ขอคำแนะนำ Android Studio ในการสร้างไฟล์ Excel (XLS) บนมือถือ ด้วยครับ

public class MainActivity extends Activity implements OnClickListener {

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

        Button button = (Button) findViewById(R.id.button);
        button.setOnClickListener(this);
    }

    @Override
    public void onClick(View arg0) {

        String Fnamexls="testfile"  + ".xls";

        File sdCard = Environment.getExternalStorageDirectory();

        File directory = new File (sdCard.getAbsolutePath() + "/newfolder");
        directory.mkdirs();

        File file = new File(directory, Fnamexls);

        WorkbookSettings wbSettings = new WorkbookSettings();
        wbSettings.setLocale(new Locale("en", "EN"));

        WritableWorkbook workbook;
        try {
            int a = 1;
            workbook = Workbook.createWorkbook(file, wbSettings);
            WritableSheet sheet = workbook.createSheet("First Sheet", 0);
            Label label = new Label(0, 2, "SECOND");
            Label label1 = new Label(0,1,"first");
            Label label0 = new Label(0,0,"HEADING");
            Label label3 = new Label(1,0,"Heading2");
            Label label4 = new Label(1,1,String.valueOf(a));

            try {
                sheet.addCell(label);
                sheet.addCell(label1);
                sheet.addCell(label0);
                sheet.addCell(label4);
                sheet.addCell(label3);
            } catch (RowsExceededException e) {
                e.printStackTrace();
            } catch (WriteException e) {
                e.printStackTrace();
            }
            workbook.write();

            try {
                workbook.close();
            } catch (WriteException e) {

                e.printStackTrace();
            }

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

}

/**
* Exports the cursor value to an excel sheet.
* Recommended to call this method in a separate thread,
* especially if you have more number of threads.
*  
* @param cursor
*/

private void exportToExcel(Cursor cursor) {		
	final String fileName = "TodoList.xls";
	
	//Saving file in external storage
	File sdCard = Environment.getExternalStorageDirectory();	
	File directory = new File(sdCard.getAbsolutePath() + "/javatechig.todo");
		
	//create directory if not exist
	if(!directory.isDirectory()){
		directory.mkdirs();	
	}
		
	//file path
	File file = new File(directory, fileName);
	
	WorkbookSettings wbSettings = new WorkbookSettings();
	wbSettings.setLocale(new Locale("en", "EN"));		
	WritableWorkbook workbook;
		
	try {
		workbook = Workbook.createWorkbook(file, wbSettings);			
		//Excel sheet name. 0 represents first sheet
		WritableSheet sheet = workbook.createSheet("MyShoppingList", 0);

		try {
			sheet.addCell(new Label(0, 0, "Subject")); // column and row
			sheet.addCell(new Label(1, 0, "Description"));				
			if (cursor.moveToFirst()) {
				do {
					String title = cursor.getString(cursor.getColumnIndex(DatabaseHelper.TODO_SUBJECT));
					String desc = cursor.getString(cursor.getColumnIndex(DatabaseHelper.TODO_DESC));

					int i = cursor.getPosition() + 1;						
					sheet.addCell(new Label(0, i, title));
					sheet.addCell(new Label(1, i, desc));						
				} while (cursor.moveToNext());
			}				
			//closing cursor
			cursor.close();					
		} catch (RowsExceededException e) {
			e.printStackTrace();
		} catch (WriteException e) {
			e.printStackTrace();
		}			
		workbook.write();		
		try {
			workbook.close();
		} catch (WriteException e) {
			e.printStackTrace();
		}
	} catch (IOException e) {
		e.printStackTrace();
	}
}