HOWTO: Center a Dialog Box on the Screen

ID: Q74798

The information in this article applies to:

Microsoft Windows Software Development Kit (SDK)
Microsoft Win32 Software Development Kit (SDK), on platform(s):
- Microsoft Windows NT, versions 3.5, 3.51

SUMMARY

When an application developed for the Microsoft Windows graphical environment displays a dialog box, centering the dialog box on the screen is sometimes desirable. However, on systems with high- resolution displays, the application displaying the dialog box may be nowhere near the center of the screen. In these cases, it is preferable to place the dialog near the application requesting input.

To center a dialog box on the screen before it is visible, add the following lines to the processing of the WM_INITDIALOG message:


    {
    RECT rc;

    GetWindowRect(hDlg, &rc);

    SetWindowPos(hDlg, NULL,
       ((GetSystemMetrics(SM_CXSCREEN) - (rc.right - rc.left)) / 2),
       ((GetSystemMetrics(SM_CYSCREEN) - (rc.bottom - rc.top)) / 2),
       0, 0, SWP_NOSIZE | SWP_NOACTIVATE);
    }

This code centers the dialog horizontally and vertically.

Under Windows 95 or later and NT 4.0 or later, the style DS_CENTER to get the same effect.


Keywords          : kbDlg kbNTOS350 kbNTOS351 kbGrpUser 
Version           : 
Platform          : 
Issue type        : kbhowto

Last Reviewed: March 7, 1999