QVTKWidget is transparent - qt

I am just a beginner in both Qt and PCL. I am trying to display PCL viewer in the main Qt GUI Window. When I use PCL viewer, it shows up in the separate window. I also try with QVTKWidget.The problem is that when I run the program, the QVTKWidget become transparent and cannot load point cloud. I run in Ubuntu 18.04 , Qt 5.9.5, PCL 1.8, Vtk 6.3. Please give me some advice.

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Dark mode in standalone Qt Designer on Windows?

I'm developing one GUI app (among others) in Python with PySide2 and my main editor is VSCode and I'd like to keep it this way - I'm using the standalone Qt Designer for GUI layout calling it from VSCode when necessary.
I see that the full Qt Creator has a way to select couple of different dark modes in its IDE settings, however I see no such possibility in the Qt Designer launched as standalone application.
I develop on Windows 10 by the way and setting its dark mode doesn't change how Qt Designer looks, it keeps its Windows Vista look:).
Is there something that can be done, maybe a command line parameter?

Qt Qml and tensorflow build using Bazel

Currently I am working on a project that includes Qt Qml and tensorflow. I got the method to build Qt widget application but I could not find out how to build Qt Qml using Bazel.. Pls help on this.
Which platform are you targetting?
I worked in a project integrating Tensorflow with Qt/QML for Linux, iOS and android. One option is to compile Tensorflow with make for each platforms. Details about how to do this with an example app are given in this post.
https://mechatronicsblog.com/machine-learning-on-desktop-ios-and-android-with-tensorflow-qt-and-v-play/

How to debug/step into QT SDK sources from my project

I want to debug, set break points etc in QT SDK sources,
I have QT5.5.0 built with symbols and symbols are picked up, at lest GDB says so.
But I still cannot debug into for Example QGuiApplication, well I don't really care about QGuiApplication but I want to be able to set break point anywhere in QT Sources and stop there when my code get there.
I do have QT 5.5.0 project opened alongside with my project, but setting break point in QT5.5.0 does not have any effect, also stepping into any QT SDK code simply does nothing, it just stays where it was stopped by breakpoint in my project.
So question is how can I place breakpoints in QT SDK code anywhere I want and when I debug my project I will be able to stop in QT code. And how can I step into QT SDK code.
Ubuntu 14.04, QT 5.5.0, Creator 3.6.0, QNX ( ARM platform ) but it is irrelevant.
Don't install any QT binary (qtcore/qtgui),
build from source and
intall them with debug symbols, should be around 200~300M each library.
Make sure your example code is loading the debug version of qt files.

Is Qt Creator built with Qt Creator?

Questions:
Is Qt Creator built with Qt Creator?
Similarly, is Qt Designer built with Qt Designer?
BTW, why are there two Qt IDEs? Are they competitors? Which one should I use? I am using Creator.
What is Qt SDK? I am asking this because the Qt Designer & Creator 2.2.1 and Qtmake 4.7.4 that I installed thro ubuntu 11.10 s/w centre does not work. The build menu is all greyed out.
When I downloaded the latest QtSDK (2.3.1/4.7.4) into a separate installation into /opt/QtSDK, both the ubuntu sanctioned installation and the /opt/QtSDK would work as expected.
Why did my ubuntu sanctioned installation not work without the SDK? What does the SDK do?
This one is for Ubuntu enthusiasts - Qt IDE requires the SDK to work, and yet ubuntu released both Creator/Designer without checking if they work first? There is no QtSDK installation item in s/w centre. Is that intentional, or a procedural bug?
After I build my desktop app (I am building a tabbed file explorer) on Linux, what steps do I need to make to have it running on Windows 7/Vista? Will I rebuild on a windows version of Qt Creator?
I also notice that Qt Creator code generation is not perfect. It would forget to include some Qt library files in the auto-generated code, and I had to correct that manually.
Is Qt Creator built with Qt Creator?
I believe so.
That doesn't mean that everyone who works on Qt has to use it - just that I believe that lots of people do.
I don't work for any of the companies that have produced Qt, but my reasoning is:
A Google search for "dogfooding qt creator" brings up plenty of hits, including this comment from November 2010:
We’re also “dogfooding” by releasing complex apps like Qt Creator and the Ovi Suite on the desktop ports of Qt
They've put a massive amount of effort into Qt Creator over the last few years. It's hard to imagine that being worthwhile, unless they used it themselves
At recent Qt Developer Days, Qt Developers have spoken really enthusiastically about Qt Creator
Similarly, is Qt Designer built with Qt Designer?
Yes. A look at the Qt Designer source code shows plenty of .ui (Designer) files.
Why are there two Qt IDEs? Are they competitors? Which one should I use? I am using Creator.
When you edit .ui files insiide Qt Creator, you are still running Qt Designer: it's simply showing the Designer window inside Creator, for convenience.
What is Qt SDK? ... What does the SDK do?
Qt SDK is just a convenient way to download all the Qt tools in one go. You don't have to use it.
This one is for Ubuntu enthusiasts ... Is that intentional, or a procedural bug?
Sorry - no idea. It's hard to imagine it being intentional though.
After I build my desktop app (I am building a tabbed file explorer) on Linux, what steps do I need to make to have it running on Windows 7/Vista? Will I rebuild on a windows version of Qt Creator?
You will need to install Qt on a Windows PC, and then build your source code in it.
You can either do that by using Qt Creator and the Windows compiler it includes (mingw) or you can use another compiler, if you have one, e.g. Visual Studio.
I also notice that Qt Creator code generation is not perfect. It would forget to include some Qt library files in the auto-generated code, and I had to correct that manually.
If you've used any non-Qt classes in arguments to signals and slots, then this answer may help you there.

is there a way to run QML Viewer for desktop that will show Qt Quick components on Meego Hamattan?

I tried to run a Meego Hamattan Qt Quick project with Qt Quick components for Meego Hamattan that targets my desktop(Windows) and it only appears as all white.
I would like to be able to run Meego Hamattan UI in desktop, so that I wouldn't need to use QEmu(which is sluggish) to test my UI.
Please Answer my burning question! =)
Thank you very much!
I assume your only choice is QEMU or a real device.
The QML meego components use platform code that is not available/compiled on your desktop.
I think the problem is not with the components.. Is there are some errors in the QML code, the screen would be blank.. Look at the space below the workspace where compilation errors, build errors and application output will be notified.. If you note some text in Red color then its your mistake.. I can test my Qt quick and QML projects in Desktop build, Simulator build and also using QML viewer.. So the problem will not be the one you are mentioning..

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