One of the IPF customizations you can do with your communication object is manipulating the IPF coverpage window.

When an online book is opened or when an application requests that IPF create a help instance, IPF creates a coverpage frame window. The coverpage window is the window in which all other information is displayed. IPF-controlled windows are children of the coverpage window, as are application-controlled windows.

IPF communication objects can change the look and functionality of the coverpage window. For example, a communication object can change the size or location of the coverpage, or remove its menu bar.

For HLP files, applications can change only the size of a help window. The application would do this by sending HM_SET_COVERPAGE_SIZE to the help instance created with WinCreateHelpInstance. Note that applications must not move the help window.

For INF files, the communication object must handle the OPEN_COVERPAGE event of the HM_NOTIFY message, then use WinSetWindowPos to set the size and position of the coverpage. The coverpage window's handle is in mp2.

When using WinSetWindowPos to change the position and size of the coverpage window, you must OR SWP_SHOW with SWP_MOVE or SWP_SIZE, or both.

You must return directly from your code when you handle this event. Do not pass the HM_NOTIFY message on to the default window procedure.

In addition to the techniques specified here for resizing and positioning the coverpage, once you have the handle to the coverpage you can use any of the other PM window manipulation techniques, such as manipulating the frame controls or menus. For example, to remove the coverpage's menu bar, you would call WinDestroyWindow in response to an OPEN_COVERPAGE event, as in the following example:

WinDestroyWindow(WinWindowFromID((HWND) mp2, FID_MENU));

Use other FID_* IDs to work with other parts of the coverpage window.

The code fragment in the following figure illustrates these techniques by changing the size and location of the coverpage and removing the menu bar.

HWND hwndCoverPage;
   .
   .
   .
   /* Inside the main switch statement in your window procedure... */
   case HM_NOTIFY:

      switch (SHORT1FROMMP(mp1)) {

         case OPEN_COVERPAGE:
            hwndCoverPage = (HWND) mp2;   /* Handle to coverpage is in mp2 */

            /* Remove the menu */
            WinDestroyWindow(WinWindowFromID(hwndCoverPage, FID_MENU));

            /* Change the size and location of coverpage */
            WinSetWindowPos(hwndCoverPage, 0, 10, 10, 200, 200,
                            SWP_SIZE | SWP_MOVE | SWP_SHOW);

            return TRUE;

      } /* endswitch */

      break;