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Qt Development

Everything development. From desktop and mobile to cloud. Games, tools, 3rd party libraries. Everything.
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  • This is where all the desktop OS and general Qt questions belong.
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    D
    I don't argue that it may work on this simplest two-column example without any issues but that's not my case. My SQL query is a bit more sophisticated and includes JOINs as well as calculated columns (with MAX, DATEDIFF etc). Checking with bare SQL request via mariadb command line client or phpMyAdmin console shows that the query line itself is ok - I get all expected rows and columns. And as it shown on the screenshots above the problem goes away if I wrap DATE-typed columns with DATE_FORMAT so I effectively get string objects instead of date. So that's why I've decided it's a bug somewhere in Qt. I've also prepared minimal database sample which exposes erratic behavior. Moreover, the database itself may be provided by third-party service and not by means of Qt-aided creation. Who knows - may be there are some difference in a way database were prepared.

  • The forum for developing everything embedded: Linux, WinCE, Symbian, MeeGo... you name it.
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    T
    The same in android-Qt6.9.3. It worked in android-Qt5.15. Context: App runs in Kiosk mode. Short power button click shall not stop the app but only switches off the screen.

  • Looking for The Bling Thing(tm)? Post here!
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    R
    Hi, Using the following palette on MacOS Tahoe 26.1: SystemPalette { id: palette colorGroup: SystemPalette.Active } On 6.9.x, using the code for the bottom chatbox input: Rectangle { id: inputBox anchors.fill: parent color: palette.window radius: 12 border.color: palette.midlight border.width: 1 // TextArea content TextArea { id: promptField anchors.fill: parent anchors.margins: 8 background: null color: palette.text wrapMode: TextArea.Wrap placeholderText: "e.g., Find Python devs in Germany with 3+ years" padding: 8 rightPadding: sendBtn.width + 16 Keys.onReturnPressed: function(event) { if (!event.isAutoRepeat && (event.modifiers & Qt.ShiftModifier) === 0) { sendBtn.clicked() event.accepted = true } } } // Send button inside the TextArea Button { id: sendBtn text: "⏎" anchors.right: parent.right anchors.bottom: parent.bottom anchors.margins: 8 width: 45 height: 37 font.pixelSize: 18 } } I would get something like: [image: c8af108f-378a-4ecc-9095-ef5ffba37e2a.png] But with the same code now built with 6.10, I get: [image: 7b4c17b5-c03f-46de-a07e-07b915d8ceee.png] Why are now all palette colors white? where are the shades of gray in the system theme?

  • This is a discussion space for

    • for audio / video playback and recording
    • media formats and codecs
    • camera and screen sharing functionality
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    47 Topics
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    SGaistS
    You can run ldd on your libreoffice binary to see which libraries are linked. To enable logging categories, you have the different options describe in the documentation.

  • Have a question about Qt Creator, our cross-platform IDE, or any of the other tools? Ask here!
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    V
    Hi Thanks For your answer, It's Qt Creator, i use an external terminal. I used the Debbuger Log, but it closes when I close the application. Attached is the random error message that appears when I stop the application in debug mode and want to restart it. Thanks, VIncent [image: a29919e9-237b-470c-9f4e-1f3901ab9628.PNG]

  • Your Qt just doesn't want to build? Your compiler can't find the libs? Here's where you find comfort and understanding. And help.
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    Axel SpoerlA
    Also not a lawyer here. Your obligation is to comply with LGPL. That means your app has to be linked dynamically to Qt (not static) you have to include a license note saying explicitly that you are using Qt under LGPL users must be able to replace the Qt version with another, without any restrictions (no hardware / software tricks to put a stick in the wheel).

  • What can we say - we like games. And you can use Qt to write some. Questions? Ask here.
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    8Observer88
    Debug drawer for Box2D v3 using QPainter It uses b2World_Draw to draw Box2D objects for debugging. You can just download and run it without compiling libs because it include libs for Windows (MinGW) and Android. Source: https://github.com/8Observer8/debug-drawer-qpainter-box2dv3-qt6-cpp [image: 2a9af153-b7d2-40a0-9702-5fdfb79ccf52.png]

  • Discussions and questions on QtWebEngine
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    @Axel-Spoerl “Thank you for the update. I’ll retry accessing the repositories and continue monitoring the situation. Please let me know if there are further changes.”

  • You're using Qt with other languages than C++, eh? Post here!
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    N
    Indeed, it didn't work for PySide2; I had to implement a workaround. The option is present in the shiboken6 documentation, but not in shiboken2. I conclude it is not supported by the latter. Thanks

  • Combining Qt with 3rd party libraries or components? Ask here!
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    JonBJ
    @Buller You are aware that both of these are compile-time macros (e.g. https://qwt.sourceforge.io/qwt__global_8h_source.html) so, assuming you put these in your source code, they do not necessarily tell you anything about the "runtime versions" that the libraries might have been compiled with in the past? Or the runtime version of either Qt or QWT which might happen to be found?

  • For discussion and questions about Qt for Python (PySide & Shiboken)

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    T
    @JonB Unfortunately trying to seek or get the size doesn't work, as the open command fails. QFileInfo.size() returns 0 for one file, and -1 for another. It returns the correct size on the smaller JSON file. On Linux the correct size is returned for all of the files. Right now I am indeed doing the workaround of having the file outside of resources, but it's strange that it would be doing this and I'd like to figure out why :) @Christian-Ehrlicher I enabled binary transfer using a .gitattributes and ensured that the file was changed and committed, and pulled. Nothing changed. Both files have the same md5sum and are around 12 megabytes. I'm stuck. I'll try in the next day or two to see if I can make a MRE. Thanks for the suggestions!

  • Specific issues when using Qt for WebAssembly

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    F
    I'm trying to use JavaScript with promises using the JSPI option. I created a test project like this: #include <QGuiApplication> #include <QQmlApplicationEngine> #include <QQmlContext> #include <QObject> #include <cstdio> #include <iostream> #ifdef __EMSCRIPTEN__ #include <emscripten.h> #endif using namespace std; EM_ASYNC_JS(int, do_fetch, (), { out("waiting for a fetch"); const response = await fetch("vtkqml.html"); out("got the fetch response"); return 42; }); class ButtonHandler : public QObject { Q_OBJECT public: ButtonHandler(QObject* parent = nullptr) : QObject(parent) { } public slots: void onButtonClicked() { cout << "Calling" << endl; do_fetch(); cout << "Returned from fetch" << endl; } }; QGuiApplication* g_app = nullptr; QQmlApplicationEngine* g_engine = nullptr; ButtonHandler* g_handler = nullptr; int main(int argc, char* argv[]) { g_app = new QGuiApplication(argc, argv); g_engine = new QQmlApplicationEngine(); g_handler = new ButtonHandler(); g_engine->rootContext()->setContextProperty("buttonHandler", g_handler); g_engine->loadFromModule("vtkqml", "Main"); cout << "Calling" << endl; do_fetch(); cout << "Returned from do_fetch" << endl; if (g_engine->rootObjects().isEmpty()) { return -1; } return 0; } You can see that I call the EM_ASYNC_JS function first in main and then in a slot. As a result, I get the following output: Calling waiting for a fetch got the fetch response Returned from do_fetch Calling Uncaught Error: undefined It seems that the call only works when it's made from the main function, and I don't understand why. Does anyone have an idea what might be causing this?

  • Discussions and questions about Qt Quick Ultralite and using Qt on microcontrollers in general

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    J
    Hello everyone, I'm following the guide from https://doc.qt.io/QtForMCUs-2.10/qtul-nxp-rt1170-qsg.html to develop on the NXP i.MX RT1170 platform. I carefully followed each step in the tutorial, but when I reached the final build stage, the compiler reported the following error: make[1]: *** No rule to make target 'libQulCore_cortex-m7-hf-fpv5-d16_Windows_armgcc_MinSizeRel.a', needed by 'MIMXRT1176_Project.axf'. Stop.  I tried going back through the tutorial to check if I missed anything, but I couldn't identify the problem. Could anyone advise how to resolve this error? Environment: IDE: MCUXpresso IDE v11.9.0 [Build 2144] [2024-01-05] SDK: SDK_2_16_0_MIMXRT1170-EVKB Qt for MCUs: 2.10.1 Thank you!

  • The forum for discussing the Qt Digital Advertising Platform

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    @nayka Can I use QtDigitalAdvertising on PC applications? Or is it only allowed for use on Android or iOS mobile devices?

  • For discussion and questions about Qt Insight

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    jsulmJ
    @Alejandro_qt_ Here is an example how to build qtbase module: https://stackoverflow.com/questions/50022325/building-qt-module-from-source