Hello World from Programming Microsoft Windows CE .NET won't compile

[ddeham]

I can't get the HelloCE.cpp program listed on pages 30-33 in Douglas Boling's Programming Microsoft Windows CE .NET to compile! I am running Microsoft Embedded Visual C++ 4.0 SP2. I copied the code from the CD included with the book to my hard drive. I opened the workspace file. Here's what the compiler says when I try to compile it for POCKET PC 2003, Win32 (WCE ARMV4) Release, POCKET PC 2003 Device:

--------------------Configuration: HelloCE - Win32 (WCE ARMV4) Release--------------------
Compiling...
HelloCE.cpp
C:\Documents and Settings\Dan\My Documents\Code\Chap01\HelloCE\HelloCE.cpp(55) : error C2086: 'hWnd' : redefinition
C:\Documents and Settings\Dan\My Documents\Code\Chap01\HelloCE\HelloCE.cpp(58) : error C2440: 'return' : cannot convert from 'const int' to 'struct HWND__ *'
Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast
Error executing clarm.exe.

HelloCE.exe - 2 error(s), 0 warning(s)
-------------------------------------------------------------------------------------------------------
The problem is with these few lines of code:
#if defined(WIN32_PLATFORM_PSPC)
// If Pocket PC, only allow one instance of the application
HWND hWnd = FindWindow (szAppName, NULL);
if (hWnd) {
SetForegroundWindow ((HWND)(((DWORD)hWnd) | 0x01));
return -1;
}
#endif

I went to go to the support page listed in the book.

http://www.microsoft.com/mspress/support/

I clicked on the Support link for "Microsoft Press Books and Microsoft Press Book CDs." I clicked on "Search for corrections using the ISBN." I typed in the ISBN for the book (0-7356-1884-4), and it said: "We Currently Have No Documents That Match Your Search"! Please help! Please reply!

Thanks,

Dan



// HelloCE.h
//======================================================================
// Header file
//
// Written for the book Programming Windows CE
// Copyright (C) 2003 Douglas Boling
//================================================================
// Returns number of elements
#define dim(x) (sizeof(x) / sizeof(x[0]))

//----------------------------------------------------------------------
// Generic defines and data types
//
struct decodeUINT { // Structure associates
UINT Code; // messages
// with a function.
LRESULT (*Fxn)(HWND, UINT, WPARAM, LPARAM);
};
struct decodeCMD { // Structure associates
UINT Code; // menu IDs with a
LRESULT (*Fxn)(HWND, WORD, HWND, WORD); // function
};

//----------------------------------------------------------------------
// Function prototypes
//
HWND InitInstance (HINSTANCE, LPWSTR, int);
int TermInstance (HINSTANCE, int);

// Window procedures
LRESULT CALLBACK MainWndProc (HWND, UINT, WPARAM, LPARAM);

// Message handlers
LRESULT DoPaintMain (HWND, UINT, WPARAM, LPARAM);
LRESULT DoDestroyMain (HWND, UINT, WPARAM, LPARAM);

//------------------------------------------------------------------------------------------------------------------------------------
//------------------------------------------------------------------------------------------------------------------------------------

// HelloCE.cpp
//======================================================================
// HelloCE - A simple application for Windows CE
//
// Written for the book Programming Windows CE
// Copyright (C) 2003 Douglas Boling
//======================================================================
#include <windows.h> // For all that Windows stuff
#include "helloce.h" // Program-specific stuff

//----------------------------------------------------------------------
// Global data
//
const TCHAR szAppName[] = TEXT("HelloCE");
HINSTANCE hInst; // Program instance handle

// Message dispatch table for MainWindowProc
const struct decodeUINT MainMessages[] = {
WM_PAINT, DoPaintMain,
WM_DESTROY, DoDestroyMain,
};

//======================================================================
// Program entry point
//
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPWSTR lpCmdLine, int nCmdShow) {
MSG msg;
int rc = 0;
HWND hwndMain;

// Initialize this instance.
hwndMain = InitInstance (hInstance, lpCmdLine, nCmdShow);
if (hwndMain == 0) return 0x10;

// Application message loop
while (GetMessage (&msg, NULL, 0, 0)) {
TranslateMessage (&msg);
DispatchMessage (&msg);
}
// Instance cleanup
return TermInstance (hInstance, msg.wParam);
}
//----------------------------------------------------------------------
// InitInstance - Instance initialization
//
HWND InitInstance (HINSTANCE hInstance, LPWSTR lpCmdLine, int nCmdShow) {
WNDCLASS wc;
HWND hWnd;

// Save program instance handle in global variable.
hInst = hInstance;

#if defined(WIN32_PLATFORM_PSPC)
// If Pocket PC, only allow one instance of the application
HWND hWnd = FindWindow (szAppName, NULL);
if (hWnd) {
SetForegroundWindow ((HWND)(((DWORD)hWnd) | 0x01));
return -1;
}
#endif

// Register application main window class.
wc.style = 0; // Window style
wc.lpfnWndProc = MainWndProc; // Callback function
wc.cbClsExtra = 0; // Extra class data
wc.cbWndExtra = 0; // Extra window data
wc.hInstance = hInstance; // Owner handle
wc.hIcon = NULL, // Application icon
wc.hCursor = LoadCursor (NULL, IDC_ARROW);// Default cursor
wc.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH);
wc.lpszMenuName = NULL; // Menu name
wc.lpszClassName = szAppName; // Window class name

if (RegisterClass (&wc) == 0) return 0;

// Create main window.
hWnd = CreateWindow (szAppName, // Window class
TEXT("HelloCE"), // Window title
// Style flags
WS_VISIBLE | WS_CAPTION | WS_SYSMENU,
CW_USEDEFAULT, // x position
CW_USEDEFAULT, // y position
CW_USEDEFAULT, // Initial width
CW_USEDEFAULT, // Initial height
NULL, // Parent
NULL, // Menu, must be null
hInstance, // Application instance
NULL); // Pointer to create
// parameters
if (!IsWindow (hWnd)) return 0; // Fail code if not created.

// Standard show and update calls
ShowWindow (hWnd, nCmdShow);
UpdateWindow (hWnd);
return hWnd;
}
//----------------------------------------------------------------------
// TermInstance - Program cleanup
//
int TermInstance (HINSTANCE hInstance, int nDefRC) {
return nDefRC;
}
//======================================================================
// Message handling procedures for main window
//
//----------------------------------------------------------------------
// MainWndProc - Callback function for application window
//
LRESULT CALLBACK MainWndProc (HWND hWnd, UINT wMsg, WPARAM wParam,
LPARAM lParam) {
INT i;
//
// Search message list to see if we need to handle this
// message. If in list, call procedure.
//
for (i = 0; i < dim(MainMessages); i++) {
if (wMsg == MainMessages.Code)
return (*MainMessages.Fxn)(hWnd, wMsg, wParam, lParam);
}
return DefWindowProc (hWnd, wMsg, wParam, lParam);
}
//----------------------------------------------------------------------
// DoPaintMain - Process WM_PAINT message for window.
//
LRESULT DoPaintMain (HWND hWnd, UINT wMsg, WPARAM wParam,
LPARAM lParam) {
PAINTSTRUCT ps;
RECT rect;
HDC hdc;

// Get the size of the client rectangle
GetClientRect (hWnd, &rect);

hdc = BeginPaint (hWnd, &ps);
DrawText (hdc, TEXT ("Hello Windows CE!"), -1, &rect,
DT_CENTER | DT_VCENTER | DT_SINGLELINE);

EndPaint (hWnd, &ps);
return 0;
}
//----------------------------------------------------------------------
// DoDestroyMain - Process WM_DESTROY message for window.
//
LRESULT DoDestroyMain (HWND hWnd, UINT wMsg, WPARAM wParam,
LPARAM lParam) {
PostQuitMessage (0);
return 0;
}

 

[xwb]

Obviously whoever wrote the book has never tried compiling the code on the proper compiler. It is moaning about

hWnd being declared twice
returning -1 which is an integer. What it is expecting is an HWND.


Try changing the code to this

#if defined(WIN32_PLATFORM_PSPC)
    // If Pocket PC, only allow one instance of the application
    HWND hPPCWnd = FindWindow (szAppName, NULL);
    if (hPPCWnd) {
        SetForegroundWindow ((HWND)(((DWORD)hPPCWnd) | 0x01));    
        return (HWND)(-1);
    }
#endif

 

[ddeham]

That worked! Thanks a lot!

Dan