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@SGaist Thank You. This helps and this is what I was searching for.

@Taytoo Help me the solution to build QT Static for window support qgif ?

Can you try using Wayland -> Wayfire in sudo raspi-config?

Thank you!
I'll take a look and report back

@SimonSchroeder said in How to create a toolbar like in Qt Creator?:

The tool bar you are showing has a QComboBox (this is just adding any widget to the toolbar which is possible). Next to that are most likely QToolButtons. These can also be changed to have a toggle state or a drop down menu. Tool buttons are especially designed to be used inside tool bars. They have a picture/symbol but usually no text.

Thank you!

Hi @ShahShaj,

While I completely agree with everything the others have said, just for fun (and to answer the original topic question) I've tried installing Qt on Ubuntu 20.04 on GitHub Actions, via install-qt-action, which in turn uses aqtinstall - a Python-based application that installs Qt from the same public mirrors as the Qt Online Installer.

For my project, the result is aqtinstall successfully installs Qt 6.2 through to 6.9 on (GitHub-modified) Ubuntu 20.04.06 LTS. Note, that "GitHub modified" bit might be important - I'm not sure how much customisation GitHub does to their Ubuntu images, but you can see their customisations for yourself at https://github.com/actions/runner-images

(Also note, I didn't try installing Qt 6.0 or 6.1, just because I did this on a temporary branch of a project that uses Bluetooth, and Qt didn't add BLE support to the Qt 6 branch until 6.2)

Now, once installed, the open source project I tried this on, managed to build and pass all unit tests quite happily using gcc, but not using clang. However, it appears that the clang failures might be because of some very-modern code coverage support my project enables, so clang might work just fine if I disabled coverage reporting, but doing so was a step too far for me to both with this experiment :D

So, my hypothesis is that:

installing Qt 6.x on Ubuntu 20.04 should be possible via aqtinstall. possibly requiring some prerequisites first though (such as some system libraries, Python, etc being installed and/or upgraded) possibly only for gcc (clang may or may not work; didn't work initially for me)

You can see which builds passed (ie the gcc ones) and which failed (ie the clang ones) here: https://github.com/pcolby/dokit/actions/runs/14154258108

You can see the modified GitHub workflow file I used here: https://github.com/pcolby/dokit/actions/runs/14154258108/workflow

You can see the aqtinstall commands that did the actual Qt installation by looking at the log output of the "Install online Qt version" steps, for example:

python3 -m aqt install-qt linux desktop 6.9.0 --autodesktop --outputdir /home/runner/work/dokit/Qt --modules qtconnectivity

Finally, let me reiterate what others have said: absolutely try to upgrade your OS if you can (I know nothing about nVidia's Deepstream). But if you can't, then give aqtinstall a go. I'm sure it won't be easy, but should be possible...

Good luck :)

Hi @nga_tom,

As per the docs:

Apple platforms

Each permission you request must be accompanied by a so called usage description string in the application's Info.plist file, describing why the application needs to access the given permission.

<key>NSMicrophoneUsageDescription</key> <string>The microphone is used to record voice memos.</string>

Here's a complete example from one of my open source Qt projects: https://github.com/pcolby/dokit/blob/e734041b06e48d7aaf577bafa86359d05e001d05/src/cli/Info.plist.in#L27

You basically want to drop an Info.plist file that includes a NSBluetoothAlwaysUsageDescription key/value, into your application binary's directory.

You could also search the qtconnectivity repo for Info.plist to see some other examples, such as this one for the btscanner example: https://github.com/qt/qtconnectivity/blob/6f114cfd71ff970c6244d89e2d79f15c4229b2c6/tests/manual/examples/btscanner/Info.plist

Cheers.

One data point about Apple's preference: Safari's Bookmarks menu uses a "globe" icon for pages that lack their own icon, and that monochrome globe icon does switch between light and dark when selected.

@paulmasri hi, thanks for sharing your knowledge with us

@Christian-Ehrlicher said in QFileSystemModel::setRootPath behavior does not match documentation under Windows:

I don't understand - when you set C:\ as the root path why/how to you see the contents of D:\ ?

I think you are confusing QFileSystemModel::setRootPath and QTreeView::setRootIndex

Thanks for reply. I run:
qt-cmake with -DCMAKE_BUILD_TYPE=Release parameter. Now my C:\mysql-8.0.28-winx64\build-sqldrivers\plugins\sqldrivers directory looks much better:

7658df53-1a08-4851-991c-417bbe8ba871-image.png

I can see qsqlmysql.dll.

I added to my project. It works perfect!

Thank you very much for help and for you patience!

Have a good day :]

before moveToThread, QModbusRtuSerialMaster had been created in main thread, and its in a deffrent thread

@Pl45m4 said in When to use signals and slots, versus direct function calls, from parent to child?:

I've never seen this before in working code. Proof please ;-)

#ifndef SIGNALTEST_H #define SIGNALTEST_H #include <QObject> class SignalTest : public QObject { Q_OBJECT public: explicit SignalTest(QObject *parent = nullptr); public slots: int intSlot() { return 123456; } signals: int intSignal(); }; #endif // SIGNALTEST_H SignalTest *obj = new SignalTest; QObject::connect(obj, &SignalTest::intSignal, obj, &SignalTest::intSlot, Qt::DirectConnection); qDebug() << /*emit*/ obj->intSignal();

We do indeed get 123456 printed as return value from signal call, as per @GrecKo.

I do not think any of the (documented, at least) signals used by Qt have a return value, but it does work. Of course, if I change to Qt::QueuedConnection it does not work, I get 0 back.

Googling, even @SGaist wrote in https://forum.qt.io/post/596362

Signals have no return value.

And in the "other" forum someone wrote in https://www.qtcentre.org/threads/70910-How-to-get-the-return-value-when-signal-emit?p=307681#post307681

All signals and slots have a "void" return value. You cannot return anything that way.

But over at stackoverflow the accepted answer at https://stackoverflow.com/a/5903082/489865 shows same as mine but with a QString return and discusses it a bit further.

So it seems this is a little known "feature". I do not see the Qt docs saying anything about this, neither that signals should be void nor what happens if they return a value.

@Christian-Ehrlicher Correct same is the case with me. For me also MySQL Connector C 6.1 lib path was present in PATH env variable. I changed it to MySql server lib and it is working now. Thank you