qtbase | Dynamic bindings from R to the Qt library | Build Tool library

When I put Qt widgets in a QHBoxLayout layout using QT Designer, there seems to be a minimum width for QLineEdit widgets of 17 x's, at least if this is the current source code:

https://github.com/qt/qtbase/blob/dev/src/widgets/widgets/qlineedit.cpp

I cannot find a way to make PyQt5 lay those widgets out so they will be narrower than this default, but still change size if the font is changed.

As an example, a QComboBox will be automatically laid out so that it is just wide enough to display the longest text that is entered as a possible value. If the longest text entered for a combobox in Designer is 5 characters, the combobox will be laid out as quite narrow compared to the minimum QLineEdit width. How can I configure a QLineEdit with a number of characters so that it is always wide enough for that many characters, whatever the font is set to, and no wider, using just QT Designer? I know in Designer I can enter maxLength, which will limit the maximum number of characters that can be entered/displayed, but that setting of course has no effect on the layout.

I have some text boxes that will never have more than 5 characters in them, for example, and the layout with Designer makes them at least 3 times wider than I will ever need. This is using the default "Expanding" horizontal policy, but I have tried many combinations of horizontal policy and values for minimum size or base size. I want to allow for people to have different font sizes, so I cannot safely set a maximum pixel size and I cannot safely set a fixed horizontal size. The handling for QComboBoxes is precisely what I want for QLineEdits.

This is all in python using the latest versions of PyQt5 available on Pip, pyqt5 5.15.6 and pyqt5-qt5 5.15.2.

I am trying to add a qt widgets application/project to my yocto image and compile it through it. I know that I have to add a custom layer and make a recipe which has reference to the files of the qt application. I have also inherited qmake5 and inserted DEPENDS += "qtbase", but I am confused about which files to refer through SRC_UI in my recipe. The QT application file is a bare bone project called "hi" which contains no additional code and pops up a plain helloworld window. The project file contains following files:

I'm trying to unpack .tar.gz file to my root during the building system, but it doesn't work because of an unclear reason for me. I did it in the same way as other recipes in my meta (which works fine), but in this case, I have an empty directory in the target system root. The recipe has the same name as tar.gz.

Based on Yocto Project Documentation and my other experience it should work fine. I tried to remove manually tmp, sstate-cache directories and rebuild system, but it doesn't change anything. The recipe is building, but the /my-app is empty. Can I force extract my archive?

Tree file:

I want to change Kernel configuration.

I have my own layer created and inside my layer I have a _%.bbappend file which directly targets the recipe linux-ti-staging.bb (link). This recipe builds my kernel:

I am using Qt 5.7 (C++) and want to add custom functionality like a reset option to a QSpinBox (as well as QDoubleSpinBox and maybe some other input widgets). This functionality should be accessible via the context menu. However I do not want to replace the default context menu. Instead I want to add my custom actions on top or below the already existing actions.

I found almost matching answers to this question:

• https://forum.qt.io/topic/81946/add-item-to-top-of-standard-context-menu-at-right-click
• How to add an entry to toolbar context menu in qt?

However, these do not help in my case since it relies on the Widget to have a method that creates and returns the standard context menu (like QLineEdit::createStandardContextMenu()). The spin boxes do not have such a method.

I also tried to go the cheap way and copy the code that creates the default options directly from source (https://github.com/qt/qtbase/blob/5.7/src/widgets/widgets/qabstractspinbox.cpp line 1249). This is also not really satisfactory since it uses private members of the underlying line edit.

Is there a (standard) way to reuse and augment the default context menu of a Q(Double)SpinBox or any QWidget in general? Or do I have to manually re-implement the default behavior?

I have a really simple Qt (QML) project :

CMakeLists.txt :

In a QSpinBox, when the range is sufficient, the user is allowed to enter thousand separators.
Eg: 1.2.3.4 is a valid entry, en then fixup() just removes the dots. Resulting in 1234.

How can I prevent the user from entering thousand separators?

Previously I made something similar based on QLineEdit which uses validators.
But QAbstractSpinbox doesn't use QValidators. So I'm not sure how to proceed.

I've been trying to build Qt 6.2.2 from source. I downloaded the sources package from the online installer but it fails each time, each time with a different error. I've tried a variety of configurations such as:

For a project which uses MQTT, I always had to compile the QtMqtt module from source, because it wasn't included in the prebuilt windows release and couldn't be chosen for installation either. In Qt5 that was pretty easy: Download source code from official git (https://code.qt.io/cgit/qt/qtmqtt.git/), open the .pro file in QtCreator and compile the project. For installation, I just moved the .dll files to my Qt install directory.

Now in Qt6, the build process was switched from qmake to cmake, so I cannot simply load the project in QtCreator, but have to compile it manually using CMake, which I find really unintuitive and prone to errors. From what I understand, I cannot compile single modules on their own from now on, but have to get the whole Qt 6.2.0 source code instead (i.e. via installer option) and then use a --target option on CMake to build only specific module. So here is what I did so far:

1. Get Qt source code from installer (installed to Qt/6.2.0/Src)
2. Create a command line environment according to this manual
3. Open cmd environment, navigate to build folder (i.e. Qt/6.2.0/build)
4. Configure build using command: ..\Src\configure -prefix Qt\6.2.0\build
5. Build with cmake using command cmake --build . --target qtmqtt
6. Install using command cmake --install .

What happens, is that the configuration works, and the build supposedly too, but installation fails with something like: