Windows CE Programming - writing text to the display: 365 programming project day forty one

/* 2010-01 john pfeiffer writing text to the display */

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <windowsx.h>
#include <commctrl.h>
#include <aygshell.h>
#define IDC_ExitButton 40099

/* wchar[] must be cleared empty first! */ 
void stringToWchar( char string[128], wchar_t longstring[128] ) {
    int i=0;
    for( i=0; i < strlen( string ); i++) {
        longstring[i] = (WCHAR)string[i]; 
    } 
}

/* convert a char string to wchar and Display it on the screen */

/* here we take the handle to device context (aka logical buffer about the 
screen and begin painting it - we then draw a single line of text (windows 
wide character format but first converting the character string to wchar string)...
The end paint matches the begin paint and without them the text will flicker constantly */

VOID APIENTRY drawText( HWND hwnd, char text[128], int x, int y ) {
    HDC hdc;
    PAINTSTRUCT ps;
    wchar_t outputtext [128];
    hdc = BeginPaint(hwnd, &ps);
    hdc = GetDC(hwnd);
    /* good practice to zero things before using them */
    memset( outputtext , 0, sizeof( outputtext ));
    stringToWchar( text, outputtext );
    ExtTextOut( hdc, x, y, NULL, NULL, outputtext , _tcslen(outputtext ), NULL);
    ReleaseDC(hwnd, hdc);
    EndPaint(hwnd, &ps);
}

VOID APIENTRY initializeBackground( HWND hwnd ) {
    HDC hdc;
    PAINTSTRUCT ps;
    hdc = BeginPaint(hwnd, &ps);
    EndPaint(hwnd, &ps);
}

/* our big message loop with all sorts of interrupt options */

LRESULT CALLBACK MenuWndProc( HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
    switch (message) {
        case WM_LBUTTONDOWN:
            break;
        case WM_CHAR:
            break;
        case WM_KEYDOWN:
            break;
        case WM_COMMAND:
            switch(LOWORD( wParam )) {
                case IDC_ExitButton:
                    PostQuitMessage(0);
                    break;
                default:
                    break;
            }
            break;
        case WM_DESTROY:
            PostQuitMessage(0);
            break;
        case WM_PAINT:
            drawText( hwnd, "press quit button to quit", 40, 40 );
            break;
        case WM_CREATE:
            initializeBackground( hwnd );
            break;
        default:
            return DefWindowProc( hwnd, message, wParam, lParam );
            break;
        }
    return 0;
} /* end function MenuWndProc */

int APIENTRY WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int ncmdshow ) {
    HWND hwnd = NULL;
    HWND ExitButton= NULL;
    MSG msg;
    WNDCLASS wc;
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = (WNDPROC)MenuWndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = 0;
    wc.hCursor = 0;
    wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = (LPTSTR) L"App";
    if(! RegisterClass (&wc)) {
        MessageBox(NULL, TEXT("errors "), L"IMPORTANT", MB_OK);
        return 0;
    }

    /* Make sure the window uses the Menu App Class name defined above! */
    hwnd = CreateWindow (L"App", L"menu demo", WS_VISIBLE, CW_USEDEFAULT,
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, (HWND)NULL, NULL,
        hInstance, (LPSTR)NULL);

    /* -------- -------- -------- -------- */

    ExitButton = CreateWindow( L"BUTTON", L"quit", 
        WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
        0, 0, 30, 30, hwnd, (HMENU)IDC_ExitButton, hInstance, NULL); 
    ShowWindow(hwnd, ncmdshow);
    UpdateWindow(hwnd);

    while(GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    } 
    return msg.wParam;
} /* end WinMain */