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This is where all the desktop OS and general Qt questions belong.
83.6k Topics 457.8k Posts
  • Draw big things with Painter outside main window.

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    B
    @mrjj Yeah, when I had problem with this I placed painter->scale(0.5, 0.5); in loop, I dont know why. Now I placed it before loop and it's working, but the problem is when the pattern is small. When I tried to "back" to original scale in QML (from 0.5 in C++ to 2.0 in QML) the image is blurry. I will try to do pattern size detection and then - if pattern is big scale is down, if pattern is small then do nothing / scale it up.
  • Cannot open file - QProcess

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    jsulmJ
    @Chaki said in Cannot open file - QProcess: process->start("python3 /home/someFolder/test.py"); This should be process->start("python3", QStringList() << "/home/someFolder/test.py");
  • qbytearray error during debugging the program

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    JonBJ
    @Wasee As @sierdzio says. It's for you to sort out, and in any case if you get an assert and are running under a debugger you should get a trace back to whatever line of your own code caused the problem. Your code does little about checking array indexes/bytes received etc. so it's not surprising. I would hazard a guess that your problem might be in your WifiSniffer::onReadyRead(). Apart from checking bounds there, what you have not allowed for is that when bytes arrive and Qt emits readyRead signal which invokes your slot, there is no guarantee at all that you will have received all the bytes you are expecting to constitute a full "message" or "frame" in your protocol. Qt only guarantees that somewhere between just 1 byte and the full number has been received. It is up to you to call code to buffer whatever you have received so far and append what you receive now, until you have whatever you need to proceed.
  • In the process of applying qt developed on Windows to Linux

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    JonBJ
    foreach (... in ...) is a C# construct, and for (... in ..) is a JavaScript one. Neither is right for Python. Not for C++, where Qt has a foreach() macro with different syntax. The for each (... in ...) is an MSVC-only C++ construct, per https://docs.microsoft.com/en-us/cpp/dotnet/for-each-in?view=msvc-160, and it warns: This non-standard keyword is available in both C++/CLI and native C++ projects. However, its use isn't recommended. Consider using a standard Range-based for Statement (C++) instead. :D
  • Is it possible to configure cross-compilation using Creator?

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    jsulmJ
    @IknowQT said in Is it possible to configure cross-compilation using Creator?: What can I do next? I already wrote what you need to do. I also asked you a question which you did not answer...
  • This topic is deleted!

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  • What should I return in eventFilter?

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    @eyllanesc Ok, I understand :)
  • This topic is deleted!

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  • GUI change with signal and slot

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    jsulmJ
    @duckrae First remove all that thread stuff
  • How create a delay 1 nano second or 1 usecond with QTimer in Qt? is it possible?

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    stackprogramerS
    @JoeCFD said in How to create a delay 1 nanosecond or 1 second with QTimer in Qt? is it possible?: Are you sure? In that link: there is the scheduler, which probably allows no sleeps that are shorter than an timeslice (somewhat around 4 ms - 10 ms, depending on your windows and machine). sleeping less than that is not possible When I used the before method for a nanosecond I measure 100000nano seconds.....the difference was so much.... std::chrono::nanoseconds(nanosecond).count(); but with the up method, I can delay 1000 nanoseconds or 1micro second about accurately ..... My os is ubuntu,qt,gcc...not windows... This delay function executed on a QThread.... thanks good time
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    @jsulm It is indeed a lib naming problem. After changing to libtest.dylib, it should be like this: LIBS += -L$$PWD/libs/macos/ -ltest.
  • How to detect "user interface idiom" of a screen?

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    @sierdzio I've learned that the pinephone's screen 0 is called DSI-1. I assume it's named after Display Serial Interface.
  • Qt-based programs fail to start in 5120x1440

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    SGaistS
    The issue was auto solved because there has been no feedback to the request for tests. If you can do what was suggested there and add some more information to it then the bug can be reopen.
  • Network problems

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    SPlattenS
    @Kent-Dorfman It is solved.
  • QNetworkInterface getting a name that means something?

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    Kent-DorfmanK
    mark as solved?
  • Inserting image and date into sqlite3 database

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    Kent-DorfmanK
    YMMV inserting images into a database. BLOB field support is often a special case, if supported by the DB at all.
  • How to have GUI based program wait until user enters acceptable input

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    @JonB @JoeCFD Okay I just switched to using QMessageBox then, I had not thought about running this on different operating systems. Thank you for the tip. @Christian-Ehrlicher thank you for the textChanged input. I am going to try to implement that
  • How add a Crypto++ Library version 8.6 in Qt 6

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    artwawA
    @Alby Download binary and headers. In your .pro file add INCLUDEPATH, DEPENPATH and LIBS manually or as described in the manual. After that you can #include headers in your sources. If you do #include but QtCreator complains that file can't be found - you did the above wrong.
  • Top-Level Window vs Window in QGuiApplication?

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    JonBJ
    @CJha Yes, exactly that.
  • Get all items from within groupbox of pyqt

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    JonBJ
    @poordev123 Just so you know: it's QObject::findChildren() so you can actually call it on any QObject, and that includes any and all QWidgets. QGroupBox is a QWidget itself, and there are other such "container" widgets for which this works.