Well, a slot an return a value because it is also a normal C++ method. But the return value is only accessible when called as such, not when called through signal/slots. Yes, quite true, but I was thinking only in the signals/slots context. Most times, my normal thinking is... Can Qt signals return a value? Вот почему. Qt Сигналы синтаксис обсахаренного интерфейса для шаблона сигнализации. Слоты являются получателями сигнала.foreach slot in connectedSlotsForSignal(signal): value = invoke slot with parameters from signal return value. Очевидно, что MOC делает немного больше... QT: работаем с сигналами и слотами QT: работаем с сигналами и слотами. Этот "классический" слегка доработанный пример на сигналы и слоты в QT показывает, как их соединять, как разрывать и возобновлять соединение. Сначала немного теории. В QT реализована концепция функций обратного вызова... c++ - Может ли сигналы Qt возвращать значение?
Functions specifically for signals/slots
Qt: Signals & Slots - PUC-Rio Signals and slots are loosely coupled: A class which emits a signal neither knows nor cares which slots receive the signal. Qt's signals and slots mechanism ensures that if you connect a signal to a slot, the slot will be called with the signal's parameters at the right time. Signals and slots can take any number of arguments of any type. PySide/PyQt Tutorial: Using Built-In Signals and Slots ... This signal does nothing, by itself; it must be connected to a slot, which is an object that acts as a recipient for a signal and, given one, acts on it. Connecting Built-In PySide/PyQt Signals. Qt widgets have a number of signals built in. For example, when a QPushButton is clicked, it emits its clicked signal. Interacting with QML Objects from C++ | Qt QML 5.9 Connecting to QML Signals. All QML signals are automatically available to C++, and can be connected to using QObject::connect() like any ordinary Qt C++ signal. In return, any C++ signal can be received by a QML object using signal handlers. Here is a QML component with a signal named qmlSignal that is Qt 4.8: QDialog Class Reference
For calling slots, we may have to perform conversion both ways; converting arguments from JS to C++, and converting the slot's return value back to JS.
Qt Signals and Slots Qt Signals and Slots. Olivier Goart October 2013. About Me.Qt 4. Thread support QueuedConnection Meta type registration Several major internal changes Added le and line number information in debug mode But still no changes in the syntax.
Signals and Slots. In Qt, we have an alternative to the callback technique: We use signals and slots. A signal is emitted when a particular event occurs. Qt's widgets have many predefined signals, but we can always subclass widgets to add our own signals to them. A slot is a function that is called in response to a particular signal.
Signals and Slots in PySide - Qt Wiki
Qt Signals - это синтаксический сахаризованный интерфейс для шаблона сигнализации. Слоты являются получателями сигнала.foreach slot in connectedSlotsForSignal(signal): value = invoke slot with parameters from signal return value. Очевидно, что moc делает немного больше, чтобы...
It captures the return value from the slots. Expand the code”testSlot2″, and return the last value from the connected slots of the signal. Qt Signals are a syntax sugared interface to the signaling pattern. Slots are the recipients of signal and direct connected signal-slot relationship.
Boost.Signals allows various strategies of using the return values of slots to form the return value of the signal. E.g. adding them, forming a vector out of them, or returning the last one. The common wisdom (expressed in the Qt documentation [EDIT: as well as some answers to this question...