QTraceGuard Class
The QTraceGuard class facilitates notifications to QTracer objects. More...
Header: | #include <QTraceGuard> |
qmake: | QT += core |
Since: | Qt 5.2 |
Detailed Description
The QTraceGuard class facilitates notifications to QTracer objects.
QTraceGuard objects are typically implicitly created on the stack when using the qCTrace or qCTraceGuard macros and are associated to a QLoggingCategory.
The constructor of a QTraceGuard objects checks whether its associated category is enabled, and if so, informs all QTracer objects registered with the category that a tracing activity starts.
The destructor of a QTraceGuard objects checks whether its associated category is enabled, and if so, informs all QTracer objects registered with the category that a tracing activity ended.
A QTraceGuard object created by qCTrace will be destroyed at the end of the full expression, a guard created by qCTraceGuard at the end of the block containing the macro.
During the lifetime of a QTraceGuard object, its operator<<() can be used to pass additional data to the active tracers. The fast path handles only int and const char * data, but it is possible to use arbitrary values wrapped in QVariants.
See also QTracer.