Qt slot function return value

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All properties, slots and signals declared by the C++ Qt objects are ... Function qtdata:tostring() returns a Lua string representing the value contained in the Qt ...

QT signal and slot function signature. But the slot is a normal member function and can be called like any other function. In this case, the return value can be used by the caller. This is said in the document you link to : Since slots are normal member functions, they follow the normal C++ rules when called directly. c++ - QT return value from a signal? - Stack Overflow I'm running all my SQLite database operations in a separate thread to ensure that the GUI wont freeze up. I'm doing this by connecting up signals and slots for the methods. However now I need to Slot doesnt exist in connect function in C++/Qt project

Signals & Slots | Qt 4.8

How to Bind a QML Property to a C++ Function - Qt Wiki At the moment Qt Quick does not provide an implementation for linking a QML property to the result of a C++ function. There exists a suggestion for adding support for this though. In this article we will show how to make binding of properties to C++ functions work using Q_PROPERTY with a NOTIFY signal that is emitted whenever the value of the ...

Looking through the Qt source it seems that when a slot is called from QMetaObject::invokeMethod the return type can be specified and the return value obtained. (Have a look at invokeMethod in the Qt help) I could not find many examples of this actually being used in the Qt source. One I found was.

Public Member Functions ... Return the value of this Property as a QVariant. If the value .... This should be a Qt slot specification, generated by Qt's SLOT() macro. CommonQt - Common-Lisp.net! CommonQt is a Common Lisp binding to the smoke library for Qt. ... The function CONNECT is used to connect signals and slots in different ways: ... either call- next-qmethod can be used, when the return value is needed, or stop-overriding can ...

QMetaMethod Class | Qt Core 5.12.3

This value is used in QTableView::sizeHintForColumn(), QTableView::sizeHintForRow() and QTreeView::sizeHintForColumn(). Reimplementing these functions can make this function not having an effect. QTextBrowser Class | Qt Widgets 5.12.3 [virtual slot] void QTextBrowser:: forward() QQuickWidget Class | Qt Quick 5.12.3

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.

QMetaMethod Class | Qt Core 5.12.3 The return value of this method call is placed in returnValue. If the invocation is asynchronous, the return value cannot be evaluated. You can pass up to ten arguments (val0, val1, val2, val3, val4, val5, val6, val7, val8, and val9) to this method call. QGenericArgument and QGenericReturnArgument are internal helper classes.