diff options
Diffstat (limited to 'src/corelib/kernel/qobject.cpp')
| -rw-r--r-- | src/corelib/kernel/qobject.cpp | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp index 4304add49c6..e2c73d58ab7 100644 --- a/src/corelib/kernel/qobject.cpp +++ b/src/corelib/kernel/qobject.cpp @@ -4855,6 +4855,28 @@ QDebug operator<<(QDebug dbg, const QObject *o) */ /*! + \macro QT_NO_CONTEXTLESS_CONNECT + \relates QObject + \since 6.7 + + Defining this macro will the overload of QObject::connect() that + connects a signal to a functor, without also specifying a QObject + as a receiver/context object (that is, the 3-arguments overload + of QObject::connect()). + + Using the context-less overload is error prone, because it is easy + to connect to functors that depend on some local state of the + receiving end. If such local state gets destroyed, the connection + does not get automatically disconnected. + + Moreover, such connections are always direct connections, which may + cause issues in multithreaded scenarios (for instance, if the + signal is emitted from another thread). + + \sa QObject::connect, Qt::ConnectionType +*/ + +/*! \typedef QObjectList \relates QObject @@ -4959,6 +4981,11 @@ void qDeleteInEventHandler(QObject *o) However, you should take care that any objects used within the functor are still alive when the signal is emitted. + For this reason, it is recommended to use the overload of connect() + that also takes a QObject as a receiver/context. It is possible + to disable the usage of the context-less overload by defining the + \c{QT_NO_CONTEXTLESS_CONNECT} macro. + Overloaded functions can be resolved with help of \l qOverload. */ |