Semester overview CSC 4111 Software Engineering Lab

1. Semester overviewCSC 4111 Software Engineering Lab Winter 2010

2. Schedule • Lab 1 – syllabus, tools needed • Lab 2 – Technologies in NotePad++ • Lab 3 – using Subversion • Lab 4 – example of a software change • Lab 5 – Change request 1 • Lab 6 – using Visio • Lab 7 – group meeting. Q/A about projects

3. Schedule • Lab 8 – CR1 due + change request 2 • Lab 9 – unit testing • Lab 10 – group meeting. Q/A about project • Lab 11 – CR 2 due + change request 3 • Lab 12 – refactoring • Lab 13 – group meeting. Q/A about project • Lab 14 – CR3 due + overview

4. Technologies in NotePad++CSC 4111 Software Engineering Lab Winter 2010

5. Classical Flow of a Program • The flow is sequential from beginning to end (program executes top-bottom). • The user is invoked by the program. • The user enters input when the program dictates so. • The path varies depending on the input and conditions.

6. Event Driven Development (EDD) • EDD – a new paradigm • Hollywood Principle: "Don't call us; we'll call you." • The user decides the flow of the program, by performing a particular action • The action that the user performs is translated to an event (keystroke, mouse click, command for windows repaint, etc.) • The event is handled in the system by event handlers • Most common use of EDD: graphical user interfaces (GUIs) • Windows programs: Event-driven programming model.

7. The Handlers Pattern

8. Handlers Pattern: Event: • a software message that indicates something has happened, such as a keystroke or mouse click Dispatcher: • takes each event and analyzes it to determine its type • sends each event to a handler that can handle events of that type. • its logic includes an event loop, as it has to process a stream of input events Handler: • A procedure specialized in handling a specific type of events

9. Sequence of events • The application paints several user interface objects (e.g.: buttons, text areas, menus, etc.) • The application waits in a piece of code (event-loop) for the user to do something • The user does something to the objects on the screen (e.g.: clicks on a button - > the mouse click is an event) • The user interface object updates its appearance on the screen and calls a pre-arranged function in the system, which contains the code that implements the action for the GUI object

10. Win32 Application • WndProc – dispatcher for each window • Standard Messages: • WM_CREATE, • WM_SIZE, • WM_COMMAND, • WM_MENUSELECT • resource.h contains the definitions of the new user messages • IDM_FILE_NEW • IDM_FILE_OPEN • IDM_EDIT_COPY

11. How to send and receive messages • ::SendMessage function takes 4 parameters: • LRESULT SendMessage(          HWND hWnd,     UINT Msg,     WPARAM wParam,     LPARAM lParam ); • hWnd – handler to the window (mainwindow, combobox, dialogbox, checkbox, radiobutton, etc.) • Msg – the message to send • Depending on the message the value in the window can read or written • wParam, lParam – parameters of the message • Variables to store the value, value to be stored • Use SendMessage when you are dealing with dialog windows related to the menu

12. Windows application • Hello world #include <windows.h> int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, intnCmdShow) { MessageBox(NULL, "Goodbye, cruel world!", "Note", MB_OK); return 0; } WinMain – the equivalent of the function main in Console applications HINSTANCE hInstance - Handle to the programs executable module (the .exe file in memory) HINSTANCE hPrevInstance - Always NULL for Win32 programs. LPSTR lpCmdLine - The command line arguments as a single string. NOT including the program name. intnCmdShow - An integer value which may be passed to ShowWindow(). We'll get to this later.

13. Task 1 – simple window • Create an Empty project in Visual Studio 2008 • Create a new cpp file in the project • Add the code from task1.cpp • Compile and run

14. Create and register your window • Let’s create a real window • Step 1: Register the Window Class • Step 2: Create the Window • Step 3: The Message Loop • Step 4: The Window Procedure

15. Task 2 • Create an Empty project in Visual Studio 2008 • Create a new cpp file in the project • Add the code from task2.cpp • Compile and run

16. Windows Queue Windows Queue

17. Message loop • A message is an integer value. • Look for their definition in the header files #define IDM_FILE_NEW 40001 // Step 3: The Message Loop while(GetMessage(&Msg, NULL, 0, 0) > 0) { TranslateMessage(&Msg); DispatchMessage(&Msg); }

18. Task 3 – find the message loop in NotePad++ • Which file contains the message loop in Notepad++?

19. Receiving messages • All the messages are received using the Window procedure // Step 4: the Window Procedure LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) { switch(msg) { case WM_CLOSE: DestroyWindow(hwnd); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hwnd, msg, wParam, lParam); } return 0; }

20. Task 4 - Window Procedure • The window procedure is called for each message (CALLBACK) • Each window has its own window procedure • Task 4: add the following message in the window from task 2 case WM_LBUTTONDOWN: { char szFileName[MAX_PATH]; HINSTANCE hInstance = GetModuleHandle(NULL); GetModuleFileName(hInstance, szFileName, MAX_PATH); MessageBox(hwnd, szFileName, "This program is:", MB_OK | MB_ICONINFORMATION); } • Task 5: Name at least 5 files in Notepad++ where a Window procedure is defined?

21. Sending messages • ::SendMessage function takes 4 parameters: • LRESULT SendMessage(          HWND hWnd,     UINT Msg,     WPARAM wParam,     LPARAM lParam ); • hWnd – handler to the window (mainwindow, combobox, dialogbox, checkbox, radiobutton, etc.) • Msg – the message to send • Depending on the message the value in the window can read or written • wParam, lParam – parameters of the message • Variables to store the value, value to be stored • Use SendMessage when you are dealing with dialog windows related to the menu

22. What parameters to use • Select the text in a combobox: • ::SendMessage(hCombo, CB_SETCURSEL, (WPARAM)-1, 0) • ::SendMessage(hCombo, CB_SETEDITSEL, 0, MAKELPARAM(0, -1)); • Task 6: check in MSDN what parameters to use for the two messages above

23. How to show a window • After the window is created, it is not visible • Use showWindow or display to show a main window • You can select and work with other windows in the same tim • use doDialog to show a dialog, • The window will be displayed on top, no other window can be selected • ::ShowWindow(::GetDlgItem(_hSelf, IDCMARKALL), isEnable?SW_HIDE:SW_SHOW); • _aboutDlg.doDialog();

24. How to enable a window • ::EnableWindow(::GetDlgItem(_hSelf, IDBOOLOR), FALSE); • EnableWindows takes 2 parameters • The first parameter is a reference to a window • The second parameter is a boolean value • GetDlgItem returns a reference to the window (controller) with the given id from the parent window _hself • IDBOOLOR – is a radio button created by one of you • _hself – refers to findReplaceDlg window

25. What to submit • Task 1 – Hello World ( 20 points) • Task 2 – Simple Window (20 points ) • Task 3 – find the message loop in NotePad++ (20 points) • Task 4: add the following message in the window from task 2 ( 20 points) • Task 5: Name at least 5 files in Notepad++ where a Window procedure is defined? (10 points) • Task 6: check in MSDN what parameters to use for the two messages above (10 points) Extra credit (20 points) • Task 7: How many parameters do you have to specify for the message SCI_FINDCOLUMN? What is the meaning of these parameters? What does the following function call return?

26. Submit the lab! • Complete the tasks by January 27th – 7:30PM • Send all the answers as a zip file trough blackboard • If you missed the class contact the instructor

27. Extra slides Winter 2010

28. Scintilla library • Contains functions which allow the user to avoid the usage of SendMessage function • Function “execute” from the class ScintillaEditView LRESULT execute(UINT Msg, WPARAM wParam=0, LPARAM lParam=0) const { return _pScintillaFunc(_pScintillaPtr, static_cast<int>(Msg), static_cast<int>(wParam), static_cast<int>(lParam)); }; • The user only need to specify the message intcaretPos = execute(SCI_GETCURRENTPOS);

29. Demo • A simple application that uses Scintilla library

30. Other tips • Menus, windows, GUI in general are defined in *.rc files • Use search in files to grep for string in these files • cxx and hpp are extensions of C++ files, they are equivalent with cpp and header files • http://www.scintilla.org/ScintillaDoc.html

31. NotePad++ example – how to find the maker type During concept location I found the message: SCI_INDICATORVALUEAT The change request was to go the next marked area I looked in scintilla.h and I found the message: SCI_INDICATORVALUEAT Question: How to use this message Execute(SCI_INDICATORVALUEAT) always returns the same number (1)

32. How to find the implementation of a message in Scintilla project • Search for SCI_INDICATORVALUEAT in SciLexer project. Found: case SCI_INDICATORVALUEAT: return pdoc->decorations.ValueAt(wParam, lParam); • Both wParam and lParam are used • The implementation of the method ValueAt intDecorationList::ValueAt(int indicator, int position) { Decoration *deco = DecorationFromIndicator(indicator); if (deco) { return deco->rs.ValueAt(position); } return 0; }

33. Getting the value   int currentposition = _pEditView->execute(SCI_GETCURRENTPOS); LRESULT style1 = _pEditView->execute(SCI_INDICATORVALUEAT, SCE_UNIVERSAL_FOUND_STYLE_EXT1, currentposition); If the current position is marked with style 1 the value is of style1 is 1, otherwise it is 0 Task 7: How many parameters do you have to specify for the message SCI_FINDCOLUMN? What is the meaning of these parameters? What does the following function call return? (*_ppEditView)->execute(SCI_FINDCOLUMN, i, j)