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