int DialogBoxIndirect(hInstance,hDialogTemplate, hWndParent,lpDialogFunc)
This function creates an application's modal dialog box that has the size, style, and controls specified by the dialog-box template associated with the hDialogTemplate parameter. The hWndParent parameter identifies the application window that owns the dialog box. The callback function pointed to by lpDialogFunc processes any messages received by the dialog box.
The DialogBoxIndirect function does not return control until the callback function terminates the modal dialog box by calling the EndDialog function.
| Parameter | Type/Description | |
| hInstance | HANDLE Identifies an instance of the module whose executable file contains the dialog-box template. | |
| hDialogTemplate | HANDLE Identifies a block of global memory that contains a DLGTEMPLATE data structure. | |
| hWndParent | HWND Identifies the window that owns the dialog box. | |
| lpDialogFunc | FARPROC Is the procedure-instance address of the dialog function. See the following “Comments” section for details. |
The return value specifies the value of the wResult parameter specified in the EndDialog function that is used to terminate the dialog box. Values returned by the application's dialog box are processed by Windows and are not returned to the application. The return value is –1 if the function could not create the dialog box.
A dialog box can contain up to 255 controls.
The callback function must use the Pascal calling convention and be declared FAR.
BOOL FAR PASCAL DialogFunc(hDlg, wMsg, wParam, lParam)
HWND hDlg;
WORD wMsg;
WORD wParam;
DWORD lParam;
DialogFunc is a placeholder for the application-supplied function name. The actual name must be exported by including it in an EXPORTS statement in the application's module-definition file.
| Parameter | Description | |
| hDlg | Identifies the dialog box that receives the message. | |
| wMsg | Specifies the message number. | |
| wParam | Specifies 16 bits of additional message-dependent information. | |
| lParam | Specifies 32 bits of additional message-dependent information. |
Return Value
The callback function should return nonzero if the function processes the message and zero if it does not.
Comments
Although the callback function is similar to a window function, it must not call the DefWindowProc function to process unwanted messages. Unwanted messages are processed internally by the dialog-class window function.
The callback-function address, passed as the lpDialogFunc parameter, must be created by using the MakeProcInstance function.