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1%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2%% Name: log.tex
3%% Purpose: wxLog and related classes documentation
4%% Author: Vadim Zeitlin
5%% Modified by:
6%% Created: some time ago
7%% RCS-ID: $Id$
8%% Copyright: (c) 1997-2001 Vadim Zeitlin
8795498c 9%% License: wxWindows license
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10%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
11
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12\section{\class{wxLog}}\label{wxlog}
13
fc2171bd 14wxLog class defines the interface for the {\it log targets} used by wxWidgets
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15logging functions as explained in the \helpref{wxLog overview}{wxlogoverview}.
16The only situations when you need to directly use this class is when you want
17to derive your own log target because the existing ones don't satisfy your
18needs. Another case is if you wish to customize the behaviour of the standard
19logging classes (all of which respect the wxLog settings): for example, set
20which trace messages are logged and which are not or change (or even remove
21completely) the timestamp on the messages.
22
23Otherwise, it is completely hidden behind the {\it wxLogXXX()} functions and
24you may not even know about its existence.
25
fc2171bd 26See \helpref{log overview}{wxlogoverview} for the descriptions of wxWidgets
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27logging facilities.
28
29\wxheading{Derived from}
30
31No base class
32
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33\wxheading{Include files}
34
35<wx/log.h>
36
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37\latexignore{\rtfignore{\wxheading{Function groups}}}
38
615c6433 39\membersection{Global functions}
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40
41The functions in this section work with and manipulate the active log target.
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42The \helpref{OnLog()}{wxlogonlog} is called by the {\it wxLogXXX()} functions
43and invokes the \helpref{DoLog()}{wxlogdolog} of the active log target if any.
44Get/Set methods are used to install/query the current active target and,
45finally, \helpref{DontCreateOnDemand()}{wxlogdontcreateondemand} disables the
46automatic creation of a standard log target if none actually exists. It is
47only useful when the application is terminating and shouldn't be used in other
48situations because it may easily lead to a loss of messages.
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49
50\helpref{OnLog}{wxlogonlog}\\
51\helpref{GetActiveTarget}{wxloggetactivetarget}\\
42ff6409 52\helpref{SetActiveTarget}{wxlogsetactivetarget}\\
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53\helpref{DontCreateOnDemand}{wxlogdontcreateondemand}\\
54\helpref{Suspend}{wxlogsuspend}\\
55\helpref{Resume}{wxlogresume}
9ee2d31c 56
dcbd177f 57\membersection{Logging functions}\label{loggingfunctions}
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58
59There are two functions which must be implemented by any derived class to
edc73852 60actually process the log messages: \helpref{DoLog}{wxlogdolog} and
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61\helpref{DoLogString}{wxlogdologstring}. The second function receives a string
62which just has to be output in some way and the easiest way to write a new log
63target is to override just this function in the derived class. If more control
64over the output format is needed, then the first function must be overridden
65which allows to construct custom messages depending on the log level or even
66do completely different things depending on the message severity (for example,
67throw away all messages except warnings and errors, show warnings on the
68screen and forward the error messages to the user's (or programmer's) cell
69phone - maybe depending on whether the timestamp tells us if it is day or
70night in the current time zone).
71
72There also functions to support message buffering. Why are they needed?
73Some of wxLog implementations, most notably the standard wxLogGui class,
74buffer the messages (for example, to avoid showing the user a zillion of modal
1ec5cbf3 75message boxes one after another -- which would be really annoying).
4a20e756 76\helpref{Flush()}{wxlogflush} shows them all and clears the buffer contents.
1ec5cbf3 77This function doesn't do anything if the buffer is already empty.
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78
79\helpref{Flush}{wxlogflush}\\
1ec5cbf3 80\helpref{FlushActive}{wxlogflushactive}
9ee2d31c 81
42ff6409 82\membersection{Customization}\label{wxlogcustomization}
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83
84The functions below allow some limited customization of wxLog behaviour
85without writing a new log target class (which, aside of being a matter of
86several minutes, allows you to do anything you want).
87
88The verbose messages are the trace messages which are not disabled in the
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89release mode and are generated by \helpref{wxLogVerbose}{wxlogverbose}. They
90are not normally shown to the user because they present little interest, but
91may be activated, for example, in order to help the user find some program
92problem.
9ee2d31c 93
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94As for the (real) trace messages, their handling depends on the settings of
95the (application global) {\it trace mask}. There are two ways to specify it:
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96either by using \helpref{SetTraceMask}{wxlogsettracemask} and
97\helpref{GetTraceMask}{wxloggettracemask} and using
98\helpref{wxLogTrace}{wxlogtrace} which takes an integer mask or by using
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99\helpref{AddTraceMask}{wxlogaddtracemask} for string trace masks.
100
101The difference between bit-wise and string trace masks is that a message using
102integer trace mask will only be logged if all bits of the mask are set in the
103current mask while a message using string mask will be logged simply if the
104mask had been added before to the list of allowed ones.
105
106For example,
fa482912 107
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108\begin{verbatim}
109// wxTraceOleCalls is one of standard bit masks
110wxLogTrace(wxTraceRefCount | wxTraceOleCalls, "Active object ref count: %d", nRef);
111\end{verbatim}
edc73852 112will do something only if the current trace mask contains both
ac7f0167 113{\tt wxTraceRefCount} and {\tt wxTraceOle}, but
fa482912 114
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115\begin{verbatim}
116// wxTRACE_OleCalls is one of standard string masks
fe482327 117wxLogTrace(wxTRACE_OleCalls, "IFoo::Bar() called");
ac7f0167 118\end{verbatim}
fa482912 119
ac7f0167 120will log the message if it was preceded by
fa482912 121
9ee2d31c 122\begin{verbatim}
ac7f0167 123wxLog::AddTraceMask(wxTRACE_OleCalls);
9ee2d31c 124\end{verbatim}
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125
126Using string masks is simpler and allows to easily add custom ones, so this is
127the preferred way of working with trace messages. The integer trace mask is
128kept for compatibility and for additional (but very rarely needed) flexibility
129only.
130
edc73852 131The standard trace masks are given in \helpref{wxLogTrace}{wxlogtrace}
ac7f0167 132documentation.
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133
134Finally, the {\it wxLog::DoLog()} function automatically prepends a time stamp
135to all the messages. The format of the time stamp may be changed: it can be
2edb0bde 136any string with \% specifications fully described in the documentation of the
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137standard {\it strftime()} function. For example, the default format is
138"[\%d/\%b/\%y \%H:\%M:\%S] " which gives something like "[17/Sep/98 22:10:16] "
139(without quotes) for the current date. Setting an empty string as the time
140format disables timestamping of the messages completely.
141
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142{\bf NB:} Timestamping is disabled for Visual C++ users in debug builds by
143default because otherwise it would be impossible to directly go to the line
144from which the log message was generated by simply clicking in the debugger
edc73852 145window on the corresponding error message. If you wish to enable it, please use
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146\helpref{SetTimestamp}{wxlogsettimestamp} explicitly.
147
148\helpref{AddTraceMask}{wxlogaddtracemask}\\
149\helpref{RemoveTraceMask}{wxlogremovetracemask}\\
36bd6902 150\helpref{ClearTraceMasks}{wxlogcleartracemasks}\\
0e080be6 151\helpref{GetTraceMasks}{wxloggettracemasks}\\
ac7f0167 152\helpref{IsAllowedTraceMask}{wxlogisallowedtracemask}\\
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153\helpref{SetVerbose}{wxlogsetverbose}\\
154\helpref{GetVerbose}{wxloggetverbose}\\
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155\helpref{SetTimestamp}{wxlogsettimestamp}\\
156\helpref{GetTimestamp}{wxloggettimestamp}\\
9ee2d31c 157\helpref{SetTraceMask}{wxlogsettracemask}\\
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158\helpref{GetTraceMask}{wxloggettracemask}\\
159\helpref{SetRepetitionCounting}{wxlogsetrepetitioncounting}\\
160\helpref{GetRepetitionCounting}{wxloggetrepetitioncounting}
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161
162%%%%% MEMBERS HERE %%%%%
163\helponly{\insertatlevel{2}{
164
165\wxheading{Members}
166
167}}
168
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169\membersection{wxLog::AddTraceMask}\label{wxlogaddtracemask}
170
171\func{static void}{AddTraceMask}{\param{const wxString\& }{mask}}
172
edc73852 173Add the {\it mask} to the list of allowed masks for
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174\helpref{wxLogTrace}{wxlogtrace}.
175
0e080be6 176\wxheading{See also}
d2c2afc9 177
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178\helpref{RemoveTraceMask}{wxlogremovetracemask}
179\helpref{GetTraceMasks}{wxloggettracemasks}
ac7f0167 180
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181\membersection{wxLog::ClearTraceMasks}\label{wxlogcleartracemasks}
182
183\func{static void}{ClearTraceMasks}{\void}
184
edc73852 185Removes all trace masks previously set with
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186\helpref{AddTraceMask}{wxlogaddtracemask}.
187
0e080be6 188\wxheading{See also}
d2c2afc9 189
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190\helpref{RemoveTraceMask}{wxlogremovetracemask}
191
192\membersection{wxLog::GetTraceMasks}\label{wxloggettracemasks}
193
bf43ff9a 194\func{static const wxArrayString \&}{GetTraceMasks}{\void}
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195
196Returns the currently allowed list of string trace masks.
197
198\wxheading{See also}
d2c2afc9 199
0e080be6 200\helpref{AddTraceMask}{wxlogaddtracemask}.
36bd6902 201
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202\membersection{wxLog::OnLog}\label{wxlogonlog}
203
5a20d2ce 204\func{static void}{OnLog}{\param{wxLogLevel }{ level}, \param{const wxString\& }{ message}}
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205
206Forwards the message at specified level to the {\it DoLog()} function of the
207active log target if there is any, does nothing otherwise.
208
209\membersection{wxLog::GetActiveTarget}\label{wxloggetactivetarget}
210
211\func{static wxLog *}{GetActiveTarget}{\void}
212
213Returns the pointer to the active log target (may be NULL).
214
215\membersection{wxLog::SetActiveTarget}\label{wxlogsetactivetarget}
216
217\func{static wxLog *}{SetActiveTarget}{\param{wxLog * }{ logtarget}}
218
219Sets the specified log target as the active one. Returns the pointer to the
154b6b0f 220previous active log target (may be NULL). To suppress logging use a new
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221instance of wxLogNull not NULL. If the active log target is set to NULL a
222new default log target will be created when logging occurs.
9ee2d31c 223
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224\membersection{wxLog::Suspend}\label{wxlogsuspend}
225
226\func{static void}{Suspend}{\void}
227
228Suspends the logging until \helpref{Resume}{wxlogresume} is called. Note that
229the latter must be called the same number of times as the former to undo it,
230i.e. if you call Suspend() twice you must call Resume() twice as well.
231
232Note that suspending the logging means that the log sink won't be be flushed
233periodically, it doesn't have any effect if the current log target does the
234logging immediately without waiting for \helpref{Flush}{wxlogflush} to be
235called (the standard GUI log target only shows the log dialog when it is
236flushed, so Suspend() works as expected with it).
237
d2c2afc9 238\wxheading{See also}
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239
240\helpref{Resume}{wxlogresume},\\
241\helpref{wxLogNull}{wxlogoverview}
242
243\membersection{wxLog::Resume}\label{wxlogresume}
244
245\func{static void}{Resume}{\void}
246
edc73852 247Resumes logging previously suspended by a call to
9148009b 248\helpref{Suspend}{wxlogsuspend}. All messages logged in the meanwhile will be
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249flushed soon.
250
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251\membersection{wxLog::DoLog}\label{wxlogdolog}
252
5a20d2ce 253\func{virtual void}{DoLog}{\param{wxLogLevel }{level}, \param{const wxString\& }{msg}, \param{time\_t }{timestamp}}
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254
255Called to process the message of the specified severity. {\it msg} is the text
256of the message as specified in the call of {\it wxLogXXX()} function which
257generated it and {\it timestamp} is the moment when the message was generated.
258
259The base class version prepends the timestamp to the message, adds a prefix
edc73852 260corresponding to the log level and then calls
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261\helpref{DoLogString}{wxlogdologstring} with the resulting string.
262
263\membersection{wxLog::DoLogString}\label{wxlogdologstring}
264
5a20d2ce 265\func{virtual void}{DoLogString}{\param{const wxString\& }{msg}, \param{time\_t }{timestamp}}
4a20e756 266
fab86f26 267Called to log the specified string. The timestamp is already included in the
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268string but still passed to this function.
269
edc73852 270A simple implementation may just send the string to {\tt stdout} or, better,
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271{\tt stderr}.
272
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273\membersection{wxLog::DontCreateOnDemand}\label{wxlogdontcreateondemand}
274
275\func{static void}{DontCreateOnDemand}{\void}
276
277Instructs wxLog to not create new log targets on the fly if there is none
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278currently. (Almost) for internal use only: it is supposed to be called by the
279application shutdown code.
280
edc73852 281Note that this function also calls
36bd6902 282\helpref{ClearTraceMasks}{wxlogcleartracemasks}.
9ee2d31c 283
42ff6409 284\membersection{wxLog::Flush}\label{wxlogflush}
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285
286\func{virtual void}{Flush}{\void}
287
288Shows all the messages currently in buffer and clears it. If the buffer
289is already empty, nothing happens.
290
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291\membersection{wxLog::FlushActive}\label{wxlogflushactive}
292
293\func{static void}{FlushActive}{\void}
294
295Flushes the current log target if any, does nothing if there is none.
296
d2c2afc9 297\wxheading{See also}
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298
299\helpref{Flush}{wxlogflush}
300
42ff6409 301\membersection{wxLog::SetVerbose}\label{wxlogsetverbose}
9ee2d31c 302
cc81d32f 303\func{static void}{SetVerbose}{\param{bool }{ verbose = true}}
9ee2d31c 304
2edb0bde 305Activates or deactivates verbose mode in which the verbose messages are
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306logged as the normal ones instead of being silently dropped.
307
42ff6409 308\membersection{wxLog::GetVerbose}\label{wxloggetverbose}
9ee2d31c 309
4a20e756 310\func{static bool}{GetVerbose}{\void}
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311
312Returns whether the verbose mode is currently active.
313
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314\membersection{wxLog::SetLogLevel}\label{wxlogsetloglevel}
315
316\func{static void}{SetLogLevel}{\param{wxLogLevel }{ logLevel}}
317
318Specifies that log messages with $level > logLevel$ should be ignored
319and not sent to the active log target.
320
321\membersection{wxLog::GetLogLevel}\label{wxloggetloglevel}
322
323\func{static wxLogLevel}{GetLogLevel}{\void}
324
325Returns the current log level limit.
326
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327\membersection{wxLog::SetRepetitionCounting}\label{wxlogsetrepetitioncounting}
328
329\func{static void}{SetRepetitionCounting}{\param{bool }{ repetCounting = true}}
330
331Enables logging mode in which a log message is logged once, and in case exactly
332the same message successively repeats one or more times, only the number of
333repetitions is logged.
334
335\membersection{wxLog::GetRepetitionCounting}\label{wxloggetrepetitioncounting}
336
337\func{static bool}{GetRepetitionCounting}{\void}
338
339Returns whether the repetition counting mode is enabled.
340
341
22d6efa8 342\membersection{wxLog::SetTimestamp}\label{wxlogsettimestamp}
9ee2d31c 343
d993e05b 344\func{void}{SetTimestamp}{\param{const wxStrgin\&}{ format}}
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345
346Sets the timestamp format prepended by the default log targets to all
347messages. The string may contain any normal characters as well as \%
348prefixed format specificators, see {\it strftime()} manual for details.
da4b7ffc 349Passing a NULL value (not empty string) to this function disables message timestamping.
9ee2d31c 350
22d6efa8 351\membersection{wxLog::GetTimestamp}\label{wxloggettimestamp}
9ee2d31c 352
d993e05b 353\constfunc{const wxString\&}{GetTimestamp}{\void}
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354
355Returns the current timestamp format string.
356
42ff6409 357\membersection{wxLog::SetTraceMask}\label{wxlogsettracemask}
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358
359\func{static void}{SetTraceMask}{\param{wxTraceMask }{ mask}}
360
361Sets the trace mask, see \helpref{Customization}{wxlogcustomization}
362section for details.
363
42ff6409 364\membersection{wxLog::GetTraceMask}\label{wxloggettracemask}
9ee2d31c 365
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366Returns the current trace mask, see \helpref{Customization}{wxlogcustomization} section
367for details.
62448488 368
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369\membersection{wxLog::IsAllowedTraceMask}\label{wxlogisallowedtracemask}
370
5a20d2ce 371\func{static bool}{IsAllowedTraceMask}{\param{const wxString\& }{mask}}
ac7f0167 372
cc81d32f 373Returns true if the {\it mask} is one of allowed masks for
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374\helpref{wxLogTrace}{wxlogtrace}.
375
edc73852 376See also: \helpref{AddTraceMask}{wxlogaddtracemask},
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377\helpref{RemoveTraceMask}{wxlogremovetracemask}
378
379\membersection{wxLog::RemoveTraceMask}\label{wxlogremovetracemask}
380
381\func{static void}{RemoveTraceMask}{\param{const wxString\& }{mask}}
382
edc73852 383Remove the {\it mask} from the list of allowed masks for
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384\helpref{wxLogTrace}{wxlogtrace}.
385
386See also: \helpref{AddTraceMask}{wxlogaddtracemask}
387
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388%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogChain %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
389
390\section{\class{wxLogChain}}\label{wxlogchain}
391
392This simple class allows to chain log sinks, that is to install a new sink but
edc73852 393keep passing log messages to the old one instead of replacing it completely as
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394\helpref{SetActiveTarget}{wxlogsetactivetarget} does.
395
396It is especially useful when you want to divert the logs somewhere (for
397example to a file or a log window) but also keep showing the error messages
5638d705 398using the standard dialogs as \helpref{wxLogGui}{wxlogoverview} does by default.
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399
400Example of usage:
401
402\begin{verbatim}
403wxLogChain *logChain = new wxLogChain(new wxLogStderr);
404
405// all the log messages are sent to stderr and also processed as usually
406...
407
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408// don't delete logChain directly as this would leave a dangling
409// pointer as active log target, use SetActiveTarget() instead
410delete wxLog::SetActiveTarget(...something else or NULL...);
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411
412\end{verbatim}
413
414\wxheading{Derived from}
415
416\helpref{wxLog}{wxlog}
417
418\wxheading{Include files}
419
420<wx/log.h>
421
422\latexignore{\rtfignore{\wxheading{Members}}}
423
dcbd177f 424\membersection{wxLogChain::wxLogChain}\label{wxlogchainctor}
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425
426\func{}{wxLogChain}{\param{wxLog *}{logger}}
427
428Sets the specified {\tt logger} (which may be {\tt NULL}) as the default log
429target but the log messages are also passed to the previous log target if any.
430
dcbd177f 431\membersection{wxLogChain::\destruct{wxLogChain}}\label{wxlogchaindtor}
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432
433\func{}{\destruct{wxLogChain}}{\void}
434
435Destroys the previous log target.
436
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437\membersection{wxLogChain::DetachOldLog}\label{wxlogchaindetacholdlog}
438
439\func{void}{DetachOldLog}{\void}
440
441Detaches the old log target so it won't be destroyed when the wxLogChain object
442is destroyed.
443
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444\membersection{wxLogChain::GetOldLog}\label{wxlogchaingetoldlog}
445
446\constfunc{wxLog *}{GetOldLog}{\void}
447
448Returns the pointer to the previously active log target (which may be {\tt
449NULL}).
450
451\membersection{wxLogChain::IsPassingMessages}\label{wxlogchainispassingmessages}
452
453\constfunc{bool}{IsPassingMessages}{\void}
454
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455Returns {\tt true} if the messages are passed to the previously active log
456target (default) or {\tt false} if \helpref{PassMessages}{wxlogchainpassmessages}
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457had been called.
458
459\membersection{wxLogChain::PassMessages}\label{wxlogchainpassmessages}
460
461\func{void}{PassMessages}{\param{bool }{passMessages}}
462
463By default, the log messages are passed to the previously active log target.
cc81d32f 464Calling this function with {\tt false} parameter disables this behaviour
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465(presumably temporarily, as you shouldn't use wxLogChain at all otherwise) and
466it can be reenabled by calling it again with {\it passMessages} set to {\tt
cc81d32f 467true}.
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468
469\membersection{wxLogChain::SetLog}\label{wxlogchainsetlog}
470
471\func{void}{SetLog}{\param{wxLog *}{logger}}
472
473Sets another log target to use (may be {\tt NULL}). The log target specified
dcbd177f 474in the \helpref{constructor}{wxlogchainctor} or in a previous call to
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475this function is deleted.
476
477This doesn't change the old log target value (the one the messages are
478forwarded to) which still remains the same as was active when wxLogChain
479object was created.
480
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481%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogGui %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
482
483\section{\class{wxLogGui}}\label{wxloggui}
484
fc2171bd 485This is the default log target for the GUI wxWidgets applications. It is passed
a826c315 486to \helpref{wxLog::SetActiveTarget}{wxlogsetactivetarget} at the program
fc2171bd 487startup and is deleted by wxWidgets during the program shut down.
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488
489\wxheading{Derived from}
490
491\helpref{wxLog}{wxlog}
492
493\wxheading{Include files}
494
495<wx/log.h>
496
497\latexignore{\rtfignore{\wxheading{Members}}}
498
dcbd177f 499\membersection{wxLogGui::wxLogGui}\label{wxlogguictor}
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500
501\func{}{wxLogGui}{\void}
502
503Default constructor.
504
505%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogNull %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
506
507\section{\class{wxLogNull}}\label{wxlognull}
508
509This class allows to temporarily suspend logging. All calls to the log
510functions during the life time of an object of this class are just ignored.
511
fc2171bd 512In particular, it can be used to suppress the log messages given by wxWidgets
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513itself but it should be noted that it is rarely the best way to cope with this
514problem as {\bf all} log messages are suppressed, even if they indicate a
515completely different error than the one the programmer wanted to suppress.
516
517For instance, the example of the overview:
518
519{\small
520\begin{verbatim}
521 wxFile file;
522
523 // wxFile.Open() normally complains if file can't be opened, we don't want it
524 {
525 wxLogNull logNo;
526 if ( !file.Open("bar") )
527 ... process error ourselves ...
528 } // ~wxLogNull called, old log sink restored
529
530 wxLogMessage("..."); // ok
531\end{verbatim}
d2c2afc9 532}%
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533
534would be better written as:
535
536{\small
537\begin{verbatim}
538 wxFile file;
539
540 // don't try to open file if it doesn't exist, we are prepared to deal with
541 // this ourselves - but all other errors are not expected
542 if ( wxFile::Exists("bar") )
543 {
544 // gives an error message if the file couldn't be opened
545 file.Open("bar");
546 }
547 else
548 {
549 ...
550 }
551\end{verbatim}
d2c2afc9 552}%
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553
554\wxheading{Derived from}
555
556\helpref{wxLog}{wxlog}
557
558\wxheading{Include files}
559
560<wx/log.h>
561
562\latexignore{\rtfignore{\wxheading{Members}}}
563
dcbd177f 564\membersection{wxLogNull::wxLogNull}\label{wxlognullctor}
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565
566\func{}{wxLogNull}{\void}
567
568Suspends logging.
569
dcbd177f 570\membersection{wxLogNull::\destruct{wxLogNull}}\label{wxlognulldtor}
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571
572Resumes logging.
573
47fe7ff3 574%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogInterposer %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
f3845e88 575
47fe7ff3 576\section{\class{wxLogInterposer}}\label{wxloginterposer}
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577
578A special version of \helpref{wxLogChain}{wxlogchain} which uses itself as the
47fe7ff3 579new log target. It forwards log messages to the previously installed one in addition to
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580processing them itself.
581
582Unlike \helpref{wxLogChain}{wxlogchain} which is usually used directly as is,
edc73852 583this class must be derived from to implement \helpref{DoLog}{wxlogdolog}
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584and/or \helpref{DoLogString}{wxlogdologstring} methods.
585
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586wxLogInterposer destroys the previous log target in its destructor. If you
587don't want this to happen, use wxLogInterposerTemp instead.
588
589\wxheading{Derived from}
590
591\helpref{wxLogChain}{wxlogchain}
592
593\wxheading{Include files}
594
595<wx/log.h>
596
597\latexignore{\rtfignore{\wxheading{Members}}}
598
599\membersection{wxLogInterposer::wxLogInterposer}\label{wxloginterposerctor}
600
601The default constructor installs this object as the current active log target.
602
603%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogInterposerTemp %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
604
605\section{\class{wxLogInterposerTemp}}\label{wxloginterposertemp}
606
607A special version of \helpref{wxLogChain}{wxlogchain} which uses itself as the
608new log target. It forwards log messages to the previously installed one in addition to
609processing them itself. Unlike \helpref{wxLogInterposer}{wxloginterposer}, it doesn't
610delete the old target which means it can be used to temporarily redirect log output.
611
612As per wxLogInterposer, this class must be derived from to implement \helpref{DoLog}{wxlogdolog}
613and/or \helpref{DoLogString}{wxlogdologstring} methods.
614
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615\wxheading{Derived from}
616
617\helpref{wxLogChain}{wxlogchain}
618
619\wxheading{Include files}
620
621<wx/log.h>
622
623\latexignore{\rtfignore{\wxheading{Members}}}
624
47fe7ff3 625\membersection{wxLogInterposerTemp::wxLogInterposerTemp}\label{wxloginterposertempctor}
f3845e88 626
47fe7ff3 627The default constructor installs this object as the current active log target.
f3845e88 628
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629%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogStderr %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
630
631\section{\class{wxLogStderr}}\label{wxlogstderr}
632
633This class can be used to redirect the log messages to a C file stream (not to
634be confused with C++ streams). It is the default log target for the non-GUI
fc2171bd 635wxWidgets applications which send all the output to {\tt stderr}.
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636
637\wxheading{Derived from}
638
639\helpref{wxLog}{wxlog}
640
641\wxheading{Include files}
642
643<wx/log.h>
644
645\wxheading{See also}
646
647\helpref{wxLogStream}{wxlogstream}
648
649\latexignore{\rtfignore{\wxheading{Members}}}
650
dcbd177f 651\membersection{wxLogStderr::wxLogStderr}\label{wxlogstderrctor}
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652
653\func{}{wxLogStderr}{\param{FILE }{*fp = NULL}}
654
edc73852 655Constructs a log target which sends all the log messages to the given
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656{\tt FILE}. If it is {\tt NULL}, the messages are sent to {\tt stderr}.
657
658%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogStream %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
659
660\section{\class{wxLogStream}}\label{wxlogstream}
661
662This class can be used to redirect the log messages to a C++ stream.
663
fc2171bd 664Please note that this class is only available if wxWidgets was compiled with
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665the standard iostream library support ({\tt wxUSE\_STD\_IOSTREAM} must be on).
666
667\wxheading{Derived from}
668
669\helpref{wxLog}{wxlog}
670
671\wxheading{Include files}
672
673<wx/log.h>
674
675\wxheading{See also}
676
677\helpref{wxLogStderr}{wxlogstderr},\\
678\helpref{wxStreamToTextRedirector}{wxstreamtotextredirector}
679
680\latexignore{\rtfignore{\wxheading{Members}}}
681
dcbd177f 682\membersection{wxLogStream::wxLogStream}\label{wxlogstreamctor}
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683
684\func{}{wxLogStream}{\param{std::ostream }{*ostr = NULL}}
685
edc73852 686Constructs a log target which sends all the log messages to the given
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687output stream. If it is {\tt NULL}, the messages are sent to {\tt cerr}.
688
689%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogTextCtrl %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
690
691\section{\class{wxLogTextCtrl}}\label{wxlogtextctrl}
692
693Using these target all the log messages can be redirected to a text control.
694The text control must have been created with {\tt wxTE\_MULTILINE} style by the
695caller previously.
696
697\wxheading{Derived from}
698
699\helpref{wxLog}{wxlog}
700
701\wxheading{Include files}
702
703<wx/log.h>
704
705\wxheading{See also}
706
a0d43d79 707\helpref{wxTextCtrl}{wxtextctrl},\\
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708\helpref{wxStreamToTextRedirector}{wxstreamtotextredirector}
709
710\latexignore{\rtfignore{\wxheading{Members}}}
711
dcbd177f 712\membersection{wxLogTextCtrl::wxLogTextCtrl}\label{wxlogtextctrlctor}
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713
714\func{}{wxLogTextCtrl}{\param{wxTextCtrl }{*textctrl}}
715
716Constructs a log target which sends all the log messages to the given text
717control. The {\it textctrl} parameter cannot be {\tt NULL}.
718
719%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% wxLogWindow %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
720
721\section{\class{wxLogWindow}}\label{wxlogwindow}
722
723This class represents a background log window: to be precise, it collects all
724log messages in the log frame which it manages but also passes them on to the
725log target which was active at the moment of its creation. This allows, for
726example, to show all the log messages in a frame but still continue to process
727them normally by showing the standard log dialog.
728
729\wxheading{Derived from}
730
47fe7ff3 731\helpref{wxLogInterposer}{wxloginterposer}
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732
733\wxheading{Include files}
734
735<wx/log.h>
736
737\wxheading{See also}
738
739\helpref{wxLogTextCtrl}{wxlogtextctrl}
740
741\latexignore{\rtfignore{\wxheading{Members}}}
742
dcbd177f 743\membersection{wxLogWindow::wxLogWindow}\label{wxlogwindowctor}
a826c315 744
cc81d32f 745\func{}{wxLogWindow}{\param{wxFrame }{*parent}, \param{const wxChar }{*title}, \param{bool }{show = {\tt true}}, \param{bool }{passToOld = {\tt true}}}
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746
747Creates the log frame window and starts collecting the messages in it.
748
749\wxheading{Parameters}
750
751\docparam{parent}{The parent window for the log frame, may be {\tt NULL}}
752
753\docparam{title}{The title for the log frame}
754
cc81d32f 755\docparam{show}{{\tt true} to show the frame initially (default), otherwise
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756\helpref{wxLogWindow::Show}{wxlogwindowshow} must be called later.}
757
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758\docparam{passToOld}{{\tt true} to process the log messages normally in addition to
759logging them in the log frame (default), {\tt false} to only log them in the
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760log frame.}
761
762\membersection{wxLogWindow::Show}\label{wxlogwindowshow}
763
cc81d32f 764\func{void}{Show}{\param{bool }{show = {\tt true}}}
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765
766Shows or hides the frame.
767
dcbd177f 768\membersection{wxLogWindow::GetFrame}\label{wxlogwindowgetframe}
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769
770\constfunc{wxFrame *}{GetFrame}{\void}
771
772Returns the associated log frame window. This may be used to position or resize
773it but use \helpref{wxLogWindow::Show}{wxlogwindowshow} to show or hide it.
774
dcbd177f 775\membersection{wxLogWindow::OnFrameCreate}\label{wxlogwindowonframecreate}
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776
777\func{virtual void}{OnFrameCreate}{\param{wxFrame }{*frame}}
778
779Called immediately after the log frame creation allowing for
780any extra initializations.
781
782\membersection{wxLogWindow::OnFrameClose}\label{wxlogwindowonframeclose}
783
5ac9433d 784\func{virtual bool}{OnFrameClose}{\param{wxFrame }{*frame}}
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785
786Called if the user closes the window interactively, will not be
787called if it is destroyed for another reason (such as when program
788exits).
789
cc81d32f 790Return {\tt true} from here to allow the frame to close, {\tt false} to
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791prevent this from happening.
792
793\wxheading{See also}
794
795\helpref{wxLogWindow::OnFrameDelete}{wxlogwindowonframedelete}
796
797\membersection{wxLogWindow::OnFrameDelete}\label{wxlogwindowonframedelete}
798
799\func{virtual void}{OnFrameDelete}{\param{wxFrame }{*frame}}
800
801Called right before the log frame is going to be deleted: will
802always be called unlike \helpref{OnFrameClose()}{wxlogwindowonframeclose}.
803