QVector<QComboBox*> signal and slot problem | Qt Forum That would do what you want, but if the slot has access to the QVector you don't need to set the property, just lookup the index using the pointer.[/quote] Hi Seamus Boyle, Since my signal is currentIndexChange(QString). QSignalMapper Class | Qt Core 5.12.3 A list of texts is passed to the constructor. A signal mapper is constructed and for each text in the list a QPushButton is created. We connect each button's clicked() signal to the signal mapper's map() slot, and create a mapping in the signal mapper from each button to the button's text. How Qt Signals and Slots Work - Part 2 - Qt5 New Syntax QObject::connect(const QObject *sender, PointerToMemberFunction signal, Functor method) The first one is the one that is much closer to the old syntax: you connect a signal from the sender to a slot in a receiver object. The two other overloads are connecting a signal to a static function or a functor object without a receiver. I STRONGLY NEED to know slot where signal is connected to.
Can a signal call a non-slot method | Qt Forum
A Qt way: Automatic Connections: using Qt signals and ... Automatic Connections: using Qt signals and slots the easy way One key and distinctive feature of Qt framework is the use of signals and slots to connect widgets and related actions. But as powerful the feature is, it may look compelling to a lot of developers not used to such a model, and it may take some time at the beginning to get used to ... 1] Signal and Slot Example in PyQt5 - Manash’s blog Signal-Slot is one of the fundamental topics of Qt one should have a firm grasp to write Qt applications. I have been developing Qt C++ application on Windows/Linux platforms about 3 and a half year so I know a bit about signal-slot and how to connect and disconnect them.
Connecting in Qt 5. There are several ways to connect a signal in Qt 5. Old syntax. Qt 5 continues to support the old string-based syntax for connecting signals and slots defined in a QObject or any class that inherits from QObject (including QWidget) . connect( sender, SIGNAL( valueChanged( QString, QString ) ), receiver, SLOT( updateValue( QString ) ) );
@Pablo-J.-Rogina said in Reasons for signal/slot connection with sender == receiver? @Bart_Vandewoestyne said in Reasons for signal/slot connection with sender == receiver?. But in the code I'm reviewing, fooSignal is only connected to fooSlot. Do you mean in the same class or in the whole project?
qt - Can I have one slot for several signals? - Stack Overflow
Would it be a solution to hold a pointer to your thread in your app, let thread signal the end of your thread, connect (to your Qt MainThread) and delete in slot. (If you are already in Mainthread you don't have to wait till deleteLater). Or, if you have to wait, dont delete the object, but flag it and delete flagged objects whenever you want. Signals & Slots | Qt 4.8
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.A slot is a receiving function used to get information about state changes in other widgets. LcdNumber uses it, as the code above indicates, to set the...
c++ - QRunnable emit signal and get sender from slot QRunnable is destroyed by QThreadPool after it finishes. When I emit a signal from it and try to get the QRunnable object from slot using sender() it's NULL. Minimal example: // class MyRunnable : c++ - Qt: Signal main thread - Stack Overflow I can emit from this thread, but only if I connect the slot using Qt::DirectConnection. The upshot is that QObject::sender() in the SLOT will always return NULL. I wish to call deleteLater() for instance, but that can only be scheduled in a QThread. I think I need to get back to the main thread, but how can I signal the object on the main thread? Signals & Slots | Qt Core 5.12.3
Deleting the signal sender from a slot The deletion happens from a slot connected to that signal. My understanding has always been that such a thing is not allowed.Qt Centre is a community site devoted to programming in C++ using the Qt framework. Over 90 percent of questions asked here gets answered. qt4 qt - How to get sender widget with a signal/slot... -… So, is there a way to understand which widget sends the signal? I'm looking for something like sender argument of events in .NET.Yes, you can connect multiple signals to one slot. In this case you would use QSignalMapper to differentiate the sources of the signals. Qt Signals And Slots - Programming Examples Connecting Signals and Slots. Features. Examples. Objectives. Learn the advantages of signals/slots.Learn how to connect signals to slots. Be able to use and define your own signals/slots. Meta-Object System. Extends C++ with dynamic features.