How to Handle the Back Key for Dialog Boxes Without Edit Controls
4/19/2010
When a user presses the Back key in a dialog box that does not have any edit controls, the Back key sends a Windows Embedded CE WM_COMMAND message with the command ID IDCANCEL to the dialog box. The following code example illustrates how to handle the WM_COMMAND message.
BOOL rb;
int rc;
{
switch(LOWORD(wParam))
{
// User closes the dialog box by pressing the Back key.
{
rb = EndDialog(hwnd, 0);
if (rb == FALSE) // EndDialog failed.
{
rc = MessageBox(NULL, _T("Could not destroy dialog box."),
_T("Error"), MB_OK);
if (rc == 0) // Not enough memory to create MessageBox.
return E_OUTOFMEMORY;
return E_FAIL; // Replace with specific error handling.
}
else // EndDialog succeeded.
return S_OK;
} // case IDCANCEL
} // switch
break; // from case WM_COMMAND
}