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4 <TITLE>wxWindows 2 for Windows FAQ</TITLE>
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15 wxWindows 2 for Windows FAQ
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21 <P>
22
23 See also <a href="faq.htm">top-level FAQ page</a>.
24 <hr>
25
26 <h3>Which Windows platforms are supported?</h3>
27
28 wxWindows 2 can be used to develop and deliver applications on Windows 3.1, Win32s,
29 Windows 95, Windows 98, and Windows NT. A Windows CE version is being looked into (see below).<P>
30
31 wxWindows 2 is designed to make use of WIN32 features and controls. However, unlike Microsoft,
32 we have not forgotten users of 16-bit Windows. Most features
33 work under Windows 3.1, including wxTreeCtrl and wxListCtrl using the generic implementation.
34 However, don't expect very Windows-95-specific classes to work, such as wxTaskBarIcon. The wxRegConfig
35 class doesn't work either because the Windows 3.1 registry is very simplistic. Check out the 16-bit
36 makefiles to see what other files have been left out.
37 <P>
38 16-bit compilation is supported under Visual C++ 1.5, and Borland BC++ 4 to 5.
39 <P>
40
41 wxWindows 2 for Windows will also compile on Unix with gcc using TWIN32 from <a href="http://www.willows.com" target=_top>Willows</a>,
42 although TWIN32 is still in a preliminary state. The resulting executables are
43 Unix binaries that work with the TWIN32 Windows API emulator.<P>
44
45 You can also compile wxWindows 2 for Windows on Unix with Cygwin or Mingw32, resulting
46 in executables that will run on Windows. So in theory you could write your applications
47 using wxGTK or wxMotif, then check/debug your wxWindows for Windows
48 programs with TWIN32, and finally produce an ix86 Windows executable using Cygwin/Mingw32,
49 without ever needing a copy of Microsoft Windows. See the Technical Note on the Web site detailing cross-compilation.<P>
50
51 <h3>What about Windows CE?</h3>
52
53 This is under consideration, though we need to get wxWindows Unicode-aware first.
54 There are other interesting issues, such as how to combine the menubar and toolbar APIs
55 as Windows CE requires. But there's no doubt that it will be possible, albeit
56 by mostly cutting down wxWindows 2 API functionality, and adding a few classes here
57 and there. Since wxWindows for 2 produces small binaries (less than 300K for
58 the statically-linked 'minimal' sample), shoehorning wxWindows 2 into a Windows CE device's limited
59 storage should not be a problem.<P>
60
61 <h3>What compilers are supported?</h3>
62
63 Please see the wxWindows 2 for Windows install.txt file for up-to-date information, but
64 currently the following are known to work:<P>
65
66 <ul>
67 <li>Visual C++ 1.5, 4.0, 5.0, 6.0
68 <li>Borland C++ 4.5, 5.0
69 <li>Borland C++Builder 1.0, 3.0
70 <li>Watcom C++ 10.6 (WIN32)
71 <li>Cygwin b20
72 <li>Mingw32
73 <li>MetroWerks CodeWarrior 4
74 </ul>
75 <P>
76
77 There is a linking problem with Symantec C++ which I hope someone can help solve.
78 <P>
79
80 <h3>Which is the best compiler to use with wxWindows 2?</h3>
81
82 It's partly a matter of taste, but I (JACS) prefer Visual C++ since the debugger is very
83 good, it's very stable, the documentation is extensive, and it generates small executables.
84 Since project files are plain text, it's easy for me to generate appropriate project files
85 for wxWindows samples.<P>
86
87 Borland C++ is fine - and very fast - but it's hard (impossible?) to use the debugger without using project files, and
88 the debugger is nowhere near up to VC++'s quality. The IDE isn't great.<P>
89
90 C++Builder's power isn't really used with wxWindows since it needs integration with its
91 own class library (VCL). For wxWindows, I've only used it with makefiles, in which case
92 it's almost identical to BC++ 5.0 (the same makefiles can be used).<P>
93
94 You can't beat Cygwin's price (free), and you can debug adequately using gdb. However, it's
95 quite slow to compile since it does not use precompiled headers.<P>
96
97 CodeWarrior is cross-platform - you can debug and generate Windows executables from a Mac, but not
98 the other way around I think - but the IDE is, to my mind, a bit primitive.<P>
99
100 Watcom C++ is a little slow and the debugger is not really up to today's standards.<P>
101
102 <h3>Is Unicode supported?</h3>
103
104 Not yet, although there are other internationalisation features.<P>
105
106 However, the issues surrounding Unicode support have been looked into so we know
107 what we need to do, and have some header files ready to use containing appropriate
108 type definitions. Just about every file in wxWindows will need changes, due to the
109 pervasive nature of characters and character arrays. Unicode support is needed
110 for the port to Windows CE (see above), and will probably be added in time for version 2.1.<P>
111
112 <h3>Can you compile wxWindows 2 as a DLL?</h3>
113
114 Yes (using the Visual C++ or Borland C++ makefile), but be aware that distributing DLLs is a thorny issue
115 and you may be better off compiling statically-linked applications, unless you're
116 delivering a suite of separate programs, or you're compiling a lot of wxWindows applications
117 and have limited hard disk space.<P>
118
119 With a DLL approach, and with different versions and configurations of wxWindows
120 needing to be catered for, the end user may end up with a host of large DLLs in his or her Windows system directory,
121 negating the point of using DLLs. Of course, this is not a problem just associated with
122 wxWindows!
123 <P>
124
125 <H3>How can I reduce executable size?</H3>
126
127 You can compile wxWindows as a DLL (see above, VC++/BC++ only at present). You should also
128 compile your programs for release using non-debugging and space-optimisation options, but
129 take with VC++ 5/6 space optimisation: it can sometimes cause problems.<P>
130
131 Statically-linked wxWindows 2 programs are smaller than wxWindows 1.xx programs, because of the way
132 wxWindows 2 has been designed to reduce dependencies between classes, and other
133 techniques. The linker will not include code from the library that is not (directly or
134 indirectly) referenced
135 by your application. So for example, the 'minimal' sample is less than 300KB using VC++ 6.<P>
136
137 If you want to distribute really small executables, you can
138 use <a href="http://www.icl.ndirect.co.uk/petite/" target=_top>Petite</a>
139 by Ian Luck. This nifty utility compresses Windows executables by around 50%, so your 500KB executable
140 will shrink to a mere 250KB. With this sort of size, there is reduced incentive to
141 use DLLs.<P>
142
143 <H3>Is wxWindows compatible with MFC?</H3>
144
145 There is a sample which demonstrates MFC and wxWindows code co-existing in the same
146 application. However, don't expect to be able to enable wxWindows windows with OLE-2
147 functionality using MFC.<P>
148
149 <H3>Why do I sometimes get bizarre crash problems using VC++ 5/6?</H3>
150
151 Some crash problems can be due to inconsistent compiler
152 options (and of course this isn't limited to wxWindows).
153 If strange/weird/impossible things start to happen please
154 check (dumping IDE project file as makefile and doing text comparison
155 if necessary) that the project settings, especially the list of defined
156 symbols, struct packing, etc. are exactly the same for all items in
157 the project. After this, delete everything (including PCH) and recompile.<P>
158
159 VC++ 5's optimization code seems to be broken and can
160 cause problems: this can be seen when deleting an object Dialog
161 Editor, in Release mode with optimizations on. If in doubt,
162 switch off optimisations, although this will result in much
163 larger executables. It seems possible that the library can be created with
164 strong optimization, so long as the application is not strongly
165 optimized. For example, in wxWindows project, set to 'Minimum
166 Size'. In Dialog Editor project, set to 'Customize: Favor Small
167 Code' (and no others). This will then work.<P>
168
169 <H3>How are the wxWindows makefiles edited under Windows?</H3>
170
171 As of wxWindows 2.1, there is a new system written by Vadim Zeitlin, that
172 generates the makefiles from templates using tmake.<P>
173
174 Here are Vadim's notes:<P>
175
176 <blockquote>
177 To use these new makefiles, you don't need anything (but see below).
178 However, you should NOT modify them because these files will be
179 rewritten when I regenerate them using tmake the next time. So, if
180 you find a problem with any of these makefiles (say, makefile.b32)
181 you'll need to modify the corresponding template (b32.t in this
182 example) and regenerate the makefile using tmake.<P>
183
184 tmake can be found at
185 <a href="http://www.troll.no/freebies/tmake.html" target=_new>www.troll.no/freebies/tmake.html</a>.
186 It's a Perl5 program and so it needs Perl (doh). There is a binary for
187 Windows (available from the same page), but I haven't used it, so
188 I don't know if it works as flawlessly as "perl tmake" does (note
189 for people knowing Perl: don't try to run tmake with -w, it won't
190 do you any good). Using it extremely simple: to regenerate makefile.b32
191 just go to distrib/msw/tmake and type<P>
192
193 <pre>tmake -t b32 wxwin.pro -o ../../src/msw/makefile.b32</pre><P>
194
195 The makefiles are untested - I don't have any of Borland, Watcom or
196 Symantec and I don't have enough diskspace to recompile even with
197 VC6 using makefiles. The new makefiles are as close as possible to the
198 old ones, but not closer: in fact, there has been many strange things
199 (should I say bugs?) in some of makefiles, some files were not compiled
200 without any reason etc. Please test them and notify me about any problems.
201 Better yet, modify the template files to generate the correct makefiles
202 and check them in.<P>
203
204 The templates are described in tmake ref manual (1-2 pages of text)
205 and are quite simple. They do contain some Perl code, but my Perl is
206 primitive (very C like) so it should be possible for anybody to make
207 trivial modifications to it (I hope that only trivial modifications
208 will be needed). I've tagged the ol makefiles as MAKEFILES_WITHOUT_TMAKE
209 in the cvs, so you can always retrieve them and compare the new ones,
210 this will make it easier to solve the problems you might have.<P>
211
212 Another important file is filelist.txt: it contains the list of all
213 files to be compiled. Some of them are only compiled in 16/32 bit mode.
214 Some other are only compiled with some compilers (others can't compile
215 them) - all this info is contained in this file.<P>
216
217 So now adding a new file to wxWindows is as easy as modifying filelist.txt
218 (and Makefile.ams for Unix ports) and regenerating the makefiles - no
219 need to modify all files manually any more.<P>
220
221 Finally, there is also a file vc6.t which I use myself: this one
222 generates a project file for VC++ 6.0 (I didn't create vc5.t because
223 I don't need it and can't test it, but it should be trivial to create
224 one from vc6.t - probably the only things to change would be the
225 version number in the very beginning and the /Z option - VC5 doesn't
226 support edit-and=continue). This is not an officially supported way
227 of building wxWindows (that is, nobody guarantees that it will work),
228 but it has been very useful to me and I hope it will be also for
229 others. To generate wxWindows.dsp run<P>
230
231 <pre>tmake -t vc6 wxwin.pro -o ../../wxWindows.dsp</pre><P>
232
233 Then just include this project in any workspace or open it from VC IDE
234 and it will create a new workspace for you.<P>
235
236 If all goes well, I'm planning to create a template file for Makefile.ams
237 under src/gtk and src/motif and also replace all makefiles in the samples
238 subdirectories with the project files from which all the others will be
239 generated. At least it will divide the number of files in samples
240 directory by 10 (and the number of files to be maintained too).
241 </blockquote>
242
243 <P>
244
245 <H3>How do you use VC++'s memory leak checking instead of that in wxWindows?</H3>
246
247 Vadim Zeitlin:
248
249 <pre>
250 On the VC++ level, it's just the matter of calling _CrtSetDbgFlag() in the very
251 beginning of the program. In wxWindows, this is done automatically when
252 compiling with VC++ in debug mode unless wxUSE_GLOBAL_MEMORY_OPERATORS or
253 __NO_VC_CRTDBG__ are defined - this check is done in wx/msw/msvcrt.h which
254 is included from app.cpp which then calls wxCrtSetDbgFlag() without any
255 #ifdefs.
256
257 This works quite well: at the end of the program, all leaked blocks with their
258 malloc count are shown. This number (malloc count) can be used to determine
259 where exactly the object was allocated: for this it's enough to set the variable
260 _crtBreakAlloc (look in VC98\crt\srs\dbgheap.c line 326) to this number and
261 a breakpoint will be triggered when the block with this number is allocated.
262
263 For simple situations it works like a charm. For something more complicated
264 like reading uninitialized memory a specialized tool is probably better...
265
266 Regards,
267 VZ
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