IF THAT HAPPENDS USE THE LINE "bmp1 =decodeFile(tmpFile);" WITH THE METHOD BELOW

        }
    };

    public Bitmap decodeFile(File f) {  //FUNCTION BY Arshad Parwez
        Bitmap b = null;
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;

            FileInputStream fis = new FileInputStream(f);
            BitmapFactory.decodeStream(fis, null, o);
            fis.close();
            int IMAGE_MAX_SIZE = 1000;
            int scale = 1;
            if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) {
                scale = (int) Math.pow(
                        2,
                        (int) Math.round(Math.log(IMAGE_MAX_SIZE
                                / (double) Math.max(o.outHeight, o.outWidth))
                                / Math.log(0.5)));
            }

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            fis = new FileInputStream(f);
            b = BitmapFactory.decodeStream(fis, null, o2);
            fis.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return b;
    }
}

mContentView.setDrawingCacheEnabled(true);
mContentView.buildDrawingCache(true);

                Bitmap b = Bitmap.createBitmap(mContentView.getDrawingCache());
                mContentView.setDrawingCacheEnabled(false);


                //Save bitmap to ur sdcard

                File mFolder = new File( Environment.getExternalStorageDirectory().toString()+ "/xxx");
                File mCapture = new File( mFolder.getAbsolutePath()+ "/Captured");

                SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SSS");
                String dateString = formatter.format(new java.util.Date());

                String fileName = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SSS'_xxx.jpg'").format(new Date());
                File imgFile = new File(mCapture.getAbsolutePath(), fileName);

                String extr = Environment.getExternalStorageDirectory().toString() +   File.separator + "xxx/Captured";

                FileOutputStream fos = null;
                try {
                    if (!mFolder.exists()) {
                        mFolder.mkdir();
                    }
                    if (!mCapture.exists()) {
                        mCapture.mkdir();
                    }
                    if (!imgFile.exists()) {
                        imgFile.createNewFile();
                    }
                    fos = new FileOutputStream(imgFile);
                    b.compress(Bitmap.CompressFormat.PNG, 100, fos);
                    fos.flush();
                    fos.close();
                    MediaStore.Images.Media.insertImage(getActivity().getContentResolver(), b, "Screen", "screen");
                }catch (FileNotFoundException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }



                final Intent shareIntent = new Intent(Intent.ACTION_SEND);
                shareIntent.setType("image/jpg");
                final File photoFile = new File(extr,fileName);
                shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(photoFile));
                startActivity(Intent.createChooser(shareIntent, "Share image using"));

here mContentView is the parent view of your surface view. apply this and let me know if you are not getting image screen shots.