If one needed to listen to a signal just once, one had to store the QMetaObject::Connection object returned by connect() and use it to disconnect the slot after the first signal activation. This has led to a proliferation of using wrappers (and enough TMP); they usually look like this: 1) create a shared_ptr<QMO::Connection>, allocating its payload; 2) create a lambda, capturing the shared_ptr by value; 3) in the lambda, disconnect the connection (through the shared_ptr), and call the actual slot; 4) connect the signal to the lambda, storing the returned QMO::Connection into the shared_ptr. This is expensive, error prone for newcomers, and tricky to support as a general facility inside one's projects. We can do better, just support single shot connections right in QObject. [ChangeLog][QtCore][QObject] Added the Qt::SingleShotConnection flag. When a connection is established with this flag set, the slot is going to be activated at most once; when the signal is emitted, the connection gets automatically broken by Qt. Change-Id: I5f5feeae7f76c9c3d6323d841efba81c8f98ce7e Fixes: QTBUG-44219 Reviewed-by: Lars Knoll <lars.knoll@qt.io> Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de> |
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| cmake | ||
| concurrent | ||
| corelib | ||
| dbus | ||
| gui | ||
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| installed_cmake | ||
| network | ||
| opengl | ||
| other | ||
| printsupport | ||
| shared | ||
| sql | ||
| testlib | ||
| tools | ||
| widgets | ||
| xml | ||
| .prev_CMakeLists.txt | ||
| CMakeLists.txt | ||
| auto.pro | ||
| network-settings.h | ||