Thread: combobox reacts strangely to a mouse

I have made a combobox in a simple dialog like this

Code:

CONTROL "", IDCOMBO, "ComboBox", WS_BORDER|CBS_DROPDOWNLIST|CBS_HASSTRINGS|WS_VSCROLL|CBS_SORT , 28, 28, 84,300

I have added a couple of options to it, and i can select them with the keyboard.
However, when i click with a mouse on the combobox i get an empty dropdownbox which does not react to mouseclicks. I have to use the keyboard to make the options visible and to select one.

this is the command handling procedure (or whatever it is called):

Code:

BOOL CALLBACK MainDlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	HWND hParent = GetParent(hwnd);	
	HWND hBut;
	RECT rectParent;
	RECT rectBut;
	HWND hStatus = GetDlgItem(hwnd, ID_TEX_STATUS); 
	int i;
	GetClientRect(hParent,&rectParent);
    switch(msg)
    {
		case WM_INITDIALOG:
			 
			SendMessage(GetDlgItem(hwnd,IDCOMBO),  CB_RESETCONTENT ,0,0);
			EnableWindow(GetDlgItem(hwnd, IDCOMBO), false);
			EnableWindow(GetDlgItem(hwnd, IDCOMBO), true); 
			SendMessage(GetDlgItem(hwnd,IDCOMBO),  CB_ADDSTRING ,0,(LPARAM)"option1");
			SendMessage(GetDlgItem(hwnd,IDCOMBO),  CB_ADDSTRING ,0,(LPARAM)"option2");
			SendMessage(GetDlgItem(hwnd,IDCOMBO),  CB_ADDSTRING ,0,(LPARAM)"option3");
			SendMessage(GetDlgItem(hwnd, IDCOMBO),CB_SELECTSTRING,(WPARAM)-1,(LPARAM)"option3");
            return true;
		break;
		case WM_MOVE:
            return true;
		break;
        case WM_CLOSE:
            PostQuitMessage(WM_QUIT);
            return true;
        break;
        case WM_COMMAND:
            switch(LOWORD(wParam))
            {
				case ID_BUT_GO:

					SendMessage(GetDlgItem(hwnd, IDCOMBO),CB_SELECTSTRING,(WPARAM)-1,(LPARAM)"option1"); 
					SendMessage(hStatus,WM_SETTEXT,(WPARAM)NULL,(LPARAM) "blablabla");		 
					return true;
				break;
				case ID_BUT_EXIT:
					
					PostQuitMessage(WM_QUIT);
					return true;
				break;	
				case IDCOMBO:
					//MessageBox(hwnd, "combo is used", "WARNING",MB_OK | MB_ICONEXCLAMATION);
					return true;
				break;
                default:
                return false;
            }
        break;
        default:
        return false;
    }
    return false;
}

I found a solution to my problem but i havent got a clue why this works.

Instead of using CreateDialog i used DialogBox and now it works.
If somebody knows why a combobox does NOT work with CreateDialog but does work with DialogBox i would really like to hear it.

@ken, i dont exactly understand what u mean, but do u think that could cause the difference in usage of CreateDialog / DialogBox?
I mean there is no way i can get a working combobox on a dialog which is created with CreateDialog.