Qt signal slot with return value

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The following simple code snippet shows how to create and use QPushButton. It has been tested on Qt Symbian Simulator. An instance of QPushButton is created. Signal released() is connected to slot handleButton() which changes the text and the size of the button. To build and run the example: Create an empty folder

Signals and slots are used for communication between objects. 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. The minimal example requires a class with one signal, one slot and one connection: counter.h [QTBUG-23488] Socket options return strange values - Qt ... On Windows 7 with Qt 4.8, socket options for KeepAlive and LowDelay always return value -256. It doesn't change when we enable or disable this option. On Ubuntu 11.10 with Qt 4.7.4, these options always return 0. Maybe I'm doing something wrong, but here's a code to test it. Eigenen Slot und Signal definieren... - qtforum.de

How to Expose a Qt C++ Class with Signals and Slots to QML

Feb 7, 2010 ... Outside observers can use the finished() signal to know when your thread is actually done. ... timer->start(0); exec(); // starts the event loop, and doesn't // return until it is told ... The stop() method must be a slot in MyThread (and not just a ... the real work: #define THREAD_MAGIC(targetThread, returnValue, ... [Quick PyQt5 : 1] Signal and Slot Example in PyQt5 – Manash's blog

Can Qt signals return a value? - ExceptionsHub

the vector _a is a list of arguments that is passed to qt_metacall. 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. Qt 시그널 슬롯 시스템이란? :: I will be Great Software Engineer

Signal/Slot with return value doesn't work - Stack Overflow

Signals and slots are loosely coupled: A class which emits a signal neither knows nor cares which slots receive the signal. 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 c++ - QT return value from a signal? - Stack Overflow I'm running all my SQLite database operations in a separate thread to ensure that the GUI wont freeze up. I'm doing this by connecting up signals and slots for the methods. Return value from slot in differnet thread | Qt Forum 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. I know that slots should be void and should not be used for this, even if they seem to do it