Qt can slots return value

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Qt хорошо известен своим механизмом сигналов и слотов. Но как это работает? В этом посте мы исследуем внутренности QObject и QMetaObject и раскроем их работу за кадром.Вызов слота. Также возможно вызвать слот по его индексу, используя функцию qt_static_metacall

PyQt/Sending Python values with signals and slots - Python ... Sending Python values with signals and slots. On the #pyqt channel on Freenode, Khertan asked about sending Python values via Qt's signals and slots mechanism. The following example uses the PyQt_PyObject value declaration with an old-style signal-slot connection, and again when the signal is emitted, to communicate a Python dictionary. qt_widgets::check_box::connection::Slots - Rust Returns an object representing a built-in Qt slot QCheckBox::toggle. Return value of this function can be used for creating Qt connections using qt_core::connection API. fn animate_click(&self) -> AnimateClick. Returns an object representing a built-in Qt slot QCheckBox::animateClick. qt_widgets::spin_box::connection::Slots - Rust Returns an object representing a built-in Qt slot QSpinBox::clear. Return value of this function can be used for creating Qt connections using qt_core::connection API. fn set_value(&self) -> SetValue. Returns an object representing a built-in Qt slot QSpinBox::setValue. qt_widgets::table_view::connection::Slots - Rust

Signals and slots are used for communication between objects. The signal/ slot mechanism is a central feature of Qt and probably the part that differs most from other toolkits.Signals and slots can take any number of arguments of any type. They are completely typesafe: no more callback core dumps!

c++ connect - Qt:meaning of slot return value? - CODE Solved 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 return values from slots can be accessed if the slot is called via invokeMethod. Slot with return value called via Signal between differen Threads

Qt for beginners — Finding information in the documentation. Qt documentation is a very valuable piece of information. It is the place to find everything related to Qt. But, Qt documentation is not a tutorial on how to use Qt. It is a collection of all information related to classes, as well as some examples.

The return value is used when making syncrhonous calls across threads inside a Qt application (supported via invokeMethod and settingI 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. Qt Signals & Slots: How they work | nidomiro

How Qt Signals and Slots Work - Part 2 - Qt5 New Syntax

Modal dialogs are often used in situations where a return value is required, e.g. to indicate whether the user pressed OK or Cancel. A dialog can be closed by calling the accept() or the reject() slots, and exec() will return Accepted or Rejected as appropriate. The exec() call returns the result of the dialog. 20 ways to debug Qt signals and slots | Sam Dutton’s blog 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.