Subj : Re: Need a little help
To   : borland.public.cpp.borlandcpp
From : Jeff Baker
Date : Sat May 29 2004 03:33 pm

Thanks Ed, your suggestion worked. I keep overlooking the basics. I placed
the InvalidateRect() and UpdateWindow() in the ProcessMenuSelection()
function and everything works fine (with a few other changes). When I placed
them in the DisplayCentigrade() and DisplayFahrenheit() functions the screen
kept refreshing itself (looked pretty cool actually). Here is how it looks
now;

[START OF CODE]
void DisplayCentigrade(HWND hwnd,HDC hdc,HDC hdcMem)
 {
 HBITMAP hbmOld = (HBITMAP)SelectObject(hdcMem,ga_centigrage);
 GetObject(ga_centigrage,sizeof(bitmap),&bitmap);
 BitBlt(hdc,787,679,bitmap.bmWidth,bitmap.bmHeight,hdcMem,0,0,SRCCOPY);
 SelectObject(hdcMem,hbmOld);
 }

void DisplayFahrenheit(HWND hwnd,HDC hdc,HDC hdcMem)
 {
 HBITMAP hbmOld = (HBITMAP)SelectObject(hdcMem,ga_fahrenheit);
 GetObject(ga_fahrenheit,sizeof(bitmap),&bitmap);
 BitBlt(hdc,787,679,bitmap.bmWidth,bitmap.bmHeight,hdcMem,0,0,SRCCOPY);
 SelectObject(hdcMem,hbmOld);
 }

void ProcessMenuSelection(HWND hwnd,WPARAM wParam)
 {
 HMENU menu;
 int accept_change;
 switch(LOWORD(wParam))
  {
  case ID_TEMP_C:
   accept_change = MessageBox(hwnd,"Oil temperature will be displayed using
the Centigrade scale","Configuration Change Notice",MB_OKCANCEL |
MB_ICONINFORMATION);
   if (accept_change == IDOK)
    {
    temp_select = CENTIGRADE;
    menu = GetMenu(hwnd);
    CheckMenuItem(menu,ID_TEMP_C,MF_CHECKED);
    CheckMenuItem(menu,ID_TEMP_F,MF_UNCHECKED);
    HDC hdc = BeginPaint(hwnd,&paint_struct);
    HDC hdcMem = CreateCompatibleDC(hdc);
    if (hdcMem ==  NULL)
     {
     LPVOID message_buffer;
     MessageBeep(MB_ICONEXCLAMATION);

FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM|FORM
AT_MESSAGE_IGNORE_INSERTS,NULL,GetLastError(),MAKELANGID(LANG_NEUTRAL,SUBLAN
G_DEFAULT),(LPTSTR) &message_buffer,0,NULL);

MessageBox(NULL,(LPCTSTR)message_buffer,app_name,MB_ICONEXCLAMATION|MB_OK|MB
_SYSTEMMODAL);
     LocalFree(message_buffer);
     }
    DisplayCentigrade(hwnd,hdc,hdcMem);
    InvalidateRect(hwnd,NULL,TRUE);
    UpdateWindow(hwnd);
    DeleteDC(hdcMem);
    EndPaint(hwnd,&paint_struct);
    }
   break;
  case ID_TEMP_F:
   accept_change = MessageBox(hwnd,"Oil temperature will be displayed using
the Fahrenheit scale","Configuration Change Notice",MB_OKCANCEL |
MB_ICONINFORMATION);
   if (accept_change == IDOK)
    {
    temp_select = FAHRENHEIT;
    menu = GetMenu(hwnd);
    CheckMenuItem(menu,ID_TEMP_F,MF_CHECKED);
    CheckMenuItem(menu,ID_TEMP_C,MF_UNCHECKED);
    HDC hdc = BeginPaint(hwnd,&paint_struct);
    HDC hdcMem = CreateCompatibleDC(hdc);
    if (hdcMem ==  NULL)
     {
     LPVOID message_buffer;
     MessageBeep(MB_ICONEXCLAMATION);

FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM|FORM
AT_MESSAGE_IGNORE_INSERTS,NULL,GetLastError(),MAKELANGID(LANG_NEUTRAL,SUBLAN
G_DEFAULT),(LPTSTR) &message_buffer,0,NULL);

MessageBox(NULL,(LPCTSTR)message_buffer,app_name,MB_ICONEXCLAMATION|MB_OK|MB
_SYSTEMMODAL);
     LocalFree(message_buffer);
     }
    DisplayFahrenheit(hwnd,hdc,hdcMem);
    InvalidateRect(hwnd,NULL,TRUE);
    UpdateWindow(hwnd);
    DeleteDC(hdcMem);
    EndPaint(hwnd,&paint_struct);
    }
   break;

  break;
  }
 }

LRESULT CALLBACK WndProc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM lParam)
 {
 switch(msg)
  {
  case WM_CREATE:
   {
   ga_bmp = LoadBitmap(GetModuleHandle(NULL),MAKEINTRESOURCE(IDB_GA));
   ga_centigrage =
LoadBitmap(GetModuleHandle(NULL),MAKEINTRESOURCE(IDB_CENTIGRADE));
   ga_fahrenheit =
LoadBitmap(GetModuleHandle(NULL),MAKEINTRESOURCE(IDB_FAHRENHEIT));
   break;
   }
  case WM_PAINT:
   {
   HDC hdc = BeginPaint(hwnd,&paint_struct);
   HDC hdcMem = CreateCompatibleDC(hdc);
   if (hdcMem ==  NULL)
    {
    LPVOID message_buffer;
    MessageBeep(MB_ICONEXCLAMATION);

FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM|FORM
AT_MESSAGE_IGNORE_INSERTS,NULL,GetLastError(),MAKELANGID(LANG_NEUTRAL,SUBLAN
G_DEFAULT),(LPTSTR) &message_buffer,0,NULL);

MessageBox(NULL,(LPCTSTR)message_buffer,app_name,MB_ICONEXCLAMATION|MB_OK|MB
_SYSTEMMODAL);
    LocalFree(message_buffer);
    }
   HBITMAP hbmOld = (HBITMAP)SelectObject(hdcMem,ga_bmp);
   GetObject(ga_bmp,sizeof(bitmap),&bitmap);
   BitBlt(hdc,0,0,bitmap.bmWidth,bitmap.bmHeight,hdcMem,0,0,SRCCOPY);
   SelectObject(hdcMem,hbmOld);
   if (CGA.temp_select == CENTIGRADE) DisplayCentigrade(hwnd,hdc,hdcMem);
   else DisplayFahrenheit(hwnd,hdc,hdcMem);
   DeleteDC(hdcMem);
   EndPaint(hwnd,&paint_struct);
   }
   break;

[END OF CODE]

Thanks again Ed for putting up with my rookie questions, your the BEST!

- Jeff Baker

"Ed Mulroy [TeamB]" <dont_email_me@bitbuc.ket> wrote in message
news:40b78eeb@newsgroups.borland.com...
> Once the user has changed the setting and your functions have altered
> the memory bitmap how is Windows to know that you wish that it repaint
> the window?
>
> Try adding these lines at the end of the DisplayCentigrade and
> DisplayFahrenheit functions.
>
>   InvalidateRect(hwnd, NULL, TRUE);
>   UpdateWindow(hwnd);
>
> .  Ed
>
> > Jeff Baker wrote in message
> > news:40b78cb1@newsgroups.borland.com...
>
>

.