git.saurik.com Git - wxWidgets.git/blame_incremental

... / ...

Commit	Line	Data
	1
	2	<HTML>
	3
	4	<HEAD>
	5	<TITLE>wxWidgets FAQ: General</TITLE>
	6	</HEAD>
	7
	8	<BODY BGCOLOR=#FFFFFF TEXT=#000000 VLINK="#00376A" LINK="#00529C" ALINK="#313063">
	9
	10	<font face="Arial, Lucida Sans, Helvetica">
	11
	12	<table width=100% border=0 cellpadding=3 cellspacing=0>
	13	<tr>
	14	<td bgcolor="#004080" align=left height=24 background="images/bluetitlegradient.gif">
	15	<font size=+1 face="Arial, Lucida Sans, Helvetica" color="#FFFFFF">
	16	<b>wxWidgets FAQ: General</b>
	17	</font>
	18	</td>
	19	</tr>
	20	</table>
	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 for both proprietary projects, and GPL'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	<!--
	40	<li><a href="#future">What are the plans for the future?</a></li>
	41	-->
	42	<li><a href="#base">What is wxBase?</a></li>
	43	<li><a href="#univ">What is wxUniversal?</a></li>
	44	<li><a href="#jave">What about Java?</a></li>
	45	<li><a href="#dotnet">What about .NET/Mono?</a></li>
	46	<li><a href="#help">How can I help the project?</a></li>
	47	<li><a href="#newport">How do I start a new port?</a></li>
	48	</ul>
	49	<hr>
	50
	51	<H3><a name="whatis">What is wxWidgets?</a></H3>
	52
	53	wxWidgets is a class library that allows you to compile graphical C++ programs on a range of
	54	different platforms. wxWidgets defines a common API across platforms, but uses the native graphical user interface (GUI) on each platform,
	55	so your program will take on the native 'look and feel' that users are familiar with.<P>
	56
	57	Although GUI applications are mostly built programmatically, there are several dialog editors to help
	58	build attractive dialogs and panels. Robert Roebling's <a href="http://www.roebling.com">wxDesigner</a>
	59	and Anthemion Software's <a href="http://www.anthemion.co.uk/dialogblocks/" target=_new>DialogBlocks</a>
	60	are two commercial examples, but there are others: see the <a href="lnk_tool.htm">Useful Tools</a> page.<P>
	61
	62	You don't have to use C++ to use wxWidgets: there is a <a href="http://wxpython.org">Python interface</a> for wxWidgets,
	63	and also a <a href="http://wxperl.sourceforge.net" target=_top>Perl interface</a>.
	64	<P>
	65
	66	<h3><a name="licence">Can I use wxWidgets for both proprietary (commercial) projects, and GPL'ed projects?</a></h3>
	67
	68	Yes. Please see the <a href="newlicen.htm">licence</a> for details, but basically
	69	you can distribute proprietary binaries without distributing any source code, and neither will wxWidgets
	70	conflict with GPL code you may be using or developing with it.
	71	<P>
	72	The conditions for using wxWidgets are the same whether you are a personal, academic
	73	or commercial developer.
	74	<P>
	75
	76	<h3><a name="support">Is there support?</a></h3>
	77
	78	No official support, but the mailing list is very helpful and some people say that
	79	wxWidgets support is better than for much commercial software. The developers are
	80	keen to fix bugs as soon as possible, though obviously there are no guarantees.
	81	<P>
	82
	83	<H3><a name="users">Who uses wxWidgets?</a></H3>
	84
	85	Many organisations - commercial, government, and academic - across the
	86	world. It's impossible to estimate the true number of users, since
	87	wxWidgets is obtained by many different means, and we cannot monitor
	88	distribution. The mailing list contains around 300-400 entries which is
	89	quite large for a list of this type.<P>
	90
	91	See <a href="users.htm">Users</a> for a list of some users and their applications, and
	92	also <A href="feedback.htm">Feedback</a> for comments.<P>
	93	Our highest-profile user yet is industry veteran and Lotus Corp. founder Mitch Kapor
	94	and his <a href="http://www.osafoundation.org" target=_new>Open Source Applications Foundation</a>.
	95	<P>
	96
	97	<H3><a name="platforms">What platforms are supported by wxWidgets?</a></H3>
	98
	99	<ul>
	100	<li>Windows 3.1, Windows 95/98, Windows NT, Windows 2000, Windows ME.
	101	<li>Linux and other Unix platforms with GTK+.
	102	<li>Unix with Motif or the free Motif clone Lesstif.
	103	<li>Mac OS.
	104	<li>Embedded platforms are being investigated. See the <a href="wxuniv.htm">wxUniversal</a> project.
	105	<li>An OS/2 port is in progress, and you can also compile wxWidgets for GTK+ or Motif
	106	on OS/2.
	107	</ul>
	108	<P>
	109
	110	<H3><a name="specific">How does wxWidgets support platform-specific
	111	features?</a></H3>
	112
	113	This is a hotly-debated topic amongst the developers. My own philosophy
	114	is to make wxWidgets as platform-independent as possible, but allow in a
	115	few classes (functions, window styles) that are platform-specific.
	116	For example, Windows metafiles and Windows 95 taskbar icons have
	117	their own classes on Windows, but nowhere else. Because these classes
	118	are provided and are wxWidgets-compatible, it doesn't take much
	119	coding effort for an application programmer to add support for
	120	some functionality that the user on a particular platform might otherwise
	121	miss. Also, some classes that started off as platform-specific, such
	122	as the MDI classes, have been emulated on other platforms. I can imagine
	123	that even wxTaskBarIcon may be implemented for Unix desktops one day.
	124	<P>
	125
	126	In other words, wxWidgets is not a 'lowest common denominator' approach,
	127	but it will still be possible to write portable programs using the
	128	core API. Forbidding some platform-specific classes would be a stupid
	129	approach that would alienate many potential users, and encourage
	130	the perception that toolkits such as wxWidgets are not up to the demands
	131	of today's sophisticated applications.<P>
	132
	133	Currently resources such as bitmaps and icons are handled in a platform-specific
	134	way, but it is hoped to reduce this dependence in due course.<P>
	135
	136	Another reason why wxWidgets is not a 'lowest common denominator' toolkit is that
	137	some functionality missing on some platform has been provided using generic,
	138	platform-independent code, such as the wxTreeCtrl and wxListCtrl classes.<P>
	139
	140	<H3><a name="stl">Does wxWidgets use STL? or the standard string class?</a></H3>
	141
	142	No. This is a much-discussed topic that has (many times) ended with the conclusion that it is in
	143	wxWidgets' best interests to avoid use of templates. Not all compilers can handle
	144	templates adequately so it would dramatically reduce the number of compilers
	145	and platforms that could be supported. It would also be undesirable to make
	146	wxWidgets dependent on another large library that may have to be downloaded and installed.
	147	In addition, use of templates can lead to executable bloat, which is something
	148	wxWidgets is strenuously trying to avoid.<P>
	149
	150	The standard C++ string class is not used, again because it is not available to all compilers,
	151	and it is not necessarily a very efficient implementation. Also, we retain more flexibility
	152	by being able to modify our own string class. Some compatibility with the string class
	153	has been built into wxString.<P>
	154
	155	There is nothing to stop an application using templates or the string class for its own
	156	purposes. With wxWidgets debugging options on, you may find you get errors when including
	157	STL headers. You can work around it either by switching off memory checking,
	158	or by adding this to a header before you include any STL files:<P>
	159
	160	<PRE>
	161	#ifdef new
	162	#undef new
	163	#endif
	164	</PRE>
	165
	166	<P>
	167
	168
	169	<H3><a name="richedit">Is there a rich edit/markup widget for wxWidgets?</a></H3>
	170
	171	These are the possibilities so far:<P>
	172
	173	<ul>
	174	<li>See <a href="http://www.scintilla.org" target=_top>www.scintilla.org</a> for
	175	a very nice syntax-highlighting editor widget. Robin Dunn has written a wxWidgets wrapper
	176	for this widget, available in the wxWidgets distribution under contrib/src/stc.
	177	<li>If you only need to display marked-up information, rather than edit it,
	178	then wxHTML will suit your needs. wxHTML is built into wxWidgets - please see the reference
	179	manual for details, and samples/html.
	180	<li>There are rich edit widgets in both WIN32 and GTK+, but there is currently
	181	no wxWidgets wrapper for these (but text attribute functions are being added in the wxWidgets 2.3.x series).
	182	</ul>
	183
	184	<P>
	185
	186	<h3><a name="exceptions">How to use C++ exceptions with wxWidgets?</a></h3>
	187
	188	wxWidgets library itself is unfortunately <i>not</i> exception-safe (as its
	189	initial version predates, by far, the addition of the exceptions to the C++
	190	language). However you can still use the exceptions in your own code and use
	191	the other libraries using the exceptions for the error reporting together with
	192	wxWidgets.
	193
	194	<p>
	195	There are a few issues to keep in mind, though:
	196	<ul>
	197	<li>You shouldn't let the exceptions propagate through wxWidgets code,
	198	in particular you should always catch the exceptions thrown by the
	199	functions called from an event handler in the handler itself and not
	200	let them propagate upwards to wxWidgets.
	201
	202	<li>You may need to ensure that the compiler support for the exceptions is
	203	enabled as, considering that wxWidgets itself doesn't use the
	204	exceptions and turning their support on results in the library size
	205	augmentation of 10% to 20%, it is turned off by default for a few
	206	compilers. Moreover, for gcc (or at least its mingw version) you must
	207	also turn on the RTTI support to be able to use the exceptions, so you
	208	should use <tt>--disable-no_rtti --disable-no_exceptions</tt> options
	209	when configuring the library (attention to the double negation).
	210	</ul>
	211
	212	<p>
	213
	214	<H3><a name="dev">How is wxWidgets being developed?</a></H3>
	215
	216	We are using the <a href="cvs.htm">CVS</a> system to develop and maintain wxWidgets. This allows
	217	us to make alterations and upload them instantly to the server, from
	218	which others can update their source.<P>
	219
	220	To build source from CVS, see the file BuildCVS.txt in the top-level wxWidgets distribution
	221	directory.<P>
	222
	223	<H3><a name="distrib">How is wxWidgets distributed?</a></H3>
	224
	225	By ftp, and via the <a href="cdrom2.htm">wxWidgets CD-ROM</a>.
	226	<P>
	227	If you are feeling adventurous, you may also check out the sources directly
	228	from <a href="cvs.htm">cvs</a>.
	229	<p>
	230
	231	<!--
	232	<H3><a name="future">What are the plans for the future?</a></H3>
	233
	234	TODO
	235
	236	<p>
	237
	238	-->
	239
	240	<h3><a name="base">What is wxBase?</a></h3>
	241
	242	wxBase is a subset of wxWidgets comprised by the non-GUI classes. It includes
	243	wxWidgets container and primitive data type classes (including wxString,
	244	wxDateTime and so on) and also useful wrappers for the operating system objects
	245	such as files, processes, threads, sockets and so on. With very minor
	246	exceptions wxBase may be used in exactly the same way as wxWidgets but it
	247	doesn't require a GUI to run and so is ideal for creating console mode
	248	utilities or server programs. It is also possible to create a program which can
	249	be compiled either as a console application (using wxBase) or a GUI one (using
	250	a full featured wxWidgets port).
	251
	252	<H3><a name="univ">What is wxUniversal?</a></H3>
	253
	254	The main difference between wxUniversal-based ports (such as wxX11, wxMGL) and other ports (such as wxMSW, wxGTK+, wxMac)
	255	is that wxUniversal implements all controls (or widgets) in
	256	wxWidgets itself thus allowing to have much more flexibility (for example, support for
	257	themes even under MS Windows). It also means that it is now much easier to
	258	port wxWidgets to a new platform as only the low-level classes must be ported
	259	which make for a small part of the library.
	260	<p>
	261	You may find more about wxUniversal <a href=wxuniv.htm>here</a>.
	262
	263	<H3><a name="jave">What about Java?</a></H3>
	264
	265	The Java honeymoon period is over :-) and people are realising that it cannot
	266	meet all their cross-platform development needs. We don't anticipate a major threat
	267	from Java, and the level of interest in wxWidgets is as high as ever.<P>
	268
	269	<H3><a name="dotnet">What about .NET/Mono?</a></H3>
	270
	271	Microsoft is spending a lot on promoting the .NET initiative, which
	272	is a set of languages, APIs and web service components for Windows.
	273	Ximian has started an open source version of .NET, mostly for Linux.
	274	C# is Microsoft's alternative to Java, supporting 'managed code',
	275	garbage collection and various other Java-like language features.<P>
	276
	277	Although this may be attractive to some developers, there
	278	is a variety of reasons why the .NET/Mono combination is unlikely
	279	to make wxWidgets redundant. Please note that the following comments
	280	are Julian Smart's opinions.<P>
	281
	282	<ol>
	283	<li>Not everyone wants or needs net services.
	284	<li>C++ will be used for a long time to come; compared with C++, C# is a recent development and its future is not certain.
	285	<li>Mono Forms may only target Winelib (at least to begin with), so the end result is not as native as
	286	wxWidgets (I'm aware there is GTK# for use with the C# language).
	287	<li>C# is usually byte-compiled and therefore slower. Plus, .NET adds a layer of overhead to the client computer
	288	that wxWidgets does not require.
	289	<li>Mono hasn't proven its long-term viability yet (it's a complex system of components); wxWidgets is ready now.
	290	<li>You may not wish to buy into Microsoft marketing spin and APIs.
	291	<li>Microsoft may at some point sue developers of non-Microsoft .NET implementations. After all,
	292	platform-independence is not in Microsoft's interest.
	293	<li>.NET might never be implemented on some platforms, especially Mac and embedded variants of Linux.
	294	<li>wxPython and other language variants provide further reasons for wxWidgets to continue.
	295	<li>The same issue exists for Qt: if Qt sales remain strong, it's a good indication that
	296	the market for a C++-based approach is still there. (Either that, or everyone's turning to wxWidgets!)
	297	</ol>
	298
	299	There is nothing to stop folk from developing a C# version of the wxWidgets API;
	300	we already have bindings to Python, Perl, JavaScript, Lua, Basic, and Eiffel.
	301	Update: a <a href="http://wxnet.sourceforge.net/" target=_new>wx.NET</a> project is now in progress.
	302
	303	<P>
	304
	305	<H3><a name="help">How can I help the project?</a></H3>
	306
	307	Please check out the <a href="http://www.wxwidgets.org/develop2.htm">Community</a> pages,
	308	in particular the <a href="projects.htm">suggested projects</a>, and
	309	mail the developers' mailing list with your own suggestions.<P>
	310
	311	<H3><a name="newport">How do I start a new port?</a></H3>
	312
	313	Please subscribe to the wx-dev <a href="maillst2.htm">developers' mailing list</a> and
	314	ask if anyone else is interested in helping with the port, or
	315	has specific suggestions. Also please read the <a href="standard.htm">coding standards</a>.
	316
	317	<P>
	318	Each port consists of a platform-specific part (e.g. src/msw, include/wx/msw),
	319	a generic set of widgets and dialogs for when the port doesn't support
	320	them natively (src/generic, include/wx/generic) and the common code
	321	that all ports use (src/common, include/wx). By browsing the source
	322	you should get a good idea of the general pattern.<P>
	323
	324	Take a port that most closely matches your port, and strip out
	325	the implementation so you have a skeleton port that compiles. Ask on wx-dev
	326	first for the wxStubs port - however, any such predefined skeleton
	327	port may be out of date, so make a judgement on whether to use it.
	328	Perhaps it will still save you time to clean up wxStubs, and
	329	others may benefit from this too.<P>
	330
	331	You will need to define a symbol for the new port, e.g. __WXXBOX__.
	332	Look at files such as wx/defs.h, wx/wxchar.h for areas where you'll
	333	need to add to existing conditionals to set up wide character
	334	support and other issues. If the GUI runs on a Unix variant,
	335	define the __UNIX__ variable in your makefile.<P>
	336
	337	Then you can start implementing the port, starting with
	338	wxWindow, wxTopLevelWindow, wxFrame, wxDialog so you
	339	can get the minimal sample running as soon as possible.<P>
	340
	341	If GDI objects (wxPen, wxBrush, etc.) are not concepts in your
	342	native GUI, you may wish to use very generic versions of
	343	some of these - see the wxX11 port.<P>
	344
	345	Consider using the wxUniversal widget set as a quick way
	346	to implement wxWidgets on your platform. You only need
	347	to define some basic classes such as device contexts,
	348	wxWindow, wxTopLevelWindow, GDI objects etc. and
	349	the actual widgets will be drawn for you. See wxX11,
	350	wxMGL, and wxMSW/Univ for sample wxUniversal ports.<P>
	351
	352	To begin with, you can use whatever makefiles or project
	353	files work for you. Look at existing makefiles to see what
	354	generic/common/Unix files need to be included. Later, you'll want to integrate support
	355	for your port into configure (Unix-like systems and gcc under Windows),
	356	and bakefile (for other makefiles on Windows).<P>
	357
	358	Submit your port as patches via SourceForge; you might
	359	wish to separate it into one patch that touches common headers
	360	and source files, and another containing the port-specific code, to make
	361	it much easier for us to review and apply the patches.<P>
	362
	363	Good luck!
	364
	365	</font>
	366
	367	</BODY>
	368
	369	</HTML>