Here is how you would connect a signal to a slot: Qt will indeed call directly the function pointer of the slot, and will not need moc. The Qt signals/ slots and property system are based on the ability to introspect the objects at runtime. Introspection means being able to list the. Signale und Slots sind ein Mechanismus von Qt, wie sich verschiedene GUI- Elemente oder Aktionen unterhalten können. Jemand sendet ein Signal aus und. They are completely type safe. This will emit the second signal immediately whenever the first is emitted. Signals and Slots In Qt, we have an alternative to the callback technique: For each function, moc also saves the return type of each parameter, their type and index to the name. There is no magic involved and this blog post will show you how it works. Here is an annotated version of its implementation from qobject. In connect wird auch geprüft, ob die angegebenen Signale und Slots existieren und ob die Typen der Parameter übereinstimmen. They are simple functions that just create an array of pointers to the arguments and pass that to QMetaObject:: The signals and slots mechanism is type safe: Some destructors and member functions are omitted here; the moc ignores member functions. In each QMetaObject, the slots, signals and other invokable methods of that object are given an index, starting from 0. The processing function then calls the callback when appropriate. The staticMetaObject is constructed in the read-only data. Sign up using Email and Password.