I'm using a resource file for my dialog boxes, menus, etc. in a C program in Visual Studio. Just wondering if a resource file has a global scope? Also, as a consequence of this, where is the ideal place in the program to call GetDlgItem to get the handle of a combobox and to load its list (as well as other similar tasks)?

Can someone give a simple example of adding a list item to a combo box in the context in which a resource file is being used rather than a when a combo box created explicitly in the code is being used?

CodePudding user response：

The information given in the comments answered the question sufficiently. What initially prompted the question was my desire and attempts to put items in a combo box list. The code below successfully accomplished this. This is mostly a Visual C autogenerated message handling procedure for a drop down menu entry called "Add" under a main menu "Edit." In the dialog generated by selecting Add there is a combo box which is designated here as IDC_COMBO1. (IDC_COMBO1 is the name given to the combobox in the resource file and is defined in resource.h so it is recognized here.) I added three lines to the code to put the entry "1st" into the combo box list. Also, as suggested by Richard Critten, I handled this in the WM_INITDIALOG message case which makes sense beside being simple and concise. The three lines were:

HWND hWndCB1;
hWndCB1 = GetDlgItem(hDlg, IDC_COMBO1);
SendMessage(hWndCB1, CB_ADDSTRING, 0, (LPARAM)TEXT("1st"));

The entry "1st" appeared in the list when I built the project. Thanks to those who commented, and I hope that this helps someone else who is attempting to accomplish this. The code of the message handling procedure is below.

INT_PTR CALLBACK Add(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{

    HWND hWndCB1;

    UNREFERENCED_PARAMETER(lParam);
    switch (message)
    {
    case WM_INITDIALOG:
        {   
            hWndCB1 = GetDlgItem(hDlg, IDC_COMBO1);
            SendMessage(hWndCB1, CB_ADDSTRING, 0, (LPARAM)TEXT("1st"));
            return (INT_PTR)TRUE; 
        }
        break;

    case WM_COMMAND:
        if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
        {
            EndDialog(hDlg, LOWORD(wParam));
            return (INT_PTR)TRUE;
        }
        break;
    }
    return (INT_PTR)FALSE;
}