Loading a combobox win32

Hi,

I am trying to create a combo box on a dialog using win32 api in vc++ 6.0. I added the combo box control using the dialog resource editor with type as Dropdown and owner draw set to 'No'. Then I add data to it programatically. I have the following classes

Code:

class CmbBox: public SimpleControl {
public:
	CmbBox (HWND hwndParent, int id, BOOL initialState=TRUE)
		 : SimpleControl (hwndParent, id, initialState)
	{}
   void AddItem (char* buf) {
            SendMessage(_hWnd, CB_ADDSTRING, (WPARAM)0, (LPARAM)buf);
      
   }
   void SetString (char buf[20])
	{
       SendMessage (_hWnd, WM_SETTEXT, 0, (LPARAM) buf);
	}
};

Then i create the object for CmbBox in another class Controller

CmbBox _cmbSetting;

and the constructor initializes it

Controller::Controller (HWND hwnd)
: _cmbSetting (hwnd, IDC_CMBSETTING)

Then i call

_cmbSetting.AddItem("Data1");
_cmbSetting.AddItem("Data2");

But when i execute the application there is no data in the combobox. I am able to create all other controls like list box and buttons, but combo box comes up without any data.

Any pointers??
Thanks