// Name: devtips.h
// Purpose: Cross-platform development page of the Doxygen manual
// Author: wxWidgets team
-// RCS-ID: $Id$
-// Licence: wxWindows license
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-
/**
- @page page_multiplatform Multi-platform development with wxWidgets
+@page page_multiplatform General Cross-Platform Development Tips
+
+@tableofcontents
+
+This chapter describes some tips related to cross-platform development.
+
+
+
+@section page_multiplatform_includefiles Include Files
+
+The main include file is @c "wx/wx.h"; this includes the most commonly used
+modules of wxWidgets.
+
+To save on compilation time, include only those header files relevant to the
+source file. If you are using @b precompiled headers, you should include the
+following section before any other includes:
+
+@verbatim
+// For compilers that support precompilation, includes "wx.h".
+#include <wx/wxprec.h>
+
+#ifdef __BORLANDC__
+# pragma hdrstop
+#endif
+
+#ifndef WX_PRECOMP
+ // Include your minimal set of headers here, or wx.h
+# include <wx/wx.h>
+#endif
+
+... now your other include files ...
+@endverbatim
+
+The file @c "wx/wxprec.h" includes @c "wx/wx.h". Although this incantation may
+seem quirky, it is in fact the end result of a lot of experimentation, and
+several Windows compilers to use precompilation which is largely automatic for
+compilers with necessary support. Currently it is used for Visual C++
+(including embedded Visual C++), Borland C++, Open Watcom C++, Digital Mars C++
+and newer versions of GCC. Some compilers might need extra work from the
+application developer to set the build environment up as necessary for the
+support.
+
+
+
+@section page_multiplatform_libraries Libraries
+
+All ports of wxWidgets can create either a @b static library or a @b shared
+library.
+
+When a program is linked against a @e static library, the machine code from the
+object files for any external functions used by the program is copied from the
+library into the final executable.
+
+@e Shared libraries are handled with a more advanced form of linking, which
+makes the executable file smaller. They use the extension @c ".so" (Shared
+Object) under Linux and @c ".dll" (Dynamic Link Library) under Windows.
+
+An executable file linked against a shared library contains only a small table
+of the functions it requires, instead of the complete machine code from the
+object files for the external functions. Before the executable file starts
+running, the machine code for the external functions is copied into memory from
+the shared library file on disk by the operating system - a process referred to
+as @e dynamic linking.
- This chapter describes the practical details of using wxWidgets. Please
- see the file install.txt for up-to-date installation instructions, and
- changes.txt for differences between versions.
+Dynamic linking makes executable files smaller and saves disk space, because
+one copy of a library can be shared between multiple programs. Most operating
+systems also provide a virtual memory mechanism which allows one copy of a
+shared library in physical memory to be used by all running programs, saving
+memory as well as disk space.
- @li @ref page_multiplatform_includefiles
- @li @ref page_multiplatform_libraries
- @li @ref page_multiplatform_configuration
- @li @ref page_multiplatform_makefiles
- @li @ref page_multiplatform_windowsfiles
- @li @ref page_multiplatform_allocatingobjects
- @li @ref page_multiplatform_architecturedependency
- @li @ref page_multiplatform_conditionalcompilation
- @li @ref page_multiplatform_cpp
- @li @ref page_multiplatform_filehandling
+Furthermore, shared libraries make it possible to update a library without
+recompiling the programs which use it (provided the interface to the library
+does not change).
- <hr>
+wxWidgets can also be built in @b multilib and @b monolithic variants. See the
+@ref page_libs for more information on these.
- @section page_multiplatform_includefiles Include files
- The main include file is @c "wx/wx.h"; this includes the most commonly
- used modules of wxWidgets.
+@section page_multiplatform_configuration Configuration
- To save on compilation time, include only those header files relevant to the
- source file. If you are using precompiled headers, you should include
- the following section before any other includes:
+When using project files and makefiles directly to build wxWidgets, options are
+configurable in the file @c "wx/XXX/setup.h" where XXX is the required
+platform (such as @c msw, @c motif, @c gtk, @c mac).
- @verbatim
- // For compilers that support precompilation, includes "wx.h".
- #include <wx/wxprec.h>
+Some settings are a matter of taste, some help with platform-specific problems,
+and others can be set to minimize the size of the library. Please see the
+@c "setup.h" file and @c "install.txt" files for details on configuration.
- #ifdef __BORLANDC__
- #pragma hdrstop
- #endif
+When using the @c "configure" script to configure wxWidgets (on Unix and other
+platforms where configure is available), the corresponding @c "setup.h" files
+are generated automatically along with suitable makefiles.
- #ifndef WX_PRECOMP
- // Include your minimal set of headers here, or wx.h
- #include <wx/wx.h>
- #endif
+When using the RPM packages (or DEB or other forms of @e binaries) for
+installing wxWidgets on Linux, a correct @c "setup.h" is shipped in the package
+and this must not be changed.
- ... now your other include files ...
- @endverbatim
- The file @c "wx/wxprec.h" includes @c "wx/wx.h". Although this incantation
- may seem quirky, it is in fact the end result of a lot of experimentation,
- and several Windows compilers to use precompilation which is largely automatic for
- compilers with necessary support. Currently it is used for Visual C++ (including
- embedded Visual C++), Borland C++, Open Watcom C++, Digital Mars C++
- and newer versions of GCC.
- Some compilers might need extra work from the application developer to set the
- build environment up as necessary for the support.
+@section page_multiplatform_makefiles Makefiles
+On Microsoft Windows, wxWidgets has a different set of makefiles for each
+compiler, because each compiler's @c 'make' tool is slightly different. Popular
+Windows compilers that we cater for, and the corresponding makefile extensions,
+include: Microsoft Visual C++ (.vc), Borland C++ (.bcc), OpenWatcom C++ (.wat)
+and MinGW/Cygwin (.gcc). Makefiles are provided for the wxWidgets library
+itself, samples, demos, and utilities.
- @section page_multiplatform_libraries Libraries
+On Linux, Mac and OS/2, you use the @c 'configure' command to generate the
+necessary makefiles. You should also use this method when building with
+MinGW/Cygwin on Windows.
- Most ports of wxWidgets can create either a static library or a shared
- library. wxWidgets can also be built in multilib and monolithic variants.
- See the @ref page_libs for more information on these.
+We also provide project files for some compilers, such as Microsoft VC++.
+However, we recommend using makefiles to build the wxWidgets library itself,
+because makefiles can be more powerful and less manual intervention is
+required.
+On Windows using a compiler other than MinGW/Cygwin, you would build the
+wxWidgets library from the @c "build/msw" directory which contains the relevant
+makefiles.
+On Windows using MinGW/Cygwin, and on Unix, MacOS X and OS/2, you invoke
+'configure' (found in the top-level of the wxWidgets source hierarchy), from
+within a suitable empty directory for containing makefiles, object files and
+libraries.
- @section page_multiplatform_configuration Configuration
+For details on using makefiles, configure, and project files, please see
+@c "docs/xxx/install.txt" in your distribution, where @c "xxx" is the platform
+of interest, such as @c msw, @c gtk, @c x11, @c mac.
- When using project files and makefiles directly to build wxWidgets,
- options are configurable in the file
- @c "wx/XXX/setup.h" where XXX is the required platform (such as msw, motif, gtk, mac). Some
- settings are a matter of taste, some help with platform-specific problems, and
- others can be set to minimize the size of the library. Please see the setup.h file
- and @c install.txt files for details on configuration.
+All wxWidgets makefiles are generated using Bakefile <http://www.bakefile.org/>.
+wxWidgets also provides (in the @c "build/bakefiles/wxpresets" folder) the
+wxWidgets bakefile presets. These files allow you to create bakefiles for your
+own wxWidgets-based applications very easily.
- When using the 'configure' script to configure wxWidgets (on Unix and other platforms where
- configure is available), the corresponding setup.h files are generated automatically
- along with suitable makefiles. When using the RPM packages
- for installing wxWidgets on Linux, a correct setup.h is shipped in the package and
- this must not be changed.
+@section page_multiplatform_winresources Windows Resource Files
- @section page_multiplatform_makefiles Makefiles
+wxWidgets application compilation under MS Windows requires at least one extra
+file: a resource file.
- On Microsoft Windows, wxWidgets has a different set of makefiles for each
- compiler, because each compiler's 'make' tool is slightly different.
- Popular Windows compilers that we cater for, and the corresponding makefile
- extensions, include: Microsoft Visual C++ (.vc), Borland C++ (.bcc),
- OpenWatcom C++ (.wat) and MinGW/Cygwin (.gcc). Makefiles are provided
- for the wxWidgets library itself, samples, demos, and utilities.
+The least that must be defined in the Windows resource file (extension RC) is
+the following statement:
- On Linux, Mac and OS/2, you use the 'configure' command to
- generate the necessary makefiles. You should also use this method when
- building with MinGW/Cygwin on Windows.
+@verbatim
+#include "wx/msw/wx.rc"
+@endverbatim
- We also provide project files for some compilers, such as
- Microsoft VC++. However, we recommend using makefiles
- to build the wxWidgets library itself, because makefiles
- can be more powerful and less manual intervention is required.
+which includes essential internal wxWidgets definitions. The resource script
+may also contain references to icons, cursors, etc., for example:
- On Windows using a compiler other than MinGW/Cygwin, you would
- build the wxWidgets library from the build/msw directory
- which contains the relevant makefiles.
+@verbatim
+wxicon icon wx.ico
+@endverbatim
- On Windows using MinGW/Cygwin, and on Unix, MacOS X and OS/2, you invoke
- 'configure' (found in the top-level of the wxWidgets source hierarchy),
- from within a suitable empty directory for containing makefiles, object files and
- libraries.
+The icon can then be referenced by name when creating a frame icon. See the
+Microsoft Windows SDK documentation.
- For details on using makefiles, configure, and project files,
- please see docs/xxx/install.txt in your distribution, where
- xxx is the platform of interest, such as msw, gtk, x11, mac.
+@note Include "wx.rc" @e after any ICON statements so programs that search your
+ executable for icons (such as the Program Manager) find your application
+ icon first.
- @section page_multiplatform_windowsfiles Windows-specific files
+@section page_multiplatform_allocatingobjects Allocating and Deleting wxWidgets Objects
- wxWidgets application compilation under MS Windows requires at least one
- extra file: a resource file.
+In general, classes derived from wxWindow must dynamically allocated with
+@e new and deleted with @e delete. If you delete a window, all of its children
+and descendants will be automatically deleted, so you don't need to delete
+these descendants explicitly.
- @subsection page_multiplatform_windowsfiles_resources Resource file
+When deleting a frame or dialog, use @b Destroy rather than @b delete so that
+the wxWidgets delayed deletion can take effect. This waits until idle time
+(when all messages have been processed) to actually delete the window, to avoid
+problems associated with the GUI sending events to deleted windows.
- The least that must be defined in the Windows resource file (extension RC)
- is the following statement:
+In general wxWindow-derived objects should always be allocated on the heap
+as wxWidgets will destroy them itself. The only, but important, exception to
+this rule are the modal dialogs, i.e. wxDialog objects which are shown using
+wxDialog::ShowModal() method. They may be allocated on the stack and, indeed,
+usually are local variables to ensure that they are destroyed on scope exit as
+wxWidgets does not destroy them unlike with all the other windows. So while it
+is still possible to allocate modal dialogs on the heap, you should still
+destroy or delete them explicitly in this case instead of relying on wxWidgets
+doing it.
- @verbatim
- #include "wx/msw/wx.rc"
- @endverbatim
+If you decide to allocate a C++ array of objects (such as wxBitmap) that may be
+cleaned up by wxWidgets, make sure you delete the array explicitly before
+wxWidgets has a chance to do so on exit, since calling @e delete on array
+members will cause memory problems.
- which includes essential internal wxWidgets definitions. The resource script
- may also contain references to icons, cursors, etc., for example:
+wxColour can be created statically: it is not automatically cleaned
+up and is unlikely to be shared between other objects; it is lightweight
+enough for copies to be made.
- @verbatim
- wxicon icon wx.ico
- @endverbatim
+Beware of deleting objects such as a wxPen or wxBitmap if they are still in
+use. Windows is particularly sensitive to this, so make sure you make calls
+like wxDC::SetPen(wxNullPen) or wxDC::SelectObject(wxNullBitmap) before
+deleting a drawing object that may be in use. Code that doesn't do this will
+probably work fine on some platforms, and then fail under Windows.
- The icon can then be referenced by name when creating a frame icon. See
- the MS Windows SDK documentation.
- @note include wx.rc @e after any ICON statements
- so programs that search your executable for icons (such
- as the Program Manager) find your application icon first.
+@section page_multiplatform_architecturedependency Architecture Dependency
+A problem which sometimes arises from writing multi-platform programs is that
+the basic C types are not defined the same on all platforms. This holds true
+for both the length in bits of the standard types (such as int and long) as
+well as their byte order, which might be little endian (typically on Intel
+computers) or big endian (typically on some Unix workstations). wxWidgets
+defines types and macros that make it easy to write architecture independent
+code. The types are:
- @section page_multiplatform_allocatingobjects Allocating and deleting wxWidgets objects
+wxInt32, wxInt16, wxInt8, wxUint32, wxUint16 = wxWord, wxUint8 = wxByte
- In general, classes derived from wxWindow must dynamically allocated
- with @e new and deleted with @e delete. If you delete a window,
- all of its children and descendants will be automatically deleted,
- so you don't need to delete these descendants explicitly.
+where wxInt32 stands for a 32-bit signed integer type etc. You can also check
+which architecture the program is compiled on using the wxBYTE_ORDER define
+which is either wxBIG_ENDIAN or wxLITTLE_ENDIAN (in the future maybe
+wxPDP_ENDIAN as well).
- When deleting a frame or dialog, use @b Destroy rather than @b delete so
- that the wxWidgets delayed deletion can take effect. This waits until idle time
- (when all messages have been processed) to actually delete the window, to avoid
- problems associated with the GUI sending events to deleted windows.
+The macros handling bit-swapping with respect to the applications endianness
+are described in the @ref group_funcmacro_byteorder section.
- Don't create a window on the stack, because this will interfere
- with delayed deletion.
- If you decide to allocate a C++ array of objects (such as wxBitmap) that may
- be cleaned up by wxWidgets, make sure you delete the array explicitly
- before wxWidgets has a chance to do so on exit, since calling @e delete on
- array members will cause memory problems.
- wxColour can be created statically: it is not automatically cleaned
- up and is unlikely to be shared between other objects; it is lightweight
- enough for copies to be made.
+@section page_multiplatform_conditionalcompilation Conditional Compilation
- Beware of deleting objects such as a wxPen or wxBitmap if they are still in use.
- Windows is particularly sensitive to this: so make sure you
- make calls like wxDC::SetPen(wxNullPen) or wxDC::SelectObject(wxNullBitmap) before deleting
- a drawing object that may be in use. Code that doesn't do this will probably work
- fine on some platforms, and then fail under Windows.
+One of the purposes of wxWidgets is to reduce the need for conditional
+compilation in source code, which can be messy and confusing to follow.
+However, sometimes it is necessary to incorporate platform-specific features
+(such as metafile use under MS Windows). The @ref page_wxusedef symbols listed
+in the file @c setup.h may be used for this purpose, along with any
+user-supplied ones.
- @section page_multiplatform_architecturedependency Architecture dependency
+@section page_multiplatform_cpp C++ Issues
- A problem which sometimes arises from writing multi-platform programs is that
- the basic C types are not defined the same on all platforms. This holds true
- for both the length in bits of the standard types (such as int and long) as
- well as their byte order, which might be little endian (typically
- on Intel computers) or big endian (typically on some Unix workstations). wxWidgets
- defines types and macros that make it easy to write architecture independent
- code. The types are:
+The following documents some miscellaneous C++ issues.
- wxInt32, wxInt16, wxInt8, wxUint32, wxUint16 = wxWord, wxUint8 = wxByte
+@subsection page_multiplatform_cpp_templates Templates
- where wxInt32 stands for a 32-bit signed integer type etc. You can also check
- which architecture the program is compiled on using the wxBYTE_ORDER define
- which is either wxBIG_ENDIAN or wxLITTLE_ENDIAN (in the future maybe wxPDP_ENDIAN
- as well).
+wxWidgets does not use templates (except for some advanced features that are
+switched off by default) since it is a notoriously unportable feature.
- The macros handling bit-swapping with respect to the applications endianness
- are described in the @ref page_macro_cat_byteorder section.
+@subsection page_multiplatform_cpp_rtti Runtime Type Information (RTTI)
+wxWidgets does not use C++ run-time type information since wxWidgets provides
+its own run-time type information system, implemented using macros.
+@subsection page_multiplatform_cpp_precompiledheaders Precompiled Headers
- @section page_multiplatform_conditionalcompilation Conditional compilation
+Some compilers, such as Borland C++ and Microsoft C++, support precompiled
+headers. This can save a great deal of compiling time. The recommended approach
+is to precompile @c "wx.h", using this precompiled header for compiling both
+wxWidgets itself and any wxWidgets applications. For Windows compilers, two
+dummy source files are provided (one for normal applications and one for
+creating DLLs) to allow initial creation of the precompiled header.
- One of the purposes of wxWidgets is to reduce the need for conditional
- compilation in source code, which can be messy and confusing to follow.
- However, sometimes it is necessary to incorporate platform-specific
- features (such as metafile use under MS Windows). The @ref page_wxusedef
- symbols listed in the file @c setup.h may be used for this purpose,
- along with any user-supplied ones.
+However, there are several downsides to using precompiled headers. One is that
+to take advantage of the facility, you often need to include more header files
+than would normally be the case. This means that changing a header file will
+cause more recompilations (in the case of wxWidgets, everything needs to be
+recompiled since everything includes @c "wx.h").
+A related problem is that for compilers that don't have precompiled headers,
+including a lot of header files slows down compilation considerably. For this
+reason, you will find (in the common X and Windows parts of the library)
+conditional compilation that under Unix, includes a minimal set of headers; and
+when using Visual C++, includes @c "wx.h". This should help provide the optimal
+compilation for each compiler, although it is biased towards the precompiled
+headers facility available in Microsoft C++.
- @section page_multiplatform_cpp C++ issues
- The following documents some miscellaneous C++ issues.
+@section page_multiplatform_filehandling File Handling
- @subsection page_multiplatform_cpp_templates Templates
+When building an application which may be used under different environments,
+one difficulty is coping with documents which may be moved to different
+directories on other machines. Saving a file which has pointers to full
+pathnames is going to be inherently unportable.
- wxWidgets does not use templates (except for some advanced features that
- are switched off by default) since it is a notoriously unportable feature.
+One approach is to store filenames on their own, with no directory information.
+The application then searches into a list of standard paths (platform-specific)
+through the use of wxStandardPaths.
- @subsection page_multiplatform_cpp_rtti RTTI
+Eventually you may want to use also the wxPathList class.
- wxWidgets does not use C++ run-time type information since wxWidgets provides
- its own run-time type information system, implemented using macros.
+Nowadays the limitations of DOS 8+3 filenames doesn't apply anymore. Most
+modern operating systems allow at least 255 characters in the filename; the
+exact maximum length, as well as the characters allowed in the filenames, are
+OS-specific so you should try to avoid extremely long (> 255 chars) filenames
+and/or filenames with non-ANSI characters.
- @subsection page_multiplatform_cpp_null Type of NULL
+Another thing you need to keep in mind is that all Windows operating systems
+are case-insensitive, while Unix operating systems (Linux, Mac, etc) are
+case-sensitive.
- Some compilers (e.g. the native IRIX cc) define NULL to be 0L so that
- no conversion to pointers is allowed. Because of that, all these
- occurrences of NULL in the GTK+ port use an explicit conversion such
- as
+Also, for text files, different OSes use different End Of Lines (EOL). Windows
+uses CR+LF convention, Linux uses LF only, Mac CR only.
- @code
- wxWindow *my_window = (wxWindow*) NULL;
- @endcode
+The wxTextFile, wxTextInputStream, wxTextOutputStream classes help to abstract
+from these differences. Of course, there are also 3rd party utilities such as
+@c dos2unix and @c unix2dos which do the EOL conversions.
- It is recommended to adhere to this in all code using wxWidgets as
- this make the code (a bit) more portable.
+See also the @ref group_funcmacro_file section of the reference manual for the
+description of miscellaneous file handling functions.
- @subsection page_multiplatform_cpp_precompiledheaders Precompiled headers
- Some compilers, such as Borland C++ and Microsoft C++, support
- precompiled headers. This can save a great deal of compiling time. The
- recommended approach is to precompile @c "wx.h", using this
- precompiled header for compiling both wxWidgets itself and any
- wxWidgets applications. For Windows compilers, two dummy source files
- are provided (one for normal applications and one for creating DLLs)
- to allow initial creation of the precompiled header.
- However, there are several downsides to using precompiled headers. One
- is that to take advantage of the facility, you often need to include
- more header files than would normally be the case. This means that
- changing a header file will cause more recompilations (in the case of
- wxWidgets, everything needs to be recompiled since everything includes @c "wx.h" !)
+@section page_multiplatform_reducingerr Reducing Programming Errors
- A related problem is that for compilers that don't have precompiled
- headers, including a lot of header files slows down compilation
- considerably. For this reason, you will find (in the common
- X and Windows parts of the library) conditional
- compilation that under Unix, includes a minimal set of headers;
- and when using Visual C++, includes @c wx.h. This should help provide
- the optimal compilation for each compiler, although it is
- biased towards the precompiled headers facility available
- in Microsoft C++.
+@subsection page_multiplatform_reducingerr_useassert Use ASSERT
+It is good practice to use ASSERT statements liberally, that check for
+conditions that should or should not hold, and print out appropriate error
+messages.
+These can be compiled out of a non-debugging version of wxWidgets and your
+application. Using ASSERT is an example of `defensive programming': it can
+alert you to problems later on.
- @section page_multiplatform_filehandling File handling
+See wxASSERT() for more info.
- When building an application which may be used under different
- environments, one difficulty is coping with documents which may be
- moved to different directories on other machines. Saving a file which
- has pointers to full pathnames is going to be inherently unportable.
+@subsection page_multiplatform_reducingerr_usewxstring Use wxString in Preference to Character Arrays
- One approach is to store filenames on their own, with no directory
- information. The application then searches into a list of standard
- paths (platform-specific) through the use of wxStandardPaths.
+Using wxString can be much safer and more convenient than using @c wxChar*.
- Eventually you may want to use also the wxPathList class.
+You can reduce the possibility of memory leaks substantially, and it is much
+more convenient to use the overloaded operators than functions such as
+@c strcmp. wxString won't add a significant overhead to your program; the
+overhead is compensated for by easier manipulation (which means less code).
- Nowadays the limitations of DOS 8+3 filenames doesn't apply anymore.
- Most modern operating systems allow at least 255 characters in the filename;
- the exact maximum length, as well as the characters allowed in the filenames,
- are OS-specific so you should try to avoid extremely long (> 255 chars) filenames
- and/or filenames with non-ANSI characters.
+The same goes for other data types: use classes wherever possible.
- Another thing you need to keep in mind is that all Windows operating systems
- are case-insensitive, while Unix operating systems (Linux, Mac, etc) are
- case-sensitive.
- Also, for text files, different OSes use different End Of Lines (EOL).
- Windows uses CR+LF convention, Linux uses LF only, Mac CR only.
- The wxTextFile, wxTextInputStream, wxTextOutputStream classes help to abstract
- from these differences.
- Of course, there are also 3rd party utilities such as @c dos2unix and @c unix2dos
- which do the EOL conversions.
+@section page_multiplatform_gui GUI Design
- See also the @ref page_func_cat_file section of the reference
- manual for the description of miscellaneous file handling functions.
+@li <b>Use Sizers:</b> Don't use absolute panel item positioning if you can
+ avoid it. Every platform's native controls have very different sizes.
+ Consider using the @ref overview_sizer instead.
+@li <b>Use wxWidgets Resource Files:</b> Use @c XRC (wxWidgets resource files)
+ where possible, because they can be easily changed independently of source
+ code. See the @ref overview_xrc for more info.
+
+
+
+@section page_multiplatform_debug Debugging
+
+@subsection page_multiplatform_debug_positivethinking Positive Thinking
+
+It is common to blow up the problem in one's imagination, so that it seems to
+threaten weeks, months or even years of work. The problem you face may seem
+insurmountable: but almost never is. Once you have been programming for some
+time, you will be able to remember similar incidents that threw you into the
+depths of despair. But remember, you always solved the problem, somehow!
+
+Perseverance is often the key, even though a seemingly trivial problem can take
+an apparently inordinate amount of time to solve. In the end, you will probably
+wonder why you worried so much. That's not to say it isn't painful at the time.
+Try not to worry -- there are many more important things in life.
+
+@subsection page_multiplatform_debug_simplifyproblem Simplify the Problem
+
+Reduce the code exhibiting the problem to the smallest program possible that
+exhibits the problem. If it is not possible to reduce a large and complex
+program to a very small program, then try to ensure your code doesn't hide the
+problem (you may have attempted to minimize the problem in some way: but now
+you want to expose it).
+
+With luck, you can add a small amount of code that causes the program to go
+from functioning to non-functioning state. This should give a clue to the
+problem. In some cases though, such as memory leaks or wrong deallocation, this
+can still give totally spurious results!
+
+@subsection page_multiplatform_debug_usedebugger Use a Debugger
+
+This sounds like facetious advice, but it is surprising how often people don't
+use a debugger. Often it is an overhead to install or learn how to use a
+debugger, but it really is essential for anything but the most trivial
+programs.
+
+@subsection page_multiplatform_debug_uselogging Use Logging Functions
+
+There is a variety of logging functions that you can use in your program: see
+@ref group_funcmacro_log.
+
+Using tracing statements may be more convenient than using the debugger in some
+circumstances (such as when your debugger doesn't support a lot of debugging
+code, or you wish to print a bunch of variables).
+
+@subsection page_multiplatform_debug_usedebuggingfacilities Use the wxWidgets Debugging Facilities
+
+You can use wxDebugContext to check for memory leaks and corrupt memory: in
+fact in debugging mode, wxWidgets will automatically check for memory leaks at
+the end of the program if wxWidgets is suitably configured. Depending on the
+operating system and compiler, more or less specific information about the
+problem will be logged.
+
+You should also use @ref group_funcmacro_debug as part of a "defensive
+programming" strategy, scattering wxASSERT()s liberally to test for problems in
+your code as early as possible. Forward thinking will save a surprising amount
+of time in the long run.
+
+See the @ref overview_debugging for further information.
*/
+
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