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Improve QLoggingCategory's detailed description. 

Change-Id: I40527890fb752c3a1c0f8d8a8fa4ca2b19e4fc08
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>
bb10
Mitch Curtis 2014-10-16 21:53:35 +02:00 committed by Mitch Curtis
parent 28857e7ad0
commit d0402bed6f
1 changed files with 13 additions and 10 deletions
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23
src/corelib/io/qloggingcategory.cpp
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@ -61,13 +61,15 @@ static void setBoolLane(QBasicAtomicInt *atomic, bool enable, int shift)
\brief The QLoggingCategory class represents a category, or 'area' in the
logging infrastructure.
QLoggingCategory represents a certain logging category - identified
by a string - at runtime. Whether a category should be actually logged or
not can be checked with the \l isEnabled() methods.
QLoggingCategory represents a certain logging category - identified by a
string - at runtime. A category can be configured to enable or disable
logging of messages per message type. Whether a message type is enabled or
not can be checked with the \l isDebugEnabled(), \l isWarningEnabled(), and
\l isCriticalEnabled() methods.
All objects are meant to be configured by a common registry (see also
\l{Configuring Categories}). Different objects can also represent the same
category. It's therefore not recommended to export objects across module
category. It is therefore not recommended to export objects across module
boundaries, nor to manipulate the objects directly, nor to inherit from
QLoggingCategory.
@ -110,8 +112,9 @@ static void setBoolLane(QBasicAtomicInt *atomic, bool enable, int shift)
\section2 Logging Rules
Logging rules allow to enable or disable logging for categories in a flexible
way. Rules are specified in text, where every line must have the format
Logging rules allow logging for categories to be enabled or disabled in a
flexible way. Rules are specified in text, where every line must have the
format
\code
<category>[.<type>] = true|false
@ -120,12 +123,12 @@ static void setBoolLane(QBasicAtomicInt *atomic, bool enable, int shift)
\c <category> is the name of the category, potentially with \c{*} as a
wildcard symbol as the first or last character (or at both positions).
The optional \c <type> must be either \c debug, \c warning, or \c critical.
Lines that do not fit to his scheme are ignored.
Lines that do not fit this scheme are ignored.
Rules are evaluated in text order, from first to last. That is, if two rules
apply to a category/type, the rule that comes later is applied.
Rules can be set via \l setFilterRules(). Since Qt 5.3 logging rules can also
Rules can be set via \l setFilterRules(). Since Qt 5.3, logging rules can also
be set in the \c QT_LOGGING_RULES environment variable, and
are automatically loaded from the \c [Rules] section of a logging
configuration file. Such configuration files are looked up in the QtProject
@ -168,13 +171,13 @@ static void setBoolLane(QBasicAtomicInt *atomic, bool enable, int shift)
\section2 Installing a Custom Filter
As a lower-level alternative to the text rules you can also implement a
As a lower-level alternative to the text rules, you can also implement a
custom filter via \l installFilter(). All filter rules are ignored in this
case.
\section1 Printing the Category
Use the \c %{category} place holder to print the category in the default
Use the \c %{category} placeholder to print the category in the default
message handler:
\snippet qloggingcategory/main.cpp 3