News

From: Julian Smart Date: Sat, 31 Jul 1999 09:20:44 +0000 (+0000) Subject: Added news and coding standards HTML files to CVS X-Git-Url: https://git.saurik.com/wxWidgets.git/commitdiff_plain/97979ddfbe4bc199c6b0389e352d6963c17c64a0?ds=inline Added news and coding standards HTML files to CVS git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3224 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775 --- diff --git a/docs/html/news.htm b/docs/html/news.htm new file mode 100644 index 0000000000..b6e44fb85d --- /dev/null +++ b/docs/html/news.htm @@ -0,0 +1,258 @@ + + + +News + + + + + + + + + + +

+ +News + +

+ +

May 27th, 1999

+ +

Beta 1 of wxWindows 2 for Mac has been released, thanks to Stefan Csomor's amazing efforts. +
Work continues on the development branch of wxWindows 2 for MSW, GTK and Motif. Vadim has been reworking the +MSW implementation to solve some internal design problems, as well as factoring out base classes to make +development easier. +
Work on consistent drag and drop support in GTK and MSW continues. +

+ +

March 1st, 1999

+ +wxWindows 2 launch day!

+ +

wxWindows 2 officially launched, after more than two years' development of +the API and ports to Windows, GTK and Motif (Mac to follow). +Download wxWindows 2. +

+ +

November 26th 1998

+ +

wxWindows 1.68E contains minor bug fixes and now compiles with MS VC++ 6.0, and +(hopefully) BC++ 5.0, as well as Cygwin b20. +
The latest wxWindows 2.0 alpha shows good progress +on the Motif port, with a tabbed MDI implementation, a nice wxToolBar class and most +major classes working. wxWindows 2.0 for Windows now works with VC++ 6.0, BC++ 5.0 and +Cygwin b20. There's a problem linking with Mingw32, I don't know why this is, perhaps +something to do with differences in the way pragmas are handled. +
There is also good progress with Stefan Csomor's wxMac 2.0: watch this space. A preview +is available here. +
Work is finally underway on a wxWindows IDE! +
Aleksandras Gluchovas is working on a docking window implementation and the results +are pretty impressive so far. Here's a screenshot; +source code is here and a WIN32 executable +is here. The source also includes +work on persistent storage classes. +

+ +

September 13th 1998

+ +

The main ftp site is now www.remstar.com/pub/wxwin, +since the AIAI site is no longer available for uploads. +

+ +

August 23rd 1998

+ +

wxGTK and wxMSW 2.0 progress continues apace. The API is being unified quite successfully, +and most of the samples now compile under both ports. +
We are looking for sponsorship of wxMotif 2.0. +

+ +

April 28th 1998

+ +

wxWindows 1.68C has been released. This mainly provides compatibility with Gnu-Win32 b19 +and Mingw32. +
wxWindows 2.0 beta 9 has been released. Again, this provides Gnu-Win32 b19/Mingw32 compatibility +plus a few small bug fixes. +

+ +

March 22nd 1998

+ +

The mailing list addresses have changed: please see the mailing list page +for details. You may need to re-subscribe if you subscribed since February 1998. +

+ +

January 5th 1998

+ +

Happy New Year! +
wxWindows 1.68B is available. +
wxWindows 2.0 has another port in progress - wxGTK, +by Robert Roebling (see also the information on the same page about Robert's FADE desktop +environment project). +
The Windows and Xt/Motif ports to 2.0 are progressing well. A large proportion of the documentation +has been done. One of the main things to resolve is how transformations (such as scaling +and translation) will be done in 2.0, but we're heading towards agreement. +
There is a new wxWindows Developers Site in preparation, for people developing ports of +wxWindows. There are newsgroups and a wxwin-developers mailing list. +
40 wxWindows CD-ROMs have been sold, mostly outside the U.K. +
Antonia Charlotte Smart was born on November 1st 1997. Naturally, she's as cute as her parents. +

+ +

August 13th 1997

+ +

Added Getting Started page for new users. +
There's a good review of wxWindows by Oliver Niedung and Stefan Gunther in +iX, a German computer magazine. +

+ +

July 24th 1997

+ +

wxWindows 1.67 released. +

+ +

July 22nd 1997

+ +

wxWindows 1.67 is nearly there... +
Check out Forty Thieves, a great card game +by Chris Breeze of Hitachi Europe Limited. +

+ +

July 16th 1997

+ +

Jobst Schmalenbach has set up Australian mirrors of the wxWindows ftp and Web sites: +please see the Mirrors page. +
Arthur Tetzlaff-Deas is starting to look afresh at a port of wxWindows 2.0 to +NeXTStep. This is more relevant now that the NeXT OS will be essential to the Apple Mac's future. +
The next release of wxWindows for Motif/XView/Windows should be within the next two weeks or so. I have abandoned +documentation in wxHelp form in favour of the much better quality HTML format, which I +will be including with the distribution from now on. +

+ +

July 7th 1997

+ +

For news on wxWindows 2.0 development, please see What's coming next? +- developments include DLL and experimental Netscape Plugin support. The estimate for a release +date has been put back to October 1997 - to be out of the way before Smart Jr. arrives in November... +
Negotiations with a U.S. company about development of wxWindows into a commercial product +fell through, since it was not possible to agree about the continuation of a version +of wxWindows that maintains the free, collaborative spirit that currently exists. +

+ +

May 18th 1997

+ +

wxWindows 2.0 development (mostly for the Windows platform) is on track thanks to funding for wxWin-related consultancy +- thank you to those concerned! This work is still on the free version of 2.0, although an additional +commercial version may be developed sometime in the future. Markus Holzem continues to generously donate +his spare time for Motif/Xt developments, and Greg Whitehead is looking into the Mac version of 2.0. +
Guilhem Lavaux has contributed a first version of +wxSocket, a set of classes for +network programming based on work by Andrew Davison. Currently this works on Motif/Xt and is coded but not yet tested +for Windows. The wxIPC classes on the UNIX side have been rewritten to take advantage of the new +classes. wxSocket is a great contribution that will be a part of wxWindows 2.0. Meanwhile, do check +it out and help Guilhem debug and develop it further. +
Other noteworthy contributions in recent weeks include a patch for using bitmap +masks on X for transparency +effects - another Lavaux effort! - plus thread classes +by Wolfram Gloger, updates to wxXt by Markus Holzem, +a start at OLE control support by Norbert Grotz, +an improved Winstall by Stefan Hammes, +and wxPreferences by Bart Jourquin +to simulate .ini files on UNIX.
+Check out the Contributions page for more. +

+ +

May 8th 1997

+ +

Hitachi Europe Limited have used wxWindows both to implement and to illustrate +their WebReuser tool - a link to their pages has been +added to the Applications page. +
Another interesting link in the Applications page is +WipeOut, a C++ integrated development +environment for Linux. +
Fixes to make wxWindows 1.66F work with VC++ 5.0 are in the +ports/msvc50 +directory. +

+ +

April 20th 1997

+ +

wxWindows is listed in the Scientific Applications on Linux index, +here. +
There is a new page for issues with the current release which I would +encourage you to read. +
The wxWindows Web pages can be switched to non-frames mode, for those who find frames irritating +(and who use browsers that don't implement Back properly :-)). +
The Contrib page has some new entries. +
wxWindows 2.0 progress is steady. +
Greg Whitehead is taking a look at what's involved for a Mac port of 2.0, possibly using MetroWerks' PowerPlant +classes to speed up development. +

+ +

March 13th 1997

+ +

Check out C-LAB's Lean Integration Platform written in wxWindows/wxLisp: it's +a multi-platform workflow tool. Nice Web pages! +
I've written some tips to help you code for easy porting to wxWindows 2.0. +
wxWin 2.0 progress: I've eliminated the need for the dreaded CTL3D library for Windows 95 applications. +New MDI classes are working, plus wxStatusBar, wxScrolledWindow. Markus is starting work on the Motif +port, with wxXt 2.0 as a second priority. But financial help to keep +the momentum going is needed! +

+ +

February 25th 1997

+ +

Yura Bidus (yari_b@automedi.com) has successfully adapted wxWindows 1.66B to compile as a DLL under +Borland C++. He will be patching 1.66F and investigating using VC++ for building the DLL. +
Early experiments indicate that application files using wxWindows 2.0 +and GNU-WIN32 will be at least twice as fast to compile as 1.66, due to elimination of base classes +and restructuring to avoid including windows.h. +

+ +

January 29th 1997

+ +

wxWindows 1.66F has been semi-released +for people to test before the official release. It works with GNU-WIN32, and contains miscellaneous bug fixes. +
ITA, Inc. have sent a debugged and +enhanced Mac port (building on 1.61). +
Markus Holzem and Julian Smart are designing wxWindows 2.0, which should make wxWindows into a force +to be reckoned with against other free and commercial libraries. The What's coming next? +page will shortly contain more details. +
The mailing lists are up and running again, with new subscription and discussion +list addresses. +

+ +

+ + + + + + diff --git a/docs/html/standard.htm b/docs/html/standard.htm new file mode 100644 index 0000000000..196224130c --- /dev/null +++ b/docs/html/standard.htm @@ -0,0 +1,780 @@ + + + wxWindows Programmer Style Guide + + + + + + + + + + + + +
+ +wxWindows Programmer Style Guide + +
+ +

+ +by Vadim Zeitlin

+ +This guide is intended for people who are (or intending to start) writing code +for wxWindows class library. + +

+The guide is separated into two parts: the first one addresses the general +compatibility issues and is not wxWindows-specific. The advises in this part +will hopefully help you to write programs which compile and run on greater +variety of platforms. The second part details the wxWindows code organization and +its goal it to make wxWindows as uniform as possible without imposing too +many restrictions on the programmer. +

+Acknowledgements: This guide is partly based on +C++ portability guide by David Williams. + +

General C++ Rules

New or not widely supported C++ features

Don't use C++ templates
Don't use C++ exceptions
Don't use RTTI
Don't use namespaces
Don't use STL
Don't declare variables inside for()
Don't use nested classes

General recommendations

No global variables with constructor
Turn on all warnings and eradicate them
Don't rely on sizeof(int) == 2...
No assignments in conditional expressions
Use #if 0 rather than comments to temporarily + disable blocks of code
Don't use extra semi-colons on top level

Unix/DOS differences

Use .cpp for C++ source file extension
Don't use backslash ('\\') in #includes
Avoid carriage returns in cross-platform code
Use only lower letter filenames
Terminate the files with a new-line

Style choices

Naming conventions: use m_ for members
Don't use void for functions without + arguments
Don't use const for non pointer/reference + arguments

+ +

wxWindows Rules

Files location and naming conventions

File locations
Include guards
Precompiled headers

File layout and indentation

wxWindows standard header
Indent your code with 4 spaces (no tabs!)
Order of parts in a class declarations

More about naming conventions

Use wx or WX prefix for all public symbols
Use WXDLLEXPORT with all classes/functions in + wxMSW/common code
Use Set/Get prefixes for accessors

Miscellaneous

Use forward declarations whenever possible
Use debugging macros

+ +

General C++ Rules

New or not widely supported C++ features

The usage of all features in this section is not recommended for one reason: they appeared in C++ relatively recently and are not yet +supported by all compilers. Moreover, when they're supported, there are +differences between different vendor's implementations. It's understandable that +you might love one (or all) of these features, but you surely can write C++ +programs without them. Where possible, workarounds to compensate for absence +of your favourite C++ abilities are indicated. +

Just to suppress any doubts that there are compilers which don't support +these new features, you can think about Win16 (a.k.a. Win 3.1) compilers, +none of which supports any feature from the list below. + +

Don't use C++ templates

+Besides the reasons mentioned above, template usage also makes the +program compile much slower (200%-300% is not uncommon) and their support +even in the compilers which have had it for a long time is far from perfect +(the best example is probably gcc). +

Workaround: The things you would like to use templates for are, +most commonly, polymorphic containers (in the sense that they can contain objects of +any type without compromising C++ type system, i.e. using void * +is out of question). wxWindows provides dynamic +arrays and lists which are sufficient in 99% of cases - please don't hesitate +to use them. Lack of template is not a reason to use static arrays or +type-less (passing by void *) containers. + +

Don't use C++ exceptions

+The C++ exception system is an error-reporting mechanism. Another reasons not to use it, +besides portability, are the performance penalty it imposes (small, but, at least for +current compilers, non-zero), and subtle problems with +memory/resource deallocation it may create (the place where you'd like to use +C++ exceptions most of all are the constructors, but you need to be very +careful in order to be able to do it). +

Workaround: there is no real workaround, of course, or the exceptions +wouldn't have been added to the language. However, there are several rules which +might help here:

+ +

Every function returns an integer (or at least boolean) error code. +
There is no such thing as a function that never fails - even if it can't + fail now, it might do it later, when modified to be more powerful/general. + Put the int or bool return type from the very beginning!
+
Every function you call may fail - check the return code! +
Never rely on the function's success, always test for a possible error.
+

Tell the user about the error, don't silently ignore them. +

Exceptions are always caught and, normally, processed when they're + caught. In the same manner, the error return code must always be processed + somehow. You may choose to ignore it, but at least tell the user that + something wrong happened using wxLogError or + wxLogWarning functions. All wxWindows + functions (must) log the error messages on failure - this can be disabled + by using wxLogNull object before calling it. +

Examples:

Wrong: +

+void ReadAddressBookFile(const wxString& strName)
+{
+  wxFile file;
+  
+  if ( !file.Open(strFile) )
+    return;
+  
+  ...process it...
+}
+

Correct: +

+// returns false if the address book couldn't be read
+bool ReadAddressBookFile(const wxString& strName)
+{
+  wxFile file;
+  
+  if ( !file.Open(strFile) ) {
+    // wxFile logged an error because file couldn't be opened which
+    // contains the system error code, however it doesn't know what
+    // this file is for and an error message "can't open $GLCW.ADB"
+    // can be quite confusing for the user. Here we say what we mean.
+    wxLogError("Can't read address book from '%s'!", 
+	       strName.c_str());
+    return false;
+  }
+  
+  ...process it...
+    
+  return true;
+}
+

+ or, if it's not an error if file doesn't exist (here we could just check + its existence, but let's suppose that there is no wxFile::Exists()) + we can also write: +

+// returns false if address book file doesn't exist
+bool ReadAddressBookFile(const wxString& strName)
+{
+  wxFile file;
+  
+  // start a block inside which all log messages are suppressed
+  {
+    wxLogNull noLog;
+    if ( !file.Open(strFile) )
+      return false;
+  }
+  
+  ...process it...
+  
+  return true;
+}
+

Don't use RTTI

+RTTI stands for Run-Time Type Information and there is probably no other +reason not to use it except the portability issue and the fact that it adds +sizeof(void *) bytes to any class having virtual functions (at least, +in the implementations I'm aware of). +

Workaround: use wxWindows RTTI system which allows you to do almost +everything which the new C++ RTTI, except that, of course, you have to use +macros instead of the (horrible looking, BTW) dynamic_cast. + +

Don't use namespaces

+This topic is subject to change with time, however for the moment all wxWindows +classes/functions live in the global namespace. +

Workaround: None. + +

Don't use STL

+STL is the new C++ standard library, proposing all kinds of template containers +and generic algorithm implementations. Templates are the heart (and almost +everything else) of the library, so its usage is out of question. Besides, even +with the compilers which do support templates, STL has many of its own problems, +there are many "not 100% standard compatible" vendor implementations, none of existing debuggers understands its +complicated data structures, ... the list can go on (almost) forever. +

Workaround: Use wxString, dynamic arrays and lists and other wxWindows +classes. wxString has many of the most often used functions of std::string STL +class (typedef to be precise). +

Don't declare variables inside for() +

+The scope of a variable declared inside for() statement changed several +years ago, however many compilers still will complain about second declaration +of i in the following code: +

+  for ( int i = 0; i < 10; i++ ) {
+    ...
+  }
+
+  ...
+
+  for ( int i = 0; i < 10; i++ ) {
+    ...
+  }
+

Workaround: write this instead: +

+  int i;
+  for ( i = 0; i < 10; i++ ) {
+    ...
+  }
+
+  ...
+
+  for ( i = 0; i < 10; i++ ) {
+    ...
+  }
+

Don't use nested classes

+Nested classes are, without doubt, a very good thing because they allow to hide +"private" (in the sense that they're used only inside the library) classes and, +generally, put the related things together. +

Unfortunately, some compilers have trouble understanding them, so we must +sacrifice the ideals of software design to get a working program in this case. +

Workaround: instead of +

+  // in the header
+  class PublicLibClass {
+  ...
+  private:
+    class PrivateLibClass { ... } m_object;
+  };
+

+  // in the header
+  class PrivateLibClass; // fwd decl
+  class PublicLibClass {
+  ...
+  private:
+   class PrivateLibClass *m_pObject;
+  };
+  
+  // in the .cpp file
+  class PrivateLibClass { ... };
+  
+  PublicLibClass::PublicLibClass()
+  {
+    m_pObject = new PrivateLibClass;
+    
+    ...
+  }
+  
+  PublicLibClass::~PublicLibClass()
+  {
+    delete m_pObject;
+  }
+

A nice side effect is that you don't need to recompile all the files +including the header if you change the PrivateLibClass declaration (it's +an example of a more general interface/implementation separation idea). +

General recommendations

+While the recommendations in the previous section may not apply to you if you're +only working with perfect compilers which implement the very newest directives of +C++ standard, this section contains compiler- (and language-) independent advice +which must be followed if you wish to write correct, i.e. working, programs. It +also contains some C/C++ specific remarks in the end which are less +important. +

No global variables with constructors

+In C++, the constructors of global variables are called before the +main() function (or WinMain() or any other program entry point) +starts executing. Thus, there is no possibility to initialize anything +before the constructor call. The order of construction is largely +implementation-defined, meaning that there is no guarantee that one global +object will be initialized before another one (except if they are both defined +in the same translation unit, i.e. .cpp file). Most importantly, no custom +memory allocation operators are installed at the moment of execution of global +variables constructors, so a (less restrictive) rule is that you should have +no global variables which allocate memory (or do anything else non-trivial) in +the constructor. Of course, if an object doesn't allocate memory in its constructor +right now, it may start making it later, so you can only be sure about this if +you don't use any variables of object (as opposed to simple: +int, ...) types. Example: currently, wxString doesn't allocate memory +in its default constructor, so you might think that having a global (initially) +empty wxString is safe. However, if wxString starts allocating some minimal +amount of memory in its default constructor (which doesn't look unreasonable), +you would have all kinds of problems with new +and delete operators (overloaded in wxWindows), especially because the first new called +is the standard one (before wxWindows overloads them) and delete will +be the overloaded operator. + +

Turn on all warnings and eradicate them

+Give the compiler a chance to help you - turn on all warnings! You should always +use the maximum available warning level of your compiler and understand and +correct each of them. If, for whatever reasons, a compiler gives a warning on +some perfectly legal line of code and you can't change it, please insert a +comment indicating it in the code. Most oftenly, however, all compiler warnings +may be avoided (not suppressed!) with minimal changes to your code. + +

Don't rely on sizeof(int) == 2...

+You should never assume any absolute constraints on data type sizes. Currently, +we have 16-bit, 32-bit and 64-bit machines and even inside each class data type +sizes are different. A small table illustrates it quite well: + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
Architecture/OS sizeof(short) sizeof(int) sizeof(long) sizeof(void *)
i386/Windows 3.1 2 2 4 2 or 4
i386/Windows 95 2 4 4 4
Merced/Win64 2 4 4 8
Alpha/Linux ??? ??? ??? ???
+ +

No assignments in conditional expressions

+Although close to the heart of many C programmers (I plead guilty), code like +classical if ( (c = getchar()) != EOF ) is bad because it prevents you +from enabling "assignment in conditional expression" warning (see also +above) warning which is helpful to detect common +mistypes like if ( x = 2 ) instead of if ( x == 2 ). + +

Use #if 0 rather than comments to temporarily + disable blocks of code

+If you have to temporarily disable some code, use +

+  #if 0 // VZ: I think this code is unneeded, it probably must be removed
+    ...
+  #endif // 0
+

+  /*
+    ...
+  */
+

/* ... */

...

Don't use extra semi-colons on top level

+Some compilers don't pay any attention to extra semicolons on top level, as in +

+  class Foo { };;
+

IMPLEMENT_something

Unix/DOS differences

+ Two operating systems supported by wxWindows right now are (different flavours +of) Unix and Windows 3.1/95/NT (although Mac, OS/2 and other ports exist/are +being developed as well). The main differences between them are summarized +here. + +

Use .cpp for C++ source file extension

+There is, unfortunately, no standard exceptions for C++ source files. Different +people use .C, .cc, .cpp, .cxx, .c++ and probably several others I forgot. Some +compilers don't care about extension, but there are also other ones which can't +be made to compile any file with "wrong" extension. Such compilers are very +common in DOS/Windows land, that's why the .cpp extension is the least likely to +cause any problems - it's the standard one under DOS and will probably be +accepted by any Unix compiler as well (any counter examples?). The extension +for the header files is .h. + +

Don't use backslash ('\\') in #includes

+Although it's too silly to mention, please don't use backslashes in +#include preprocessor statement. Even not all Windows compilers accept +it, without speaking about all other ones. + +

Avoid carriage returns in cross-platform code

+This problem will hopefully not arise at all, with CVS taking care of this +stuff, however it's perhaps not useless to remember that many Unix compilers +(including, but not limited to, gcc) don't accept carriage returns +(= = '\r') in C/C++ code. + +

Use only lower case filenames

+DOS/Windows 3.1 isn't case sensitive, Windows 95/NT are case preserving, but not +case sensitive. To avoid all kinds of problems with compiling under Unix (or +any other fully case-sensitive OS), please use only lower case letters in the +filenames. + +

Terminate the files with a new-line

+While DOS/Windows compilers don't seem to mind, their Unix counterparts don't +like files without terminating new-line. Such files also give a warning message +when loaded to vim (the Unix programmer's editor of choice :-)), so please think +about terminating the last line. +

Style choices

+ All wxWindows specific style guidelines are specified in the next +section, here are the choices which are not completely arbitrary, +but have some deeper and not wxWindows-specific meaning. + +

Naming conventions: use m_ for members

+It's extremely important to write readable code. One of the first steps in this +direction is the choice of naming convention. It may be quite vague or strictly +define the names of all the variables and function in the program, however it +surely must somehow allow the reader to distinguish between variable and +functions and local variables and member variables from the first glance. +

The first requirement is commonly respected, but for some strange reasons, the +second isn't, even if it's much more important because, after all, the immediate +context usually allows you to distinguish a variable from a function in +C/C++ code. On the other hand, you cannot say what x in the +following code fragment is: +

+  void Foo::Bar(int x_)
+  {
+    ...
+      
+    x = x_;
+    
+    ...
+  }
+

x = x_

The wxWindows naming convention gives you, the reader of the code, much more +information about x. In the code above you know that it's a local +variable because:

global variables are always prefixed with g_
member variables are always prefixed with m_
static variables are always prefixed with s_

Examples: +

+  extern int g_x; // of course, 'x' is not the best name for a global...
+
+  void Bar()
+  {
+    int x;
+  }
+
+  class Foo {
+    public:
+      void SetX(int x) { m_x = x; }
+    private:
+      int m_x;
+  };
+

SetX()

x

Foo::m_x

The prefixes can be combined to give ms_ and gs_ for static +member (a.k.a. class) variables and static global variables. +

The convention is, of course, completely worthless if it is not followed: +nothing like being sure that x is a local variable in the code fragment +above and discovering later the following lines in the header: +

+  class Foo {
+    ...
+    int x;  // I don't like wxWindows naming convention
+  };
+

Hungarian notation

type

Don't use void for functions without + arguments

+In ANSI C, void Foo() takes an arbitrary number of arbitrarily typed +arguments (although the form void Foo(...) is preferred) and void +Foo(void) doesn't take any arguments. In C++, however, the situation is +different and both declarations are completely equivalent. As there is no need +to write void in this situation, let's not write it - it can only be +confusing and create an impression that it really means something when it's not +at all the case. + +

Don't use const for non pointer/reference + arguments

+In both C and C++ an argument passed by value cannot be modified - or, more +precisely, if it is modified in the called function, only the local copy is +really changed, not the caller's variable. So, semantically speaking, there is +no difference between void Foo(int) and void Foo(const int). +However, the const keyword is confusing here, adds nothing to the code +and even cannot be removed if Foo() is virtual and overridden (because +the names are mangled differently). So, for arguments passed by value +you shouldn't use const. +

Of course, it doesn't apply to functions such as +void PrintMessage(const char *text) where const is mandatory. +

+ +

wxWindows rules

File location and naming conventions

File locations

+The wxWindows files for each supported platform have their own subdirectories +in "include" and "src". So, for example, there is "src/msw", "include/gtk" +etc. There are also two special subdirectories called "common" and +"generic". The common subdirectory contains the files which are platform +independent (wxObject, wxString, ...) and the generic one the generic +implementations of GUI widgets, i.e. those which use only other wxWindows +classes to implement them. For the platforms where the given functionality +cannot be implemented natively, the generic implementation is used and the native +one is used for the others. As I feel that it becomes a bit too confusing, +here is an example: wxMessageBox function is implemented natively under +Windows (where it just calls MessageBox API), but there is also a generic +implementation which is used under, for example, GTK. A generic class should +normally have a name that distinguishes it from any platform-specific implementation. +A #define will allow wxGenericMessageDialog to be wxMessageDialog on some +platforms, for example. + +

This scheme applies not only for the .cpp files, but also for the headers. +However, as the program using wxWindows should (ideally) not use any +"#ifdef <platform>" at all, the headers are always included with +"#include <wx/msgdlg.h>" (for example). This file, in turn, includes +the right header for given platform. Any new headers should conform to this +setup as well to allow including <wx/foo.h> on any platform.

+ +Note that wxWindows implementation files should use quotes when including wxWindows +headers, not angled brackets. Applications should use angled brackets. There +is a reason for it (can anyone remember what this is?). + +

Include guards

+To minimize the compile time C++ programmers often use so called include +guards: for example, in the header file foo.h you might have + +

+#ifndef _FOO_H_
+#define _FOO_H_
+
+... all header contents ...
+
+#endif
+ //_FOO_H_
+

+ +In this way, the header will only be included once for the compilation +of any .cpp (of course, it still will be included many times for the +compilation of the whole project, so it has nothing to do with precompiled +headers). wxWindows is no exception and also uses include guards which should use +the above form, except for top-level headers which include files with identical +names, in which case you should use _FOO_H_BASE_. + +

Precompiled headers

+The precompiled headers greatly (we're speaking about orders of hundreds of +percent here) reduce the compilation time. wxWindows uses them if the target +compiler supports them (it knows about MS Visual C++, Borland C++ and g++). +You should include all the headers included from only +inside "#if !USE_PRECOMP" to avoid unnecessary overhead in the case +when the precompiled headers are used.

+ +The start of a cpp implementation file after the heading might look like this:

+ +

+#ifdef __GNUG__
+#pragma implementation "bitmap.h"
+#endif
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+#pragma hdrstop
+#endif
+
+#ifndef WX_PRECOMP
+#include <stdio.h>
+#include "wx/setup.h"
+#include "wx/list.h"
+#include "wx/utils.h"
+#include "wx/app.h"
+#include "wx/palette.h"
+#include "wx/bitmap.h"
+#include "wx/icon.h"
+#endif
+
+#include "wx/msw/private.h"
+#include "assert.h"
+

+ + +

Any header file should containg the following lines: +

+#ifdef __GNUG__
+  #pragma interface "foo.h"
+#endif
+

+and the corresponding .cpp file: +

+#ifdef __GNUG__
+  #pragma  implementation "foo.h"
+#endif
+

for g++ compilation. +

+ +

File layout and indentation

wxWindows standard header

here

Indent your code with 4 spaces (no tabs!) +

Order of parts in a class declarations

+ +

More about naming conventions

Use wx or WX prefix for all public symbols. +wx should be used for functions and classes, WX for macros. +

Use WXDLLEXPORT with all classes/functions in + wxMSW/common code +The title says it all - every public (in the sense that it is not internal to +the library) function or class should have WXDLLEXPORT macro in its +declaration to allow compilation of wxWindows as shared library. For example:
+ +
```
+bool WXDLLEXPORT wxYield(void);
+class WXDLLEXPORT MyClass;  // (for forward declarations and real declarations)
+WXDLLEXPORT_DATA(extern wxApp*) wxTheApp;
+
```
+ +The reason for the strange syntax for data is that some compilers use different +keyword ordering for exporting data. + +
There also several other places where you should take care of shared +library case: all IMPLEMENT_xxx macros which are usually used in the +corresponding .cpp files must be taken inside +"#if !USE_SHARED_LIBRARY" and in the #if USE_SHARED_LIBRARY +case you should put them inside common/cmndata.cpp file. + +

Use Set/Get prefixes for accessors

+There is a convention in wxWindows to prefix the accessors (i.e. any simple, in +general, inline function which does nothing else except changing or returning +the value of a member variable) with either Set or Get. +

+ +

Miscellaneous

Use forward declarations whenever possible

+It's really a trivial piece of advice, but remember that using forward declarations +instead of including the header of corresponding class is better because not +only does it minimize the compile time, it also simplifies the dependencies +between different source files. +

On a related subject, in general, you should try not to include other +headers from a header file. + +

Use debugging macros

+wxWindows provides the debugging macros wxASSERT, wxFAIL and +wxCHECK_RET in file. Please use them as often as +you can - they will never do you any harm but can greatly simplify the bug +tracking both for you and for others. +

Also, please use wxFAIL_MSG("not implemented") instead of writing +stubs for not (yet) implemented functions which silently return incorrect +values - otherwise, a person using a not implemented function has no idea that +it is, in fact, not implemented. +

As all debugging macros only do something useful if the symbol +__DEBUG__ is defined, you should compile your programs in debug mode to profit +from them. +

+ +

+Please send any comments to Vadim Zeitlin. + + + + +

Architecture/OS	sizeof(short)	sizeof(int)	sizeof(long)	sizeof(void *)
i386/Windows 3.1	2	2	4	2 or 4
i386/Windows 95	2	4	4	4
Merced/Win64	2	4	4	8
Alpha/Linux	???	???	???	???