Button

  case R.id.action_delete_items:
  
                CustomFragmentDialog mCustomFragmentDialog = new CustomFragmentDialog();
                mCustomFragmentDialog.caller = new CustomFragmentDialog.NoticeDialogListener() {
                    @Override
                    public void onDialogPositiveClick(DialogInterface dialog) {
                        clearData();
                        mTaskAdapter.notifyDataSetChanged();
                    }
                };
                mCustomFragmentDialog.show(getFragmentManager(), "");

                return true;