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  15 <b>wxWidgets 2 FAQ: General</b>
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  21 <P>
  22
  23 See also <a href="faq.htm">top-level FAQ page</a>.
  24 <hr>
  25 <h3>List of questions in this category</h3>
  26 <ul>
  27 <li><a href="#whatis">What is wxWidgets?</a></li>
  28 <li><a href="#licence">Can I use wxWidgets 2 for both proprietary projects, and GPL&#39;ed projects?</a></li>
  29 <li><a href="#support">Is there support?</a></li>
  30 <li><a href="#users">Who uses wxWidgets?</a></li>
  31 <li><a href="#platforms">What platforms are supported by wxWidgets?</a></li>
  32 <li><a href="#specific">How does wxWidgets support platform-specific features?</a></li>
  33 <li><a href="#stl">Does wxWidgets use STL? or the standard string class?</a></li>
  34 <li><a href="#richedit">Is there a rich edit/markup widget for wxWidgets?</a></ li>
  35 <li><a href="#exceptions">How to use C++ exceptions with wxWidgets?</a></ li>
  36 <li><a href="#dev">How is wxWidgets being developed?</a></li>
  37 <li><a href="#distrib">How is wxWidgets distributed?</a></li>
  38 <li><a href="#future">What are the plans for the future?</a></li>
  39 <li><a href="#base">What is wxBase?</a></li>
  40 <li><a href="#univ">What is wxUniversal?</a></li>
  41 <li><a href="#jave">What about Java?</a></li>
  42 <li><a href="#dotnet">What about .NET/Mono?</a></li>
  43 <li><a href="#help">How can I help the project?</a></li>
  44 <li><a href="#newport">How do I start a new port?</a></li>
  45 </ul>
  46 <hr>
  47
  48 <H3><a name="whatis">What is wxWidgets?</a></H3>
  49
  50 wxWidgets is a class library that allows you to compile graphical C++ programs on a range of
  51 different platforms. wxWidgets defines a common API across platforms, but uses the native graphical user interface (GUI) on each platform,
  52 so your program will take on the native &#39;look and feel&#39; that users are familiar with.<P>
  53
  54 Although GUI applications are mostly built programmatically, there are several dialog editors to help
  55 build attractive dialogs and panels. Robert Roebling&#39;s <a href="http://www.roebling.com">wxDesigner</a>
  56 and Anthemion Software&#39;s <a href="http://www.anthemion.co.uk/dialogblocks/" target=_new>DialogBlocks</a>
  57 are two commercial examples, but there are others: see the <a href="lnk_tool.htm">Useful Tools</a> page.<P>
  58
  59 You don&#39;t have to use C++ to use wxWidgets: there is a <a href="http://wxpython.org">Python interface</a> for wxWidgets 2,
  60 and also a <a href="http://wxperl.sourceforge.net" target=_top>Perl interface</a>.
  61 <P>
  62
  63 <h3><a name="licence">Can I use wxWidgets 2 for both proprietary (commercial) projects, and GPL&#39;ed projects?</a></h3>
  64
  65 Yes. Please see the <a href="newlicen.htm">licence</a> for details, but basically
  66 you can distribute proprietary binaries without distributing any source code, and neither will wxWidgets
  67 conflict with GPL code you may be using or developing with it.
  68 <P>
  69 The conditions for using wxWidgets 2 are the same whether you are a personal, academic
  70 or commercial developer.
  71 <P>
  72
  73 <h3><a name="support">Is there support?</a></h3>
  74
  75 No official support, but the mailing list is very helpful and some people say that
  76 wxWidgets support is better than for much commercial software. The developers are
  77 keen to fix bugs as soon as possible, though obviously there are no guarantees.
  78 <P>
  79
  80 <H3><a name="users">Who uses wxWidgets?</a></H3>
  81
  82 Many organisations - commercial, government, and academic - across the
  83 world. It&#39;s impossible to estimate the true number of users, since
  84 wxWidgets is obtained by many different means, and we cannot monitor
  85 distribution. The mailing list contains around 300-400 entries which is
  86 quite large for a list of this type.<P>
  87
  88 See <a href="users.htm">Users</a> for a list of some users and their applications, and
  89 also <A href="feedback.htm">Feedback</a> for comments.<P>
  90 Our highest-profile user yet is industry veteran and Lotus Corp. founder Mitch Kapor
  91 and his <a href="http://www.osafoundation.org" target=_new>Open Source Applications Foundation</a>.
  92 <P>
  93
  94 <H3><a name="platforms">What platforms are supported by wxWidgets 2?</a></H3>
  95
  96 <ul>
  97 <li>Windows 3.1, Windows 95/98, Windows NT, Windows 2000, Windows ME.
  98 <li>Linux and other Unix platforms with GTK+.
  99 <li>Unix with Motif or the free Motif clone Lesstif.
 100 <li>Mac OS.
 101 <li>Embedded platforms are being investigated. See the <a href="wxuniv.htm">wxUniversal</a> project.
 102 <li>An OS/2 port is in progress, and you can also compile wxWidgets for GTK+ or Motif
 103 on OS/2.
 104 </ul>
 105 <P>
 106
 107 <H3><a name="specific">How does wxWidgets 2 support platform-specific
 108 features?</a></H3>
 109
 110 This is a hotly-debated topic amongst the developers. My own philosophy
 111 is to make wxWidgets as platform-independent as possible, but allow in a
 112 few classes (functions, window styles) that are platform-specific.
 113 For example, Windows metafiles and Windows 95 taskbar icons have
 114 their own classes on Windows, but nowhere else. Because these classes
 115 are provided and are wxWidgets-compatible, it doesn&#39;t take much
 116 coding effort for an application programmer to add support for
 117 some functionality that the user on a particular platform might otherwise
 118 miss. Also, some classes that started off as platform-specific, such
 119 as the MDI classes, have been emulated on other platforms. I can imagine
 120 that even wxTaskBarIcon may be implemented for Unix desktops one day.
 121 <P>
 122
 123 In other words, wxWidgets is not a &#39;lowest common denominator&#39; approach,
 124 but it will still be possible to write portable programs using the
 125 core API. Forbidding some platform-specific classes would be a stupid
 126 approach that would alienate many potential users, and encourage
 127 the perception that toolkits such as wxWidgets are not up to the demands
 128 of today&#39;s sophisticated applications.<P>
 129
 130 Currently resources such as bitmaps and icons are handled in a platform-specific
 131 way, but it is hoped to reduce this dependence in due course.<P>
 132
 133 Another reason why wxWidgets 2 is not a &#39;lowest common denominator&#39; toolkit is that
 134 some functionality missing on some platform has been provided using generic,
 135 platform-independent code, such as the wxTreeCtrl and wxListCtrl classes.<P>
 136
 137 <H3><a name="stl">Does wxWidgets use STL? or the standard string class?</a></H3>
 138
 139 No. This is a much-discussed topic that has (many times) ended with the conclusion that it is in
 140 wxWidgets&#39; best interests to avoid use of templates. Not all compilers can handle
 141 templates adequately so it would dramatically reduce the number of compilers
 142 and platforms that could be supported. It would also be undesirable to make
 143 wxWidgets dependent on another large library that may have to be downloaded and installed.
 144 In addition, use of templates can lead to executable bloat, which is something
 145 wxWidgets 2 is strenuously trying to avoid.<P>
 146
 147 The standard C++ string class is not used, again because it is not available to all compilers,
 148 and it is not necessarily a very efficient implementation. Also, we retain more flexibility
 149 by being able to modify our own string class. Some compatibility with the string class
 150 has been built into wxString.<P>
 151
 152 There is nothing to stop an application using templates or the string class for its own
 153 purposes. With wxWidgets debugging options on, you may find you get errors when including
 154 STL headers. You can work around it either by switching off memory checking,
 155 or by adding this to a header before you include any STL files:<P>
 156
 157 <PRE>
 158 &#35;ifdef new
 159 &#35;undef new
 160 &#35;endif
 161 </PRE>
 162
 163 <P>
 164
 165
 166 <H3><a name="richedit">Is there a rich edit/markup widget for wxWidgets 2?</a></H3>
 167
 168 These are the possibilities so far:<P>
 169
 170 <ul>
 171 <li>See <a href="http://www.scintilla.org" target=_top>www.scintilla.org</a> for
 172 a very nice syntax-highlighting editor widget. Robin Dunn has written a wxWidgets wrapper
 173 for this widget, available in the wxWidgets distribution under contrib/src/stc.
 174 <li>If you only need to display marked-up information, rather than edit it,
 175 then wxHTML will suit your needs. wxHTML is built into wxWidgets - please see the reference
 176 manual for details, and samples/html.
 177 <li>There are rich edit widgets in both WIN32 and GTK+, but there is currently
 178 no wxWidgets wrapper for these (but text attribute functions are being added in the wxWidgets 2.3.x series).
 179 </ul>
 180
 181 <P>
 182
 183 <h3><a name="exceptions">How to use C++ exceptions with wxWidgets?</a></h3>
 184
 185 wxWidgets library itself is unfortunately <i>not</i> exception-safe (as its
 186 initial version predates, by far, the addition of the exceptions to the C++
 187 language). However you can still use the exceptions in your own code and use
 188 the other libraries using the exceptions for the error reporting together with
 189 wxWidgets.
 190
 191 <p>
 192 There are a few issues to keep in mind, though:
 193 <ul>
 194     <li>You shouldn&#39;t let the exceptions propagate through wxWidgets code,
 195         in particular you should always catch the exceptions thrown by the
 196         functions called from an event handler in the handler itself and not
 197         let them propagate upwards to wxWidgets.
 198
 199     <li>You may need to ensure that the compiler support for the exceptions is
 200         enabled as, considering that wxWidgets itself doesn&#39;t use the
 201         exceptions and turning their support on results in the library size
 202         augmentation of 10% to 20%, it is turned off by default for a few
 203         compilers. Moreover, for gcc (or at least its mingw version) you must
 204         also turn on the RTTI support to be able to use the exceptions, so you
 205         should use <tt>--disable-no_rtti --disable-no_exceptions</tt> options
 206         when configuring the library (attention to the double negation).
 207 </ul>
 208
 209 <p>
 210
 211 <H3><a name="dev">How is wxWidgets being developed?</a></H3>
 212
 213 We are using the <a href="cvs.htm">CVS</a> system to develop and maintain wxWidgets. This allows
 214 us to make alterations and upload them instantly to the server, from
 215 which others can update their source.<P>
 216
 217 To build source from CVS, see the file BuildCVS.txt in the top-level wxWidgets distribution
 218 directory.<P>
 219
 220 <H3><a name="distrib">How is wxWidgets distributed?</a></H3>
 221
 222 By ftp, and via the <a href="cdrom2.htm">wxWidgets CD-ROM</a>.
 223 <P>
 224 If you are feeling adventurous, you may also check out the sources directly
 225 from <a href="cvs.htm">cvs</a>.
 226 <p>
 227
 228 <H3><a name="future">What are the plans for the future?</a></H3>
 229
 230 Currently we&#39;re working too hard on getting wxWidgets finished (are GUI toolkits ever
 231 finished?) to think very far ahead. However, we know we want to make wxWidgets as robust
 232 and well-publicised as possible. We also want to aim for better platform-independence of
 233 resources such as icons and bitmaps, standardising on PNG and XPM for all platforms.<P>
 234
 235 Other possibilities include: DCOM/CORBA compatibility; a wxWidgets book;
 236 <a href="http://wxworkshop.sourceforge.net/">wxWorkshop</a>, an IDE;
 237 other platforms, especially embedded systems; other interface abilities such as speech output.<P>
 238
 239 We will investigate the possibility of compiler or operating system vendors bundling wxWidgets with
 240 their product.<P>
 241
 242 The high-level goal of wxWidgets is to be thought of as the number one C++ framework,
 243 for virtually any platform. Move over, MFC!<P>
 244
 245 <h3><a name="base">What is wxBase?</a></h3>
 246
 247 wxBase is a subset of wxWidgets comprised by the non-GUI classes. It includes
 248 wxWidgets container and primitive data type classes (including wxString,
 249 wxDateTime and so on) and also useful wrappers for the operating system objects
 250 such as files, processes, threads, sockets and so on. With very minor
 251 exceptions wxBase may be used in exactly the same way as wxWidgets but it
 252 doesn&#39;t require a GUI to run and so is ideal for creating console mode
 253 utilities or server programs. It is also possible to create a program which can
 254 be compiled either as a console application (using wxBase) or a GUI one (using
 255 a full featured wxWidgets port).
 256
 257 <H3><a name="univ">What is wxUniversal?</a></H3>
 258
 259 The main difference between wxUniversal-based ports (such as wxX11, wxMGL) and other ports (such as wxMSW, wxGTK+, wxMac)
 260 is that wxUniversal implements all controls (or widgets) in
 261 wxWidgets itself thus allowing to have much more flexibility (for example, support for
 262 themes even under MS Windows). It also means that it is now much easier to
 263 port wxWidgets to a new platform as only the low-level classes must be ported
 264 which make for a small part of the library.
 265 <p>
 266 You may find more about wxUniversal <a href=wxuniv.htm>here</a>.
 267
 268 <H3><a name="jave">What about Java?</a></H3>
 269
 270 The Java honeymoon period is over :-) and people are realising that it cannot
 271 meet all their cross-platform development needs. We don&#39;t anticipate a major threat
 272 from Java, and the level of interest in wxWidgets is as high as ever.<P>
 273
 274 <H3><a name="dotnet">What about .NET/Mono?</a></H3>
 275
 276 Microsoft is spending a lot on promoting the .NET initiative, which
 277 is a set of languages, APIs and web service components for Windows.
 278 Ximian has started an open source version of .NET, mostly for Linux.
 279 C&#35; is Microsoft&#39;s alternative to Java, supporting &#39;managed code&#39;,
 280 garbage collection and various other Java-like language features.<P>
 281
 282 Although this may be attractive to some developers, there
 283 is a variety of reasons why the .NET/Mono combination is unlikely
 284 to make wxWidgets redundant. Please note that the following comments
 285 are Julian Smart&#39;s opinions.<P>
 286
 287 <ol>
 288 <li>Not everyone wants or needs net services.
 289 <li>C++ will be used for a long time to come; compared with C++, C&#35; is a recent development and its future is not certain.
 290 <li>Mono Forms may only target Winelib (at least to begin with), so the end result is not as native as
 291 wxWidgets (I&#39;m aware there is GTK&#35; for use with the C&#35; language).
 292 <li>C&#35; is usually byte-compiled and therefore slower. Plus, .NET adds a layer of overhead to the client computer
 293 that wxWidgets does not require.
 294 <li>Mono hasn&#39;t proven its long-term viability yet (it&#39;s a complex system of components); wxWidgets is ready now.
 295 <li>You may not wish to buy into Microsoft marketing spin and APIs.
 296 <li>Microsoft may at some point sue developers of non-Microsoft .NET implementations. After all,
 297 platform-independence is not in Microsoft&#39;s interest.
 298 <li>.NET might never be implemented on some platforms, especially Mac and embedded variants of Linux.
 299 <li>wxPython and other language variants provide further reasons for wxWidgets to continue.
 300 <li>The same issue exists for Qt: if Qt sales remain strong, it&#39;s a good indication that
 301 the market for a C++-based approach is still there. (Either that, or everyone&#39;s turning to wxWidgets!)
 302 </ol>
 303
 304 There is nothing to stop folk from developing a C&#35; version of the wxWidgets API;
 305 we already have bindings to Python, Perl, JavaScript, Lua, Basic, and Eiffel.
 306 Update: a <a href="http://wxnet.sourceforge.net/" target=_new>wx.NET</a> project is now in progress.
 307
 308 <P>
 309
 310 <H3><a name="help">How can I help the project?</a></H3>
 311
 312 Please check out the <a href="http://www.wxwidgets.org/develop2.htm">Community</a> pages,
 313 in particular the <a href="projects.htm">suggested projects</a>, and
 314 mail the developers&#39; mailing list with your own suggestions.<P>
 315
 316 <H3><a name="newport">How do I start a new port?</a></H3>
 317
 318 Please subscribe to the wx-dev <a href="maillst2.htm">developers&#39; mailing list</a> and
 319 ask if anyone else is interested in helping with the port, or
 320 has specific suggestions. Also please read the <a href="standard.htm">coding standards</a>.
 321
 322 <P>
 323 Each port consists of a platform-specific part (e.g. src/msw, include/wx/msw),
 324 a generic set of widgets and dialogs for when the port doesn&#39;t support
 325 them natively (src/generic, include/wx/generic) and the common code
 326 that all ports use (src/common, include/wx). By browsing the source
 327 you should get a good idea of the general pattern.<P>
 328
 329 Take a port that most closely matches your port, and strip out
 330 the implementation so you have a skeleton port that compiles. Ask on wx-dev
 331 first for the wxStubs port - however, any such predefined skeleton
 332 port may be out of date, so make a judgement on whether to use it.
 333 Perhaps it will still save you time to clean up wxStubs, and
 334 others may benefit from this too.<P>
 335
 336 You will need to define a symbol for the new port, e.g. __WXXBOX__.
 337 Look at files such as wx/defs.h, wx/wxchar.h for areas where you&#39;ll
 338 need to add to existing conditionals to set up wide character
 339 support and other issues. If the GUI runs on a Unix variant,
 340 define the __UNIX__ variable in your makefile.<P>
 341
 342 Then you can start implementing the port, starting with
 343 wxWindow, wxTopLevelWindow, wxFrame, wxDialog so you
 344 can get the minimal sample running as soon as possible.<P>
 345
 346 If GDI objects (wxPen, wxBrush, etc.) are not concepts in your
 347 native GUI, you may wish to use very generic versions of
 348 some of these - see the wxX11 port.<P>
 349
 350 Consider using the wxUniversal widget set as a quick way
 351 to implement wxWidgets on your platform. You only need
 352 to define some basic classes such as device contexts,
 353 wxWindow, wxTopLevelWindow, GDI objects etc. and
 354 the actual widgets will be drawn for you. See wxX11,
 355 wxMGL, and wxMSW/Univ for sample wxUniversal ports.<P>
 356
 357 To begin with, you can use whatever makefiles or project
 358 files work for you. Look at existing makefiles to see what
 359 generic/common/Unix files need to be included. Later, you&#39;ll want to integrate support
 360 for your port into configure (Unix-like systems and gcc under Windows),
 361 and bakefile (for other makefiles on Windows).<P>
 362
 363 Submit your port as patches via SourceForge; you might
 364 wish to separate it into one patch that touches common headers
 365 and source files, and another containing the port-specific code, to make
 366 it much easier for us to review and apply the patches.<P>
 367
 368 Good luck!
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