All the information (slot to call, parameter values, ...) are stored inside the event. Copying the parameters. The argv coming from the signal is an array of pointers to the arguments. The problem is that these pointers point to the stack of the signal where the arguments are. Once the signal returns, they will not be valid anymore. Qt signals and slots for newbies - Qt Wiki Connections can be added or removed at any time during the execution of a Qt application, they can be set up so that they are executed when a signal is emitted or queued for later execution, and they can be made between objects in different threads. QThreads general usage - Qt Wiki Whether it are Win32, POSIX or other threads, they all basically work the same and are quite fool-proof. Those who have discovered the joys of the Qt framework may assume that threads in Qt are just like this, and they would be right. However, there are several different ways to use threads in Qt, and it might not be obvious which approach to ...
user interface - Qt signaling across threads, one is GUI ...
Feb 2, 2017 ... When using the Qt framework in a multi-threaded application, it is ... in some way with the QObject or their data for various reasons. ... but only the slots of A and only when invoked by a signal through a non-direct connection. Helloworld922's Blog: Thread-Safe Signals/Slots using C++11 Jul 23, 2013 ... However, it relied on the Qt Moc pre-compiler tool, which meant any ... Signals may be invoked from multiple threads, and usually can be ... Qt fundamentals - BlackBerry Native
Below are some suggestions for troubleshooting signals and slots in the Qt C++ library. 1. Check for compiler warnings about non-existent signals and/or3. Check that the parameter types of the signal and slot are exactly correct and, as appropriate, that they match. 4. Make sure you haven’t added a...
I am not sure about the nature of the signal/slot mechanism in Qt 4.5. When a signal is emitted, is it a blocking function call or a thread? Say this emit GrabLatestData(); // proceed with latest...
Signals and Slots. Qt's signals and slots mechanism ensures that if you connect a signal to a slot, the slot will be called with the signal's parameters at the right time. Signals and slots can take any number of arguments of any type. They are completely type safe.
Feb 2, 2017 ... When using the Qt framework in a multi-threaded application, it is ... in some way with the QObject or their data for various reasons. ... but only the slots of A and only when invoked by a signal through a non-direct connection.
connect(button, SIGNAL (clicked()), qApp, SLOT (quit())); Connections can be added or removed at any time during the execution of a Qt application, they can be set up so that they are executed when a signal is emitted or queued for later execution, and they can be made between objects in different threads.
Cannot connect signal and slot from different thread. | Qt ... @Wuzi said in Cannot connect signal and slot from different thread.. Qt::QueuedConnection will be made automatically when I create a connection between two threads or do I have to set it explizit? It is done automatically if you connect after moving to thread. c++ : Qt Can't Have Model and View on different Threads? I don't know much about threading stuff yet, but your explanation for this looks fairly reasonable too me. From my reading of it, the signal/slot connections between the model and view have to be made with Qt::DirectConnection. However, making connections across threads would have to be Qt::QueuedConnection. Problem with signal-slot connection across threads [SOLVED ... Problem with signal-slot connection across threads [SOLVED] Problem with signal-slot connection across threads [SOLVED] This topic has been deleted. Only users with topic management privileges can see it. ... So basically once I want cross thread signals and slots, I need an event loop on the thread with the slots?[/quote]Correct. ... Qt 4.5 - Is emitting signal a function call, or a thread ...
Signals & Slots | Qt Core 5.12.3 Signals and Slots. Qt's signals and slots mechanism ensures that if you connect a signal to a slot, the slot will be called with the signal's parameters at the right time. Signals and slots can take any number of arguments of any type. They are completely type safe. Synchronizing Threads | Qt 5.12 The thread that the signal receiver lives in will then run the slot. Alternatively, call QMetaObject::invokeMethod () to achieve the same effect without signals. In both cases, a queued connection must be used because a direct connection bypasses the event system and runs the method immediately in the current thread. Cannot connect signal and slot from different thread. | Qt ... @Wuzi said in Cannot connect signal and slot from different thread.. Qt::QueuedConnection will be made automatically when I create a connection between two threads or do I have to set it explizit? It is done automatically if you connect after moving to thread. c++ : Qt Can't Have Model and View on different Threads?