Qt slot function return value

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Below are some suggestions for troubleshooting signals and slots in the Qt C++ library. 1. Check for compiler warnings about non-existent signals and/or slots. 2. Use break points or qDebug to check that signal and slot code is definitely reached: - the connect statement - code where the signal is fired - the slot code. 3. Check…

Qwt User's Guide: QwtAbstractSlider Class Reference Qwt - Qt Widgets for Technical Applications .... Public Slots | Signals | Public Member Functions | Protected Member Functions | List ... Returns the current value. qobject.cpp source code [qtbase/src/corelib/kernel/qobject.cpp ... 654, \brief The QObject class is the base class of all Qt objects. 655. 656, \ingroup ...... 2441, \warning The return value of this function is not valid when the slot. Making Boost.Signals2 More OOP‐Friendly - The Hermetic Vault 17 Apr 2015 ... Or think of Qt signals and slots or Visual C++ event handling, but .... The function returns boost::signals2::connection object which can be used ...

Below are some suggestions for troubleshooting signals and slots in the Qt C++ library. 1. Check for compiler warnings about non-existent signals and/or slots. 2. Use break points or qDebug to check that signal and slot code is definitely reached: - the connect statement - code where the signal is fired - the slot code. 3. Check…

How C++ lambda expressions can improve your Qt code - Medium Jan 25, 2017 ... We can use this lambda in a function like std::transform() to ... for(int value : vect) { std::cout << value << std::endl; } return 0; } .... public slots:

QObject is the base class to most Qt classes. ..... A callback is a pointer to a function that is called ... A slot can return values, but not through connections. ○.

I think that the return value for a slot is only available when the function is called directly (when it is a normal C++ function) or when using invokeMethod. I think this is really meant for internal Qt functions rather than for normal use in programs using Qt. Edit: For the sample case [Qt-jambi-interest] QList and function return value

For certain functions, you need a return value. This will not work as easily in slots. In slots you cant use the return value of a function or give a reference parameter to them. Yes you can do it, but you have a timing Problem. Whether you're using a slot or a normal member function dependents on your software architecture.

QDialog Class | Qt 4.8 When the user closes the dialog, exec() will provide a useful return value. Typically, to get the dialog to close and return the appropriate value, we connect a default button, e.g. OK, to the accept() slot and a Cancel button to the reject() slot. Alternatively you can call the done() slot with Accepted or Rejected. c++ - Qt: meaning of slot return value? - Stack Overflow I think that the return value for a slot is only available when the function is called directly (when it is a normal C++ function) or when using invokeMethod. I think this is really meant for internal Qt functions rather than for normal use in programs using Qt. Edit: For the sample case:

QSslSocket — Qt for Python - doc-snapshots.qt.io

Signals are connected by calling the signal's connect() member function. ... 3Other signal/slot approaches do allow values to be returned, but I found this to be .... I wrote the sigslot library because, after some time programming in the Qt ... Lambda Expressions and Qt 4.x - Silmor.de