Notice the Q_RETURN_ARG() and Q_ARG() arguments for QMetaObject::invokeMethod() must be specified as QVariant types, as this is the generic data type used for QML functions and return values. To call a C++ function from QML, the function must be either a Qt slot, or a function marked with the Q_INVOKABLE macro, to be Qt 4.2: QDialog Class Reference - cep.xray.aps.anl.gov The most common way to display a modal dialog is to call its exec() function. 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. QSslSocket — Qt for Python - doc-snapshots.qt.io If no SSL support is available then this will return an empty value. PySide2.QtNetwork.QSslSocket.startClientEncryption ¶ Starts a delayed SSL handshake for a client connection. This function can be called when the socket is in the ConnectedState but still in the UnencryptedMode. If it is not yet connected, or if it is already encrypted, this ... How can I get return values from slot function? Several ...
Getting a return value from an emitted signal | Qt Forum
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. Package 'qtbase' methods and extending 'Qt' classes from R. Other packages build upon 'qtbase' .... These functions construct some simple Qt helper objects. ... the values are double, a QSizeF instance is returned, otherwise an instance of QSize. .... qslots returns a similar data.frame containing only slot methods and the columns name, ... qtlua/qt.md at master · torch/qtlua · GitHub 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 Thread - [0] - 博客园
Signals & Slots — Qt for Python
Feb 13, 2012 ... Debugging Qt's signal-slot connections… ... If need be, ensure that connect succeeds by testing its return value (it should ... Make sure you make the connection with connect before you invoke any functions that fire the signal. How to Expose a Qt C++ Class with Signals and Slots to QML - Felgo This guide shows how to enhance your C++ class with signals and slots for ... In other words, we want to trigger functions in QML when the C++ property changes. .... No further adjustments are required to receive the return value in QML. Qt ... Signals and Slots | Introduction to GUI Programming with Python and Qt Feb 8, 2008 ... In C++/Qt, slots are methods that must be declared with a special syntax; ... If the values are the same, we do nothing and return; otherwise, we apply .... If we use the SIGNAL() function with a signalSignature (a possibly empty ... Lambda Expressions and Qt 4.x - Silmor.de Writing a complete function just for a custom sorting is quite cumbersome and .... are copied (the lambda knows its context by value instead of by reference), but ... If you need the paramters or need a return type for the slot/lambda you have to ...
QGlib - GStreamer
While developing with Qt Signal/Slots, I came across a few segmentation faults that had me puzzled as to what was causing it. Eventually I figured out that you could actually pass a slot function without providing it any of its arguments, which of course would cause a Segmentation Fault if the argument... Qt 4.5: Signals and Slots
Hi I have a function I use to init a socket in a different thread/class. I'd like to get a return value that tells me in the main/GUI thread if everything is ok.
QDialog Class | Qt Widgets 5.12.3
Nov 23, 2014 ... Signals and Slots are a feature of Qt used for communication ... the GUI with a progress bar, then kick off a function to handle this input. ... I will emit the signal when the button is pressed, passing the value of the text field. Support for Signals and Slots — PyQt 5.11.1 Reference Guide One of the key features of Qt is its use of signals and slots to communicate between objects. ... that is the signature of the signal that would be returned by Qt's SIGNAL() macro. .... PyQt5 provides the pyqtSlot() function decorator to do this. ... def valueChanged(self, value): """ Two slots will be defined in the QMetaObject. """ ... Debugging Qt's signal-slot connections… – Ray Rischpater, KF6GPE Feb 13, 2012 ... Debugging Qt's signal-slot connections… ... If need be, ensure that connect succeeds by testing its return value (it should ... Make sure you make the connection with connect before you invoke any functions that fire the signal. Qt: meaning of slot return value? - Stack Overflow