General and Desktop

@JonB @Smeeth asked the question on SO, and I found setting the stylesheet on the parentWidget worked. He asked why and I couldn't answer, hence turning to this forum

No but thanks! Will give it a try :)

A quick search with the "Qt Creator debugging" keywords would have given you Qt Creator's documentation on how to setup for debugging as well as this VoidRealms video on the subject on youtube.

In that case, you should check the bug report system to see if there's anything related. If not, then please consider creating a new report providing your example as well as your complete system specification. By the way, what graphics card are you using ?

Can you test whether a more recent version of Qt still has that problem ? The Qt 5.9 series is at the 5.9.6 and 5.11.1 being the current version.

I did forget the install, it has been a while since I did this:) Why not the precompiled source? Good question, all I know is that I have always compiled the source myself and old habits are hard to break;)

O dear I did mess it up ! Blah silly me! Will give it a go thanks so much!

@JonB As you told, it is close() problem. i did it as given in qt examples. It is working now. Thanks to ALL forum members.

@JohanSolo Yeah, but I think (for Qt) we still have to support MinGW and whatever on MacOS and ... Unlike the functions for swapping 16 or 32 bytes, I couldn't find standard ones for 64 bytes anywhere when I searched. Shame!

@jsulm I have added QT += network as a seperate line in the .pro file and it now works :) Thank you so much

@SGaist Thanks a lot, I'll post my question there.

@Marek Well Qt is only a library providing "abstracted, convenience" functions where possible, it's not magic, so yes sometimes you have to supply your own alternatives as best you can. If you can't find anything, chances are nor can Qt.

@raven-worx Thanks for all the help!

There's always a need to return something when your method has a return type. If you don't know what to return at first then return a default value. Also, always take into account the warnings the compiler throws at you (there is one for functions not returning anything when their signature contains a return type). As the old saying goes: a compiler warning ignored today is a catastrophic crash in production tomorrow.

@GCDX Further to @SGaist 's observation. Although http://doc.qt.io/qt-5/qsettings.html#details states Constructing and destroying a QSettings object is very fast. to me it seems "odd/inefficient" to be creating one specifying your organization & project names each time, as these never vary. I would either take the doc's suggestion of: If you use QSettings from many places in your application, you might want to specify the organization name and the application name using QCoreApplication::setOrganizationName() and QCoreApplication::setApplicationName(), and then use the default QSettings constructor or I would create one & only one QSettings in your app and re-use that each time.

Thank you.... I read document not careful enough ,My mistake.....

@VRonin I got it ,thanks

@udayraj123 said in qtmqtt make error on linux: "qmqttglobal.h: No such file or directory": Download zip from https://github.com/qt/qtmqtt I can confirm that using the .zip download from such location gave me same errors as you mention (I'm using Lubuntu 18.04 / Qt 5.11) However cloning https://code.qt.io/qt/qtmqtt.git and doing: qmake -r qmake make sudo make install led to QtMQTT module built Ok and installed along other existing modules in my Qt installation so later on you could use the module in any application (i.e. provided examples or your own).

@kottalovag I had the same problem and was able to verify that the change from raw pointer to std::unique_ptr broke it. Thanks for the tip, you are a life saver. In other words, if you have "std::unique_ptr<Ui::MainWindow> ui;" in your mainwindow.h, your project will still build and run, but you won't be able to use "go to slot" from the ui designer. To fix, change it back to "Ui::MainWindow* ui;".