Linux RAD/GUI Development

1. Linux RAD/GUI Development • Kylix • Rapid Application Development (RAD), GUI Development for Linux from Borland by Leland Brode ELB Software elbrode2@attbi.com

2. Linux GUI Development • Presentation Outline • Backgroundon GUI Development • Overview of Kylix • Demo GUI Tools • Demo Delphi • Demo Kylix by Leland Brode ELB Software elbrode2@attbi.com

3. Linux GUI Development • Kylix • RAD/GUI tool for Linux • Port of Delphi for Windows • Runs on Linux • Builds, compiles native Linux applications • Cross platform – Windows/Linux

4. GUI Dev Background • Windows 3.0 – 1990 • Generates Messages • Basic, COBOL, C • All Text • Visual Basic – 1991 • First GUI Dev Tool • Event Handlers – code that runs before or after an Event • Draw window instead of code it • Most widely used language “Visual Basic 6 Bible” - Smith Whistler, & Marquis

5. GUI Dev Background • Other GUI Dev Tools • PowerBuilder • Visual Age • Digitalk, ParcPlace Smalltalk • Forte ( now at Sun) • Visual C++ • Borland C++ • Borland Delphi • Borland C++Builder • -------------------------- • Visual Café - Java • JBuilder - Java

6. Linux Developement • GNU Linux Toolkit • GCC • Compiles C, C++, Objective C, Fortran • Handles Front-ends for Pascal, Modula-3, Ada • Distributed with Linux • Perl, Shell scripting

7. Linux Developement • Qt Class Library • C++ • Cross Platform • Qt/Windows • Qt/X11 (Linux, Solaris, HPUX, AIX, etc) • Qt/Mac • GPL – Free for non-commercial apps • Qt was used to build KDE • from Trolltech in Norway • www.trolltech.com

8. Linux Development • Qt Class Libray • Qwidgetbase class • Event Handlers • mousePressEvent (QMouseEvent &); • mouseMove Event (… • mousePressEvent (… • enterEvent (… • Class QMouseEvent : public Qevent { • public: • int x(); • int y(); • int button(); • int state(); “Linux Programming Unleashed” – Kurt Wall - SAMS

9. Linux Development • Open Source IDE’s • KDevelop – www.kdevelop.org • KDE Studio – www.thekompany.com/projects/kdestudio • Code Crusader – www.newplanetsoftware.com • VDK Builder – vdkbuilder.sourceforge.net • Source-Navigator – sources.redhat.com/sourcenav “C/C++ Users Journal”, March 2001 – www.cuj.com

10. Delphi Background • Borland’s Delphi = • Pascal, plus • Borland’s implementation of OO in Pascal, plus • GUI IDE, plus • Visual Component Library (VCL) - encapsulates Windows controls

11. Delphi • Pascal • Pascal dev by Niklas Wirth (Swiss, 1970) • Versions: U of C San Diego, Borland • Borland’s Turbo Pascal 1.0 - ? • Turbo Pascal 3.0 for DOS - 1985 • Object Extensions to Pascal 5.5 - ? • Turbo Pascal for Windows - 1991 • Delphi - OO Pascal – 1995 • polymorphism, inheritance, encapsulation http://www.engin.umd.umich.edu/CIS/course.des/cis400/index.html http://www.emsps.com/oldtools/borpasv.htm

12. Delphi • GUI Integrated Development Environment • Based on Visual Basic model

13. Delphi • IDE • project manager • keeps track of all source files for a project • code editor • code completion • GUI form designer • integrated debugger • watch variables • change variables • breakpoints • step through code

14. Kylix • Port of Delphi to Linux • OO Pascal • Delphi IDE • native Linux compiler • Class Library - CLX • Object wrappers for Qt widgets • Borland chose Qt over GTK+ • Delphi’s VCL re-engineered to CLX

15. Kylix • Class Libraries • CLX is to Kylix • VCL is to Delphi, C++Builder • MFC is to Visual C++ • Qt is to KDE • GTK is to GNOME • CLX runs on Linux and Windows

16. Delphi • VCL Class Library • Object wrappers for Windows Controls TObject | TControl __ | | TForm TButton

17. Kylix • CLX Class Library • Object wrappers for Qt Widgets TObject | TControl __ | | TForm Tbutton • CLX also in Delphi 6, and C++Bldr for cross platform

18. Kylix • Pascal Language • Source File = Unit • Units -> compile, link -> executable • code - .pas file • form - .dfm file ( each form has a .pas file )

19. Kylix • Pascal Language • Data types • Integer – 2147483648 to 2147483647 • Cardinal 0 to 4,294,967,785 • Byte 0 to 255 • Double floating point • Currency • Arrays – • MyArray : array[0..10] of Integer; // fixed • MyArray : array of Integer; // dynamic • SetLength(MyArray, length); // allocates memory for dynamic array • MyArray[length-1] := 1,024 // assignment

20. Kylix • Pascal Language • String – dynamic • Concat, Copy, Delete, Insert, Length, Pos, SetLength • Pointers • Exceptions • Try-except (same as try-catch in java, c++) • File IO • function – returns value • procedure – no return value

21. Kylix • Pascal Language - function function Factorial(Number : Cardinal): Int64; var N : Cardinal; begin Result := 1; for N := 2 to Number do Result := Result * N; end;

22. Kylix • Pascal Language – class definition type TAccount = class private fNumber : Cardinal; fBalance : Currency; public procedure WithDraw(Amount : Currency); end; TSavingsAccount = class (TAccount) private fReturnCheck : Boolean end; TCertificateof Deposit = class(TSavingsAccount) private fTerm : Cardinal; end;

23. Kylix • Pascal Language– use classes var CD1, CD2 : TAccount; begin CD1 := TCertificateofDeposit.Create; CD2 := TCertificateofDeposit.Create; … CD1.WithDraw(100.00); … … CD1.Free; CD2.Free; end;

24. Kylix • Pascal Language – Records and Arrays type PersonType = record LastName : String[10]; FirstName : String[10]; EmployeeNumber : Integer; end; { Persontype } MyArrayType = array [1..5] of PersonType; var PersonArray : MyArrayType; begin PersonArray[1].FirstName := ‘Donald’; PersonArray[1].LastName := ‘Duck’; …

25. Kylix • Pascal Language – Components and Arrays var ButtonArray : array of TButton; i, Num : integer; begin Num :=0; for i := 0 to Self.ComponentCount –1 do // ‘Self’ same as ‘this’ in C++ if Self.Components[i] is TButton then begin Inc(Num); SetLength(ButtonArray, Num); ButtonArray[Num-1] := TButton(Components[i]); end; end;

26. Kylix • Pascal Language – Comparison Pascal… var i : Integer; begin i := 1; C++… int i; i = 1; Perl… my $i; $i = 1;

27. Kylix • Pascal Language – Comparison

28. Kylix • Pascal Language – Comparison Pascal… while i < 100 do Inc(i); C++… while (i < 100) i++; Perl… while ($i < 100) { $i++;}

29. Kylix • Pascal Language – Comparison Pascal… for i := 0 to 100 do begin if i = 50 then Break; end; C++… for( i = 0; i <= 100; i++) if( i == 50) break; Perl… for( $i = 0; $ i <= 100; $i++) { if( $i == 50) last; }

30. Kylix • Qt • access to all Qt Widget public Events and Properties • Libc • access to all ‘libc’ functions

31. Kylix • GUI Applications • Database Applications • Console Applications • Web Server Applications

32. Kylix • Linux Multiprocessing apps • separate memory, communicate via file system • Linux Multithreading apps • same memory, share resources • TThread base class

33. Kylix • GUI Applications - (CLX TForm class) • Form1.Canvas.Brush.Color := clRed; • or := RGB(255, 0, 0); • Form1.Canvas.Rectangle(10, 10, 100, 100); • Form1.Canvas.Pen.color := clBlack; • Form1.Canvas.Pen.Width := 2; • Form1.Canvas.MoveTo(0, 20); // draw line • Form1.Canvas.LineTo(60, 20); // draw line • Form1.Canvas.Font.Name := ‘Arial’; • Form1.Canvas.Font.Size := 24; • Form1.Canvas.TextOut(30,1, ‘Hello World’); // write text

34. Kylix • Database Applications • db : TClientDataSet • db.FileName := ‘/xxx/nnn/yyy’; • db.Open; • db.Locate(‘EmpNum’, ‘124433’, []); • mystring := db.FieldValues[‘LastName’];

35. Kylix • Database Applications • db : TSQLDataSet • db.CommandText := ‘select * from ….’; • db.Open;

36. Kylix • Database Applications • data aware controls • automatically fill in data value from database • automatically update data value to database • controls can be ‘Active’ while building form

37. Kylix • Web Applications - raw CGI or - TWebApplication | TCGIApplication

38. Kylix • Kylix Versions • Kylix 1, 2, 3 (I am using 2) • Kylix 1, 2 – Delphi (Pascal) • Kylix 3 – add C++ Builder (C++) • Kylix Enterprise - Web, Middleware objects, Database objects • Kylix Professional - Database objects • Kylix Open Edition – Build open source apps licensed under GNU General Public License

39. Kylix • Technical Requirements – Kylix 2 • Pentium 400 Mhz ( I am using 366 Mhz) • 128MB RAM ( I am using 192MB) • 175MB disk space • Red Hat 6.2 or higher (I am using 7.2, Kernel 2.4.7) • SuSE 7.0 or higher

40. Kylix • Kylix Download • http://www.borland.com/products/downloads/download_kylix.html# • Kylix 3 currently available • Kylix 2 ??

41. Kylix • FreeCLX Project • Open Source CLX Class Library • available at SourceForge.net • includes BaseCLX, VisualCLX, and DataCLX classes (brings full functionality to Kylix Open Edition ?) • lack of detailed information on FreeCLX

42. Kylix • Bibliography • “Visual Basic Bible”, Smith, Whistler, & Marquis • “Delphi in a Nutshell”, Ray Lischer, O’Reilly • “Linux Programming Unleashed”, Kurt Wall, SAMS • “Object Pascal Language Guide”, Borland Delphi 3 Documentation • “Teach Yourself Delphi in 21 Days”, Osier, Grobman, & Batson, SAMS • “Kylix: The Professional Developer’s Guide and Reference”, Jon Shemitz, Apress • “Mastering Kylix 2”, Cantu & Barbini, SYBEX • “Borland Kylix Developer’s Guide”, Calvert, Calvert, Kaster, & Swart, SAMS • “In the Trenches”, by Dale Fuller, LINUX Magazine, January 2002 • Product Review of Kylix 2, LINUX Magazine, May 2002 • “Kylix vs. gcc Development” http://community.borland.com/article/0,1410,28555,00.html • “Technical Overview of the Kylix Compiler” http://community.borland.com/article/0,1410,28561,00.html • “Apache Development with Kylix” http://community.borland.com/article/0,1410,28556,00.html • Kylix and Qt, excerpts form Kylix newsgroup http://community.borland.com/article/0,1410,21850,00.html • Kylix newsgroup – “borland.public.kylix,non-technical”

43. Kylix • product demo…