1. Microsoft Foundation Classes

2. What is MFC? Set of C++ classes written by MS Simplifies writing complex programs Covers many areas: – GUI – I/O – O/S interfaces – ActiveX Framework for IE extensions Component of Windows

3. Why Use MFC? Faster development More code is reusable Many common tasks are "built-in" – Winmain, WndProc Smaller executable Uses all the C++ paradigms – Inheritance, polymorphism, etc.

4. MFC class categories CObject – the root class Application architecture classes Window, dialog, control Drawing, printing Datatypes Array, list, map File & DB Internet & networking OLE Debugging Used in this course

5. Cobject Think of it as the "master" class Serialization – Stream data to/from devices (disks) Runtime class info Debugging Some derived classes – Cmenu (menus & menu mgmt.) – CDC (device context & drawing) – CGdiObject (drawing devices – brushes, etc)

6. Related info MFC class hierarchy chart Macros & global variables WndProc (Win32API) buried in MFC library Message Maps – Names of events – Handler functions for those events – E.g.; ON_WM_MOVE for CMainFrame::OnMove – ON_WM_MOVE pre-defined constant – OnMove pre-defined fn in the CMainFrame class

7. WIn32API vs MFC Message handling Window gets moved WndProc() case WM_MOVE: movefn(); Win32API Window gets moved CMainFrame::OnMove MFC

8. Parts of a basic MFC Program - 1 MyWinApp.h #include class CMyWinApp : public CWinApp { public: virtual BOOL InitInstance(); };

9. Parts of a basic MFC Program – 2 MainFrame.h #include class CMainFrame : public CFrameWnd { private: // variables known to all CMainFrame members public: // define the prototypes for functions to handle window events CMainFrame();// class constructor // prototypes for members named in the MESSAGE MAP // The MESSAGE MAP is implemented in MainFrame.cpp //afx_msg int OnCreate(LPCREATESTRUCT lpCreateStruct); //afx_msg void OnShowWindow(BOOL bShow, UINT nStatus); afx_msg void OnMove(int x, int y); afx_msg void OnPaint(); // msg hndlr for WM_PAINT event void common(CWnd* wptr); DECLARE_MESSAGE_MAP(); }; // note: the "afx_msg" prefix is pre-VS 2005 and is #defined as empty

10. Parts of a basic MFC Program – 3 // Main.cpp #include "MyWinApp.h" CMyWinApp MyApplication;

11. Parts of a basic MFC Program – 4 // MyWinApp.cpp // create the window frame & display it #include "MyWinApp.h" #include "MainFrame.h" BOOL CMyWinApp::InitInstance() { CMainFrame *pFrame; pFrame = new CMainFrame; m_pMainWnd = pFrame; pFrame->ShowWindow(SW_SHOW); pFrame->UpdateWindow(); return TRUE; }

12. Parts of a basic MFC Program – 5a MainFrame.cpp This is where all the real work gets done #include "MainFrame.h" // Define the messages we will respond to and create the window BEGIN_MESSAGE_MAP (CMainFrame, CFrameWnd) // classname, base class //ON_WM_CREATE() //ON_WM_SHOWWINDOW() //ON_WM_ACTIVATE() ON_WM_MOVE() ON_WM_PAINT() END_MESSAGE_MAP()

13. Parts of a basic MFC Program – 5b MainFrame.cpp – part 2 CMainFrame::CMainFrame()// Explicit constructor { CString title = "DJ's WIndow"; Create (NULL /* classname*/, title, WS_OVERLAPPEDWINDOW, CRect (0, 0, 670, 300), NULL,/* parent window ptr*/ 0,/* ID */ NULL/* create context ptr - only if overriding the context */ ); }

14. Parts of a basic MFC Program – 5c void CMainFrame::OnPaint() {CPaintDC dc(this);// "this" is a handle for current window // dc is the "device context" for the window dc.TextOut(x, y, "hello"); // works for printers or displays common (this);// call common code and pass the context } void CMainFrame::OnMove() { } void CMainFrame::common (CWnd * wptr) { // have the window ptr (wptr), but not always using it }

15. Window, Dialog & Control classes Frame Window – CFrameWnd, CMenu View – – Represent client area of a frame – Show data, accept input Cview, CScrollView, form & record, control Dialog box (modal, modeless) – Cdialog, CDataExchange Control – – Attached to CFrameWnd or CMiniFrameWnd – Static, text, number, button, list, toolbar, misc Control bar

16. CFrameWnd Framework for a single-document interface Usage – Derive a class using CFrameWnd::Create – Add member variables for your data – Implement message handlers – Define a message map Specifies actions when the window gets a msg

17. Dialog boxes Modal – Requires user interaction – Blocks program operation until action completed – Mode errors can be caused by: Caps-lock or Insert key Focus stealing (user types but nothing happens) Modeless – No interaction required (e.g.; toolbar) Note: this happens a lot in Unix/Linux editor, "vi", because mode indicator can be "off".

18. Views Represent the client area of a frame window Associated with document class & CFrameWnd 2 types of document views – Cview - base class for app-specific views – CScrollView - base class for scrollable data CFormView, CRecordView, CHtmlEditView Control views – CCrtlView, CEditView, CCListView, CTreeView

19. GetWindowRect Win32API version BOOL WINAPI GetWindowRect ( HWND hWnd, LPRECT lpRect ); note: TWO parameters, lpRect is a struct MFC version: void GetWindowRect ( LPRECT lpRect ) const; note: one parameter, lpRect is a class (a Crect object)

20. Document/View Architecture Display of data should be independent of the data May need to have different ways to look at the data CDocument class holds the data CView manages display and UI 2 kinds of apps: – Single Document Interface – Multiple Document Interface

21. View Display of the data & a way to display it Frame window: contains a view of the data Multiple views possible But only ONE doc per View

22. tips SDI application – One frame window derived from class CFrameWnd. CFrameWnd This window is both: – main frame window – and document frame window. MDI application, the main frame window is derived from class CMDIFrameWnd, and the document frame windows, which are MDI child windows, are derived from class CMDIChildWnd.CMDIFrameWnd CMDIChildWnd