static final int REQUEST_TAKE_PHOTO = 1;
private int SELECT_FILE = 2;
private static Button btnclick;
private String mCurrentPhotoPath;
private static RecyclerView recyclerView;
ArrayList<Data_Model> arrayList;
String chkpath = null;
MyAdapter m;
int i = 0;
private String userChoosenTask;
private Uri fileUri; // file url to store image/video

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    btnclick = (Button) findViewById(R.id.click);
    recyclerView = (RecyclerView) findViewById(R.id.recycler_view);

    arrayList = new ArrayList<>();
    m = new MyAdapter();
    Log.d("oncreate", "set adapter");
    recyclerView.setAdapter(m);
    ViewGroup.LayoutParams params = recyclerView.getLayoutParams();
    params.height = 200;
    recyclerView.setLayoutParams(params);
    LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
    recyclerView.setLayoutManager(linearLayoutManager);


    //Camera Click image
    btnclick.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            selectImage();

        }
    });


}

public void takepicture() {
    Log.d("Cameraclick", "takepicture");

    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);


    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        File photoFile = null;
        try {
            photoFile = createImageFile();
        } catch (IOException ex) {
            // Error occurred while creating the File
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                    Uri.fromFile(photoFile));
            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }
}

private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
            imageFileName,  /* prefix */
            ".jpg",         /* suffix */
            storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = image.getAbsolutePath();
    return image;


}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    if (resultCode == RESULT_OK) {
        if (requestCode == REQUEST_TAKE_PHOTO) {

            // Save Image To Gallery
            Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
            File f = new File(mCurrentPhotoPath);
            Uri contentUri = Uri.fromFile(f);
            mediaScanIntent.setData(contentUri);
            this.sendBroadcast(mediaScanIntent);
            String clickpath = mCurrentPhotoPath;
            Data_Model data_model = new Data_Model();
            data_model.setImage(clickpath);
            arrayList.add(data_model);
            m.notifyDataSetChanged();


        } else if (requestCode == SELECT_FILE) {
            Log.d("gallery", "checkpointd");
            onSelectFromGalleryResult(data);
        }
    }

}


class MyAdapter extends RecyclerView.Adapter<MyAdapter.Myviewholder> {

    @Override
    public Myviewholder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = getLayoutInflater().inflate(R.layout.item_rowchk, parent, false);
        Myviewholder myviewholder = new Myviewholder(v);
        Log.d("myactivty ", "oncreateViewHolder");

        return myviewholder;
    }

    @Override
    public void onBindViewHolder(Myviewholder holder, final int position) {
        final Data_Model m = arrayList.get(position);
        Log.d(" myactivty", "onBindviewholder" + position);
        //holder.imageView.setVisibility(View.VISIBLE);
        // bimatp factory
        BitmapFactory.Options options = new BitmapFactory.Options();
        // downsizing image as it throws OutOfMemory Exception for larger
        // images
        options.inSampleSize = 20;
        final Bitmap bitmap = BitmapFactory.decodeFile(m.getImage(), options);
        holder.imageView.setImageBitmap(bitmap);
        holder.imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(getApplicationContext(), ImageDisplay.class);
                String chkpath = m.getImage();
                intent.putExtra("path", chkpath);
                Log.d("intent", "new activity");
                startActivity(intent);
            }
        });
        holder.imageView.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View view) {

                final int pst = position;
                DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        switch (which) {
                            case DialogInterface.BUTTON_POSITIVE:
                                arrayList.remove(position);
                                notifyItemRemoved(position);
                                notifyItemRangeChanged(position, arrayList.size());
                                // Yes button clicked
                                Toast.makeText(MainActivity.this, "Yes Clicked",
                                        Toast.LENGTH_LONG).show();
                                break;

                            case DialogInterface.BUTTON_NEGATIVE:
                                // No button clicked
                                // do nothing
                                Toast.makeText(MainActivity.this, "No Clicked",
                                        Toast.LENGTH_LONG).show();
                                break;
                        }
                    }
                };

                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                builder.setMessage("Are you sure want to Delete ?")
                        .setPositiveButton("Yes", dialogClickListener)
                        .setNegativeButton("No", dialogClickListener).show();

                return true;
            }
        });


    }

    @Override
    public int getItemCount() {
        return arrayList.size();
    }

    public class Myviewholder extends RecyclerView.ViewHolder {
        public ImageView imageView;

        public Myviewholder(View itemView) {
            super(itemView);
            imageView = (ImageView) itemView.findViewById(R.id.image);
        }
    }
}

private void onSelectFromGalleryResult(Intent data) {

    Uri selectedImageUri = data.getData();
    String[] projection = {MediaStore.Images.Media.DATA};
    Cursor cursor = managedQuery(selectedImageUri, projection, null, null, null);
    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
    cursor.moveToFirst();
    String path = cursor.getString(column_index);
    Data_Model data_model = new Data_Model();
    data_model.setImage(path);
    arrayList.add(data_model);
    m.notifyDataSetChanged();
    // Toast.makeText(this, "" + path, Toast.LENGTH_LONG).show();
}

private void selectImage() {

    final CharSequence[] items = {"Take Photo", "Choose from Library",
            "Cancel"};

    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setTitle("Add Photo!");
    builder.setItems(items, new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int item) {
            boolean result = true;

            if (items[item].equals("Take Photo")) {
                userChoosenTask = "Take Photo";
                if (result)
                    takepicture();

            } else if (items[item].equals("Choose from Library")) {
                userChoosenTask = "Choose from Library";
                if (result)
                    galleryIntent();


            } else if (items[item].equals("Cancel")) {
                dialog.dismiss();
            }
        }
    });
    builder.show();
}


public void galleryIntent() {
    Intent intent = new Intent();
    intent.setType("image/*");
    intent.setAction(Intent.ACTION_GET_CONTENT);
    Log.d("gallery", "checkpointA");
    startActivityForResult(Intent.createChooser(intent, "Select File"), SELECT_FILE);
    Log.d("gallery", "checkpointB");
}