Qt signal slot infinite loop

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How Qt Signals and Slots Work

How to process events during infinite loop in Worker ... I've created a Worker object in Qt to process video input indefinitely, and then move it into a QThread to keep the UI thread going. The problem is, I designed it such that the video capture function runs in an infinite loop until interrupted by a flag, and the flag was supposed to be set by a slot in the Worker object, but since the Worker object is inside the infinite loop, it never ... Qt 4.5 - Is emitting signal a function call, or a thread ... When a signal is emitted, the slots connected to it are usually executed immediately, just like a normal function call. When this happens, the signals and slots mechanism is totally independent of any GUI event loop. Execution of the code following the emit statement will occur once all slots have Qt 4.3: Signals and Slots

Qt Toolkit - Signals and Slots

I've created a Worker object in Qt to process video input indefinitely, and then move it into a QThread to keep the UI thread going. The problem is, I designed it such that the video capture function runs in an infinite loop until interrupted by a flag, and the flag was supposed to be set by a slot in the Worker object, but since the Worker object is inside the infinite loop, it never ... Signals and slots between objects in different threads in Qt Signals and slots between objects in different threads in Qt. Ask Question 0. ... I understand of your messages that I must change myprocess method because with this infinite loop the system can't process the events loop. Correct? I read the Qt documentation, but sometimes I don't know how to do it. ... Qt: Signal/Slot not working after QObject ...

How To Really, Truly Use QThreads; The Full Explanation | Maya's ...

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 parameters at the right time. Signals and slots can take any number of arguments of any type. Signals and Slots - Qt Documentation 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 parameters at the right time. Signals and slots can take any number of arguments of any type. How Qt Signals and Slots Work - Part 3 - Queued and Inter ... DirectConnection: call the slot as seen in Part 1 */ So in this blog post we will see what exactly happens in queued_activate and other parts that were skipped for the BlockingQueuedConnection. Qt Event Loop. A QueuedConnection will post an event to the event loop to eventually be handled. Signal and slot to synchronize variable between qthread | Qt ... The signal and slot approach works well when the objects live in the same thread, but in this case it generates a loop as you can see in the output. What I'm expecting is the first 4 rows of the output and stop, but with this code the output is an infinite loop. Thank you for your help. V. myclass.cpp

Event loops and signal-slot processing when using…

Infinite loop and signal deluge Infinite loop and signal deluge. This topic has been deleted. ... and connect this signal in a blocking way to a slot of my main thread that will just consist in a processEvents() call. Reply Quote 0. 0 Replies Last reply . ... Nokia Certified Qt Specialist. Signals and Slots - Qt Documentation Signals and Slots. 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. In GUI programming we often want a change in one widget to be notified to another widget. Signal Slot problem in a thread [EDIT-UPDATE] | Qt Forum @VRonin said:. I thought the order of execution of slots should not be considered deterministic. When across threads it can't be deterministic. When using Qt::DirectConnection (I think it's documented) the order is in the order of connects.. Or does that rely on the fact that the first connection is implicitly a directconnection while the second is a queuedconnection? if that is the case then ...