C++ GUI Programming with Qt 4. Jasmin Blanchette. Mark Summerfield. In association with Trolltech Press. Upper Saddle River, NJ Boston Indianapolis San Francisco. Communicating with the Main Thread. Layout automatically assigns reasonable positions and sizes to the widgets for which it is. Qt4 update gui thread count. In order to switch between processes, the current program counter is saved and the next processor's program counter is loaded. This thread is called the 'main thread' also known as the 'GUI thread' in Qt applications. Program counter and registers of inactive.

Hi everyone, I've got a poser here. I use the QCustomPlot in a good old desktop application to my full satisfaction.

But now I need to extend the user interface to the web, I'd like to take the qualities of the QCP with me. Maybe I'm not the first one to try this, maybe some of you out there (or you, derManu) have already thought about this or even better have it done. So the thing is: Is it possible to run QCustomPlot outside the GUI thread to paint the plot on, say, a QImage? The first task is clear - to get rid of the QWidget and substitute the geometry, events etc. This one is clear and I'm already half way through. But before I'll dig deep into the 'Paint It Black' stuff, I just wanted to ask advice.

I myself am not an expert on painting in threads in Qt and will much appreciate any sort of advice / help / ready-made QCP-in-Threads source as well as a possible no-go warning. Thanks in advance! I have the same need: I'm using QCustomPlot in a scientific application and think is does a really great job -- many thanks! I now need to process a large amount of data on a remote machine and want to generate plots (in png or pdf format) to monitore the progress. It would be great to have a way of using the main functionality without having to run a GUI. I'm afraid I won't be of great help because I'm not to much into the Qt internals. But if I make progress I'll post here and of course I'd appreciate any kind of help.

Cheers, Robert. My colleague has solved this temporarily by putting the image painting logic outside the main project into a standalone executable, which is called with a set of parameters when ever there is the need to repaint one of the pictures.

The executable takes the parameters and outputs a picture file without user interaction, that is loads the GUI libraries but doesn't create any sort of GUI. Depending on your needs and configuration, this may or may not bring too much of an overhead (to my understanding the main problem is on the OS handling the shared library of QtGui4.dll in our case), but at least as a quick patch it has worked for us. I'll keep you and others posted via this forum thread if we find the way (and the time, off course) to push this thing forward - maybe we can come up with a solution together. I'm in the same boat. I'm happy to put some time into this if I can get some technical guidance. The only thing I have to contribute so far is that I read that QWidgets must be in the main GUI event loop thread and because they aren't 'reentrant' It sounds like it would require large modifications of the QCustomPlot library to remove it's dependence on QWidgets. That probably won't work.

What if we have a separate GUI loop running within the main window. Can we have it share the same screenspace as the main GUI window but be running on another thread? This might have the same effect as starting another QApplication like Robert said.

The GUIs don't have to interact, at least in my case, which might prevent multithreadding errors and make it simpler to implement. At a minimum, signal and slot communication would be nice. This thread has over 500 views! Let's put our heads together and figure this out!

Yes please let me know if i am doing something wrong, i find this behavor strange. Im plotting 4096 histograms, 4096x4096 sized heatmap and two line items. Not very heavy.

I have to call four replots for four channels using a for loop inside a slot which is called every 500ms by a QTimer. The histogram data is generated in a device that is connected to the PC via ethernet and sends the whole distribution in one go. Hence i have no option but to use setData. The heatmap is edited ( data()) to append the map. I donot have antialiasing or alpha.

The first call to replot, before i made the changes, takes about 600ms, the next one about 80ms. Do not know why.

This is just the replot, not the data processing, i.e. The total process takes up quite a bit of time. I activated opengl today, i use OGLWidget in QT5. And #define QT_GRAPHICSSYSTEM opengl and #define QCUSTOMPLOT_USE_OPENGL. With this, the first replot takes 400ms, and the subsequent ones take 50ms. This is a better. But if you could tell me why the first replot takes 400ms, that would be awesome, than i could trim down the use of threads.

With the modified code and ogl, it takes 150ms on the first replot and 1-2ms on the subsequent ones.

QT Repaint/Redraw/ Update/Do Something - Stack Overflow I'm New to QT. I understand that you can force a display refresh, but I've pulled all my hair out trying to figure out how. Here is what I'm specifically trying to do.

C++ - How to determine the correct size of a QTableWidget. The thread How to set a precise size of QTableWidget to prevent from having scroll bars? Qt-interest Archive, June 2007 between Lingfa Yang and Susan Macchia seems. Qt update ui from different thread Build instructions. Visual C++ 2010 contains all necessary SDKs for Qt compilation. However if you plan to use Qt with Phonon you need to install DirectX SDK first. The GUI Toolkit, Framework Page - Free Software A comprehensive reference on GUI toolkits, user interface frameworks, software libraries, class libraries,windowing APIs, and related software tools for GUI.

Qt update ui from different thread Adopted 10.10 UI. Support HTTPS streaming. Fgtech V53 Crackle. Add Partial Update mechanism to update player core only.

Sync up to the latest mplayer/FFmpeg source. Fix several issues on. Symbian - Wikipedia Nokia currently recommends that developers use Qt Quick with QML, the new high-level declarative UI and scripting framework for creating visually rich touchscreen. Qt update ui from different thread Droidin' out - Connecting android to the pc over usb Qt update ui from different thread Fluffypillow It looks interesting. Is Grid View the only option or can you do a normal gamelist like current ES? How does the grid handle different box sizes eg if. After Effects CC 2017; Multiprocessing?

Adobe Community I haven't updated to CC 2017 yet, but it sounds as if they've made significant performance improvements to the render engine since CC 2015. Considering News - qBittorrent Official Website News Friday December 1st 2017 - qBittorrent v4.0.2 release. This is a hotfix release too. It addresses some important RSS issues. MacOS builds will follow. Qt update ui from different thread May 11, 2013. Now to get onto the specifics of your question, you're not able to directly modify the ui elements of your main GUI thread from a separate thread.

You have to connect a signal from your 2nd thread to a slot in your main thread. You can pass any data that you need through this signal/slot connection but you're. Qt update ui from different thread Jul 14, 2010.

My application runs heavy mathematical equations based on input files. The actual work is done within a separate thread. This way the GUI remains responsive. Everything works great, but I just can't figure out how to update the GUI from the separate thread. While processing the equations I want the GUI to. Qt update ui from different thread This thread is called the 'main thread' also known as the 'GUI thread' in Qt applications. There is a shared copy of the code and a separate stack for each thread.

Sometimes it is necessary to access one object from different threads; for example, when objects living in different threads need to communicate. Qt update ui from different thread It looks like your RandWalk thread isn't actually running. You are calling generateCoordinates from the GUI thread, so it's holding up the program there. That explains why you only see the last update. The QThread documentation shows a couple different ways to do work in another thread Qt update ui from different thread Hi, I am new to qt programming. I want to update my UI from worker thread. In my worker thread i add code to read accelerometer reading as i get my reading i want to update my UI according to reading i get from accelerometer.

How can i call GUI method from worker thread. I make a subclass of QThread.