Qt can slots return value

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Combining Qt’s Signals and Slots with c++0x lamdas

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 ... Getting a return value from an emitted signal | Qt Forum Getting a return value from an emitted signal ... If you need a return value, ... There's at least two things that can happen that can mess things up: Multiple slots ... Return value from slot in differnet thread | Qt Forum I'd like to get a return value that tells me in the main/GUI thread if everything is ok. I know that slots should be ... Return value from slot in differnet thread. Signals & Slots | Qt 4.8 Qt's signals and slots mechanism ensures that if you connect a signal to a ... { return m_value; } public slots: void setValue ... They can never have return types ...

The signals and slots mechanism is a central feature of Qt and probably the part that differs most from the features provided by other frameworks.Slots can be used for receiving signals, but they are also normal member functions. Just as an object does not know if anything receives its signals, a slot does...

Qt 4.8: QDialog Class Reference The QDialog class is the base class of dialog windows. A dialog window is a top-level window mostly used for short-term tasks and brief communications with the user. QDialogs may be modal or modeless. QDialogs can provide a return value, and they can have default buttons.

Your slots can return a value. However, if the slot is connected to a signal and called when the signal is emitted, the return value will be ignored. 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 :

Signal and Slots - kjellkod - Google Sites Signal and slots is a concept developed from Qt. It is basically a generalized ..... within an object. can return values collected from multiple slots, no return.

Return value of this function can be used for creating Qt connections using qt_core::connection API. fn select_all (&self) -> SelectAll Returns an object representing a built-in Qt slot QSpinBox::selectAll .

c++ - Qt: meaning of slot return value? - Stack Overflow This is passed by QMetaObject::invokeMethod. So the return value in the moc generated code is saved and passed back to the caller. So for normal signal-slot interactions the return value is not used for anything at all. However, the mechanism exists so that How can I return a value from SLOT in Qt5? - Stack Overflow I have to return the QString in the slot to the newServerConn() function and from there to a function in MainWindow class because only then I would be able to print the string to the plainLineEdit widget pointed by the ui object. Question 1: How can I return a c++ - Can Qt signals return a value? - Stack Overflow 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