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5 <TITLE>wxWidgets 2 FAQ: General</TITLE>
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16 <b>wxWidgets 2 FAQ: General</b>
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21
22 <P>
23
24 See also <a href="faq.htm">top-level FAQ page</a>.
25 <hr>
26 <h3>List of questions in this category</h3>
27 <ul>
28 <li><a href="#whatis">What is wxWidgets?</a></li>
29 <li><a href="#licence">Can I use wxWidgets 2 for both proprietary projects, and GPL&#39;ed projects?</a></li>
30 <li><a href="#support">Is there support?</a></li>
31 <li><a href="#users">Who uses wxWidgets?</a></li>
32 <li><a href="#platforms">What platforms are supported by wxWidgets?</a></li>
33 <li><a href="#specific">How does wxWidgets support platform-specific features?</a></li>
34 <li><a href="#stl">Does wxWidgets use STL? or the standard string class?</a></li>
35 <li><a href="#richedit">Is there a rich edit/markup widget for wxWidgets?</a></ li>
36 <li><a href="#exceptions">How to use C++ exceptions with wxWidgets?</a></ li>
37 <li><a href="#dev">How is wxWidgets being developed?</a></li>
38 <li><a href="#distrib">How is wxWidgets distributed?</a></li>
39 <li><a href="#future">What are the plans for the future?</a></li>
40 <li><a href="#base">What is wxBase?</a></li>
41 <li><a href="#univ">What is wxUniversal?</a></li>
42 <li><a href="#jave">What about Java?</a></li>
43 <li><a href="#dotnet">What about .NET/Mono?</a></li>
44 <li><a href="#help">How can I help the project?</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'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_tools.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 undersirable 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 strenously 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's alternative to Java, supporting 'managed code',
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'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'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't proven its long-term viability yet (it'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'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's a good indication that
301 the market for a C++-based approach is still there. (Either that, or everyone'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.wxwindows.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
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