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@SGaist said in Is there possible to make and test qt program online ?: JupyterHub no just like online GDB for c

Yes I noticed already that there are bug reports for qt 6.2 and macOS 12. As you said the scanning is working outside if you the add the key in the Info.plist. This works for starting the scanning but it does not find any Low Energy Devices. Or could you scan for Low energy devices at all?

https://www.qt.io/blog/2012/09/28/qt-support-weekly-27-widgets-on-a-header

@JonB With some experimentation, I got the desired result.

a swift (hehe) google search resulted in this so topic https://stackoverflow.com/a/52406553/15422846 its objective c, so you should be able to include it in your c++ project

@Thank-You I've shared my solution and marked it as the best answer. Thanks.. :)

@SocketSackett Continuing ... I found the suggestion on Stack Overflow to use: db = QSqlDatabase(); db.removeDatabase(cnxn); after the close was a way to fix the duplicate connection close error. This is wrong. Doing this will not allow the work done to be updated. I removed that, & did a straight DB close, & it is updating once again. Checking for pre-existence of DB path with the QSqlDatabase::database.isValid() will suffice & is a good approach.

AH I FIGURED IT OUT. So for whatever reason, since i was creating a new QGroupBox pieGroup every time the function was called that somehow prevented the title from updating. So I changed it to create the new groupbox on the first click only. Now all the other clicks just update the title. I don't know what's going on under the covers. but it works now.

@raven-worx Not at all sure what I did wrong before (it's been a while), but did just what I would have expected it to do. Problem solved

Hi, If you declare slots, you need to have them implemented even if the method is empty.

@Dariusz said in cmake automoc + dll... error LNK2001: unresolved external symbol "public: static struct QMetaObject: Do I have to write some kind of post build command that copies all moc files to some location & ship it with my dll/include folder? no, the moc data is compiled into your binary, like any other class/method etc. Since you are using cmake, did you set the AUTOMOC property?! https://doc.qt.io/qt-6/cmake-get-started.html

Qt has support for pkg-config both to use it to link to libraries as well as for the lib template. From the looks of it, on Debian, there are .pc files available for the various Qt modules.

Try it in designer which has preview ==>Form==>Preview in==>Fusion Style to make sure the layouts are right and then generate your C++ code.

@feistykittykat Thank you very much! That worked for me as well. Was driving me nuts that it used to work when I was doing 5.x development and since going to 6.2.1 I have found a lot of gotchas in my code!

Compiled Qt statically with -static-runtime enabled, and now the slowdown is gone. Maybe finding libstdc++ and libgcc was slow. I'll still need to do some more testing, but Im positive that this was the problem

Yup. You can find the packages under Pi Menu > Preferences > Add/Remove Software. Doing a search there will eventually bring up the needed modules. I am still curious as how one builds the modules separately though. Thanks again!

@Swati777999 said in Functions of QWidgets used for QTableWidgets: QTableWidgets class is a subclass of QtWidgets. The functions of QWidgets can be used for QTableWidgets objects. Yup. I have found some functions not working in my program. Like what? Yes you can call methods of QWidget on, say, QTableWidget. I have another doubt, can public slots be used as public member functions of a class? ? Yes, public slots are just public methods.

@sierdzio Thanks.

@pgiovanni said in Populating a vector of QPieSlices: QPieSlice it is derived from QObject. QObjects are NOT copyable! So, store pointers to QPieSlice in your vector.