MISC.C

// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF 
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO 
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A 
// PARTICULAR PURPOSE. 
// 
// Copyright 1993 - 1998 Microsoft Corporation.  All Rights Reserved. 
// 
//  MODULE:   misc.c 
// 
//  PURPOSE:  Contains all helper functions "global" to the application. 
// 
//  FUNCTIONS: 
//    CenterWindow - Center one window over another. 
// 
//  COMMENTS: 
// 
// 
 
#include <windows.h>            // required for all Windows applications 
#include <windowsx.h> 
 
#ifdef WIN16 
#include "win16ext.h"           // required only for win16 applications 
#endif 
#include "globals.h"            // prototypes specific to this application 
 
 
 
// 
//  FUNCTION: CenterWindow(HWND, HWND) 
// 
//  PURPOSE:  Center one window over another. 
// 
//  PARAMETERS: 
//    hwndChild - The handle of the window to be centered. 
//    hwndParent- The handle of the window to center on. 
// 
//  RETURN VALUE: 
// 
//    TRUE  - Success 
//    FALSE - Failure 
// 
//  COMMENTS: 
// 
//    Dialog boxes take on the screen position that they were designed 
//    at, which is not always appropriate. Centering the dialog over a 
//    particular window usually results in a better position. 
// 
 
BOOL CenterWindow(HWND hwndChild, HWND hwndParent) 
{ 
    RECT    rcChild, rcParent; 
    int     cxChild, cyChild, cxParent, cyParent; 
    int     cxScreen, cyScreen, xNew, yNew; 
    HDC     hdc; 
 
    // Get the Height and Width of the child window 
    GetWindowRect(hwndChild, &rcChild); 
    cxChild = rcChild.right - rcChild.left; 
    cyChild = rcChild.bottom - rcChild.top; 
 
    // Get the Height and Width of the parent window 
    GetWindowRect(hwndParent, &rcParent); 
    cxParent = rcParent.right - rcParent.left; 
    cyParent = rcParent.bottom - rcParent.top; 
 
    // Get the display limits 
    hdc = GetDC(hwndChild); 
    cxScreen = GetDeviceCaps(hdc, HORZRES); 
    cyScreen = GetDeviceCaps(hdc, VERTRES); 
    ReleaseDC(hwndChild, hdc); 
 
    // Calculate new X position, then adjust for screen 
    xNew = rcParent.left + ((cxParent - cxChild) / 2); 
    if (xNew < 0) 
    { 
        xNew = 0; 
    } 
    else if ((xNew + cxChild) > cxScreen) 
    { 
        xNew = cxScreen - cxChild; 
    } 
 
    // Calculate new Y position, then adjust for screen 
    yNew = rcParent.top  + ((cyParent - cyChild) / 2); 
    if (yNew < 0) 
    { 
        yNew = 0; 
    } 
    else if ((yNew + cyChild) > cyScreen) 
    { 
        yNew = cyScreen - cyChild; 
    } 
 
    // Set it, and return 
    return SetWindowPos(hwndChild, 
                        NULL, 
                        xNew, yNew, 
                        0, 0, 
                        SWP_NOSIZE | SWP_NOZORDER); 
}