Advanced MFC Programming

Chapter 13. Adding Special Features to Application
);
MAPPING_PROJECT
}
if(hMapFile != NULL)
{
lpMapAddress=(LPSTR)MapViewOfFile
(
hMapFile,
FILE_MAP_ALL_ACCESS,
0,
0,
0
);
if(lpMapAddress != NULL)
{
szText=lpMapAddress;
}
CEdit &editCtrl=((CEditView *)GetActiveView())->GetEditCtrl();
editCtrl.SetSel(0, -1);
editCtrl.ReplaceSel(szText);
}
return (LONG)TRUE;
There are other methods for sharing memory among different processes, such as DDE and OLE.
Comparing to the two methods, file mapping method is relatively simple and easy to implement.
Summary
1) Before a window is created, we must stuff a WNDCLASS type object, register the window class name, and
use this name to create the window. Class WNDCLASS contains useful information about the window
such as mainframe menu, default icon, default cursor shape, brush that will be used to erase the
background, and the window class name.
1) To implement one-instance application, we need to register our own window class name, and override
function CWnd::PreCreateWindow(…). Before the window is created, we need to replace the default
window class name with the new one. By doing this, we can implement one-instance application by
searching for registered window class name: before registering the window class, we can check if there
already exists a window that has the same class name. If so, the application simply exits.
1) We can call function CWnd::FindWindow(…) to find out a window with a specific class name or
window name in the system.
1) The document/view structure is implemented by class CSingleDocTemplate or CMutiDocTemplate. If
we want to create an application that does not use document/view structure, we need to eliminate the
procedure of creating CSingleDocTemplate or CMutiDocTemplate type object and call function
CWnd::Create(…) to create the mainframe window by ourselves.
1) We can create several CMultiDocTemplate type objects in an application to let it support multiple
views or multiple documents.
1) Caption bar and window frame belong to non-client area. To paint non-client area, we need to handle
messages WM_NCPAINT and WM_NCACTIVATE.
1) To create a window with transparent background, we need to specify style WS_EX_TRANSPARENT while
creating the window.
1) An application can save its states in the system registry by calling function
CWinApp::SetRegistryKey(…). The information can be saved and loaded by calling the following
functions: CWinApp::WriteProfileInt(…), CWinApp::WriteProfileString(…), CWinApp::
GetProfileInt(…)., CWinApp::GetProfileString(…).
1) To exchange user defined messages between two different processes, we must use function
::RegisterWindowMessage(…) to register the messages.
1) Calling function CWnd::SetWindowPos(…) using parameter CWnd::wndTopMost will make a window
always stay on top of any other window.
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