@mpergand Awesome! I didn't know you can catch these. Thanks for your explanation.

@jsulm there was in fact a problem with window3d() that MinGW didnt complain about! Thanks!
@JonB no I had commented out only up to the second screenshot, so that's why this was the problem.
And about the second issue, to be honest I adapted the constructor from an older version of the application and it also had &argc. At one point I also noticed it and now I tried out both and both work.

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.

@Petin, does your program run correctly if you don't throw an exception?

Forgive me if this doesn't help, but it's what I'm thinking.

I'm not sure if this will even work (unsure if you can swap sources) like this on width changed... but onCompleted should be ok?

It may get you experimenting / thinking differently to get a solution.

http://doc.qt.io/qt-5/qml-qtquick-loader.html#source-prop

Loader { id: container anchors.fill: parent // setSource on Loader Component complete Component.onCompleted: { doSetSource(); } } Connection { target: container; onWidthChanged: { doSetSource(); } } function doSetSource(){ if(container.width < 320) { container.setSource("ViewSmall.qml"); ...

@kshegunov ,

agree with what you have written.

I think , I was in rush to reply to the one who objected on using the pointer to a container structure.

So I went on and hoping to convey the idea of me doing it rather than being careful in writing the correct way.

All the best to you Kshegunov.

Indeed, don't forget to provide a minimal compilable example. That will help greatly.

@ChrisW67

Thank you for you help.
Probably the thing is, QSerialPort has a problem to work in a new thread.

I can handle the other QObject in a new thread very well, and the exception only happens when the Object contains QSerialPort.
Also, in my last post, I actually never user QList, although Qt tells me something wrong with QList.

I have given up on working serialThread. QSerialPort does work good in the main thread.