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General and Desktop

This is where all the desktop OS and general Qt questions belong.
83.6k Topics 457.7k Posts
  • Qt Embedded: displaying on two screens using QGraphicsView and QGraphicsWidget

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    SGaistS
    I mean what backend are you using ? If not QWS, do you have an Xorg server running on your device ?
  • Qt setStyleSheet background-image crash on ubuntu 18.04

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    SGaistS
    Can you provide a minimal compilable example that shows the behaviour ?
  • Qt QLocalServer Message Mode Support

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    SGaistS
    Hi, From the looks of it, you would have to rebuild Qt yourself.
  • QLineEdit action's icon - active mode doesn't work

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    SGaistS
    Hi, Please provide a minimal compilable example that shows that behaviour. Also, you provided Qt Creator's information, not the Qt version you are currently using.
  • 0 Votes
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    SGaistS
    Rather than having both your PLCs competing to write in some global structure. You should rather have them independently fill each their own structure and have some sort off watchdog switching from one or the other if needed. Depending on the how often the PLC are supposed to send data, you should maybe consider restarting the network check when you receive data rather than having that again competing with incoming data.
  • How handle close tab event?

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    SGaistS
    You should rather use QTabWidget::widget and use the int parameter of the signal to get the widget that was requested to be closed. It might not be the one that's currently shown.
  • qxcbintegration cannot create platform opengl context neither glx nor egl are enabled

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    SGaistS
    Hi, What are the differences between your development machine and the other one ?
  • Multiple connections to in-memory QSqlDatabase

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    B
    Nevermind, I got it. To enable an URI database name, I also had to set the QSQLITE_OPEN_URI option. So calling setConnectOptions("QSQLITE_OPEN_URI;QSQLITE_ENABLE_SHARED_CACHE") and setDatabaseName("file::memory:") everything seems to behave as I hoped (at least in this minimal example). Thanks!
  • noobie - using WinPCap

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    C
    more searching.. I found an interesting tidbit to disable the X button: setWindowFlags(Qt::Window | Qt::WindowMinimizeButtonHint | Qt::WindowMaximizeButtonHint); and then I finally came across... in mainwindow.h I added in the close event public: explicit MainWindow(QWidget *parent = nullptr); ~MainWindow(); protected: void closeEvent(QCloseEvent *event); and in mainwindow.cpp I added void MainWindow::closeEvent(QCloseEvent *event) { capRunning = false; event->accept(); } So at least it does properly stop now. QT is quite the challenge to get used to. Thanks for the assistance and suggestions.
  • about QAbstractItemModel::beginInsertRows

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    dheerendraD
    You can move the issue to Solved also.
  • Modification to form are not reflected when running the application.

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    D
    @dheerendra I went to the root of my repo and issues: find . -iname 'ui_mainwindow.h' I found an older gui project I had created as training with the file and I deleted that folder. Other than that, I only have 1 other file with that name. Trying to be thorough, I found the name of a control that shouldn't be on the ui object but is (lblRBG1). I did: grep -iR 'lblRBG1' * It returned 0 files which was a surprising to me. With all this digging, I'm feeling much more comfortable with how the projects run. I plan on creating a new window with the the layout I want. I'll just switch to using the new window and delete all references to ui_mainwindow. Once I stop looking, I'll probably find the cause next week some time ;) And it's likely operator error :D Thanks again for the suggestions.
  • TCP connection for file transfer

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    VRoninV
    @JonB said in TCP connection for file transfer: Maybe it does It does, but for a more generic case you can use: const qint64 originalPos = out.device()->pos(); out << qint64(0); const qint64 sizeOfHeader = out.device()->pos() - originalPos; out << image; out.device()->seek(0); out << static_cast<qint64>(block.size() - sizeOfHeader );
  • Background image

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    G
    Thanks I'll give it a go
  • Qt fails to copy file on ubuntu.

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    Q
    @JonB OK. Thank you very much!
  • Compile qt-5.4.1 with vs2017 got error.

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    J.HilkJ
    @mic19 I would suggest you to consider using Qt version 5.6.3 That's an LTS version (Long term support) that means 3 year bug fix support (till March 2019) it comes with msvc2013 and 2015 precompiled libs.
  • UWP and openGL version problem

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    No one has replied
  • QT5.11.2 QML treeview select function do not alternates the row color?

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    J.HilkJ
    @jimfar said in QT5.11.2 QML treeview select function do not alternates the row color?: maybe it is a QT bug unlikely, my guess is, the "alternate row color" is not bound to selceted property but rather to focus. You give focus to the tree item by clicking on it.
  • QTimer will not connect

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    jsulmJ
    @BKBK Take a look at the documentation: http://doc.qt.io/qt-5/qobject.html#connect
  • Implement low pass filter.

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    JKSHJ
    @Siddhartha said in Implement low pass filter.: Unfortunately, I'm new to both. No problem. OK, here's a 5-step approach I recommend for you to reach your goal: Learn how to build and run an existing program Learn how to modify an existing program Read about the basics of different types of low-pass filters Convert a low-pass filter equation into C++ code Integrate the C++ low-pass filter code into the serial port plotter (just like step #2) Let's start with step #1. I see that you already have Qt Creator; are you able to build and run the serial port plotter software on your PC?
  • QGraphicsScene Scene List show in TableView

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    SGaistS
    Hi, What exactly do you want to show ?