Android Listview onListItemClick get Sqlite Id

public List<Emp> AllRecords() 
{
    List<Emp> dataset = new ArrayList<Emp>();
    Cursor cursor = database.query(DatabaseHelper.TABLE_EMPLOYEE,allColumns, null, null,null, null, null);

    cursor.moveToFirst();
    while (!cursor.isAfterLast()) {
        Emp obj = cursorToContact(cursor);
        dataset.add(obj);
      cursor.moveToNext();
    }
    cursor.close();
    return dataset;
}

private Emp cursorToContact(Cursor cursor) 
{
    Emp obj = new Emp();
    obj.setId(cursor.getInt(0));
    obj.setName(cursor.getString(1));
    obj.setDesig(cursor.getString(2));
    return obj;
}


//--------------
list_data = (ArrayList<Emp>) qh.AllRecords();
CustomListAdapter adapter = new CustomListAdapter(MainActivity.this,list_data);
//---------

public void onItemClick(AdapterView arg0, View arg1, int arg2,long arg3) 

{ 
  int id=list_data.get(arg2); //Type mismatch: cannot convert from Emp to int

  Toast.makeText(MainActivity.this,id,Toast.LENGTH_SHORT).show(); 

} 

Plz tell what should i write to get id.