wxWidgets/docs/html/faqgen.htm
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wxWindows 2 FAQ: General
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<P>
See also <a href="faq.htm">top-level FAQ page</a>.
<hr>
<H3><a name="whatis">What is wxWindows?</a></H3>
wxWindows is a class library that allows you to compile graphical C++ programs on a range of
different platforms. wxWindows defines a common API across platforms, but uses the native graphical user interface (GUI) on each platform,
so your program will take on the native 'look and feel' that users are familiar with.<P>
Although GUI applications are mostly built programmatically, there is a dialog editor to help
build attractive dialogs and panels.<P>
You don't have to use C++ to use wxWindows: wxWindows 1 has been interfaced to several interpreted languages,
such as CLIPS, Python, Scheme, XLisp and Perl, and there is a Python interface for wxWindows 2.
<P>
<h3>Can I use wxWindows 2 for both proprietary (commercial) projects, and GPL'ed projects?</h3>
Yes. Please see the <a href="newlicen.htm">licence</a> for details, but basically
you can distribute proprietary binaries without distributing any source code, and neither will wxWindows
conflict with GPL code you may be using or developing with it.
<P>
The conditions for using wxWindows 2 are the same whether you are a personal, academic
or commercial developer.
<P>
<h3>Is there support?</h3>
No official support, but the mailing list is very helpful and some people say that
wxWindows support is better than for much commercial software. The developers are
keen to fix bugs as soon as possible, though obviously there are no guarantees.
<P>
<H3><a name="users">Who uses wxWindows?</a></H3>
Many organisations - commercial, government, and academic - across the
world. It's impossible to estimate the true number of users, since
wxWindows is obtained by many different means, and we cannot monitor
distribution. The mailing list contains around 300-400 entries which is
quite large for a list of this type.<P>
<H3>I am about to start a wxWindows 1.xx project. Should I use 2 instead?</H3>
wxWindows 2 is still in beta but it's actually pretty useable (Windows, GTK, Motif).<P>
Porting to wxWindows 2 from 1.xx will not be too painful; see the next question
for ways in which you can make it easier.<P>
<H3>Why would I want to use wxWindows 2 in preference to wxWindows 1.xx?</H3>
Some reasons:
<ul>
<li>In 2 there is far more flexibility, for example in the way windows can be
nested, and the way events are intercepted.
<li>There is more functionality for producing sophisticated applications,
for example using the wxTreeCtrl and wxListCtrl classes.
<li>There is better C++-conformance (such as usage of wxString and const) which
will make your applications more reliable and easier to maintain.
<li>wxWindows 2 will be better supported than 1.xx.
<li>The GTK version is attractive for people interested in writing Linux and GNOME
applications.
<li>The Mac version will be one of the best frameworks available on that platform.
</ul>
<H3>How can I prepare for wxWindows 2?</H3>
To make porting to wxWindows 2 easier in the future, take a look at some
<a href="http://www.wxwindows.org/prepare.htm">tips</a> for writing existing code in a 2-compatible way.<P>
<H3>How much has the API changed since 1.xx?</H3>
It's difficult to summarize, but some aspects haven't changed very much. For example, if you have some
complex drawing code, you will mostly need to make sure it's parameterised with a device
context (instead of obtaining one from a window or storing it). You won't have
to completely rewrite the drawing code.<P>
The way that events are handled has changed, so for example, where you overrode
OnSize before, you now have a non-virtual OnSize with a single event class argument.
To make this function known to wxWindows, you add an entry in an 'event table' using macros. Addition of these macros
will eventually be made easier by a tool which will allow selection from a list
and copy-and-paste into your editor. This is extended to button presses, listbox selection
etc. so callbacks have gone (they may be added back for limited backward compatibility).<P>
The class hierarchy has changed to allow greater flexibility but it probably won't affect your
existing application. One exception to this is MDI applications which now use separate MDI classes instead of style
flags. As a result, it won't be possible to switch between MDI and SDI operation at run-time
without further coding, but a benefit is less interdependence between areas of code,
and therefore smaller executable size.<P>
Panel items (now called controls) no longer have labels associated with most of them,
and default panel layout has been removed. The idea is that you make greater use
of dialog resources, for better-looking dialogs.<P>
<H3>What classes have disappeared?</H3>
wxForm, wxTextWindow (subsumed into wxTextCtrl).
<H3>Does wxWindows 2 mean that wxWindows 1.xx is dead?</H3>
While wxWindows 2 is being developed, there will be further patches to wxWindows 1.xx.
Obviously we are investing most of our energy into the new code, but we're also trying
to fix bugs in the current version.<P>
<H3>What platforms will be supported by wxWindows 2?</H3>
<ul>
<li>Windows 3.1, Windows 95/98, Windows NT;
<li>Linux and other Unix platforms with GTK+;
<li>Unix with Motif or the free Motif clone Lesstif;
<li>Mac (coming later in 1999);
<li>A BeOS port is being investigated.
<li>A Windows CE port is being investigated.
<li>There are no plans to support OS/2 or XView. However,
you may be able to compile the GTK and Motif versions under OS/2 with X and GTK
installed, or the Windows version with IBM's Open32 extensions.
</ul>
<P>
<H3>How does wxWindows 2 support platform-specific features?</H3>
This is a hotly-debated topic amongst the developers. My own philosophy
is to make wxWindows as platform-independent as possible, but allow in a
few classes (functions, window styles) that are platform-specific.
For example, Windows metafiles and Windows 95 taskbar icons have
their own classes on Windows, but nowhere else. Because these classes
are provided and are wxWindows-compatible, it doesn't take much
coding effort for an application programmer to add support for
some functionality that the user on a particular platform might otherwise
miss. Also, some classes that started off as platform-specific, such
as the MDI classes, have been emulated on other platforms. I can imagine
that even wxTaskBarIcon may be implemented for Unix desktops one day.
<P>
In other words, wxWindows is not a 'lowest common denominator' approach,
but it will still be possible to write portable programs using the
core API. Forbidding some platform-specific classes would be a stupid
approach that would alienate many potential users, and encourage
the perception that toolkits such as wxWindows are not up to the demands
of today's sophisticated applications.<P>
Currently resources such as bitmaps and icons are handled in a platform-specific
way, but it is hoped to reduce this dependence in due course.<P>
Another reason why wxWindows 2 is not a 'lowest common denominator' toolkit is that
some functionality missing on some platform has been provided using generic,
platform-independent code, such as the wxTreeCtrl and wxListCtrl classes.<P>
<H3>Does wxWindows use STL? or the standard string class?</H3>
No. This is a much-discussed topic that has (many times) ended with the conclusion that it is in
wxWindows' best interests to avoid use of templates. Not all compilers can handle
templates adequately so it would dramatically reduce the number of compilers
and platforms that could be supported. It would also be undersirable to make
wxWindows dependent on another large library that may have to be downloaded and installed.
In addition, use of templates can lead to executable bloat, which is something
wxWindows 2 is strenously trying to avoid.<P>
The standard C++ string class is not used, again because it is not available to all compilers,
and it is not necessarily a very efficient implementation. Also, we retain more flexibility
by being able to modify our own string class. Some compatibility with the string class
has been built into wxString.<P>
There is nothing to stop an application using templates or the string class for its own
purposes.<P>
<H3>How is wxWindows 2 being developed?</H3>
We are using the <a href="cvs.htm">CVS</a> system to develop and maintain wxWindows. This allows
us to make alterations and upload them instantly to the server in Edinburgh, from
which others can update their source.<P>
To build source from CVS, see the file BuildCVS.txt in the top-level wxWindows distribution
directory.<P>
<H3>How is wxWindows 2 distributed?</H3>
By ftp, and via the <a href="cdrom2.htm">wxWindows CD-ROM</a>.<P>
<H3>What are the plans for the future?</H3>
Currently we're working too hard on getting wxWindows 2 finished (are GUI toolkits ever
finished?) to think very far ahead. However, we know we want to make wxWindows as robust
and well-publicised as possible. We also want to aim for better platform-independence of
resources such as icons and bitmaps, standardising on the PNG for all platforms.<P>
Other possibilities include: DCOM/CORBA compatibility; a wxWindows book;
<a href="http://wxstudio.linuxbox.com/">wxStudio</a>, an IDE;
other platforms; other interface abilities such as speech output.<P>
We will investigate the possibility of compiler or operating system vendors bundling wxWindows with
their product.<P>
The high-level goal of wxWindows is to be thought of as the number one C++ framework,
for virtually any platform. Move over, MFC!<P>
<H3>What about Java?</H3>
The Java honeymoon period is over :-) and people are realising that it cannot
meet all their cross-platform development needs. We don't anticipate a major threat
from Java, and the level of interest in wxWindows is as high as ever.<P>
<H3>How can I help the project?</H3>
Please check out the <a href="http://www.wxwindows.org/develop.htm" target=main>Backroom</a> pages,
in particular the <a href="http://www.wxwindows.org/projects.htm">suggested projects</a>, and
mail <a href="mailto:julian.smart@ukonline.co.uk">Julian Smart</a> or the developers' mailing list with your own suggestions.<P>
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