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This is where all the desktop OS and general Qt questions belong.
83.6k Topics 457.7k Posts
  • Does QStackedWidget processes all pages simultaneously?

    Unsolved qstackedwidget pages gui
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    SGaistS
    Hi and welcome to devnet, QStackedWidget does not care nor handle what do the widgets inside it. What will not happen is UI updates but all the rest will. What you can do is disable these processing when the widgets are not visible if it makes sense.
  • What SIGNAL to monitor for incorrect QProocess ?

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    JonBJ
    @AnneRanch You have asked this so many times, and been answered. You cannot execute hcitool -i hci0 scan --flush | tee /tmp/temp as the command in process ->start(command). The answer is always the same: process ->start("/bin/sh", QStringList() << "-c" << command); YES, I can go back to passing data to "bash"... BUT bash script does not accept some standard options likes "|" and "tee". Completely incorrect. It is only either /bin/sh or /bin/bash which does accept and interpret |. tee has nothing to do with the shell, and works fine from either. If I do pass QSTring to QPProcess - what is the corrent systex for passinf "system" function ? There is no system-anything to pass to QProcess. system() is an alternative to using QProcess. You are better using QProcess in Qt programs and not system(). There is nothing system() does that QProcess() cannot do, but there are things you can do with QProcess which cannot be done with system(). You could save yourself time but not trying to use system(), I have shown you the equivalent process ->start() to use instead. Which one of QProcess standard SIGNALs should I monitor for possible error? void errorOccurred(QProcess::ProcessError error) errorOccurred() is the signal for errors launching QProcess. You will doubtless be interested in other things which happen that are not process errors, even if you might think they should be. They may be reported by reading stderr (readyReadStandardError()) and possibly stdout too. For the simplest case just use const char *command = "hcitool -i hci0 scan --flush | tee /tmp/temp"; process ->start("/bin/sh", QStringList() << "-c" << command); process->waitForFinished(); qDebug() << process->readAllStandardError(); qDebug() << process->readAllStandardOutput(); You should also connect on the errorOccurred signal, just in case.
  • Generic way to restore / set widgets to initial state ?

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    Pl45m4P
    @SPlatten said in Generic way to restore / set widgets to initial state ?: thought I'm going to implement a signal, something like dataUpdate where the controls will connect to this signal and they're own slot will update the control. Just do it :) You know best, how your widgets should look in your initial state or how to "reset" them. Can't be that hard to think about everything you want to undo / reset and then write a function which does so. Some function or slot which can be connected to your signal and which will clear, uncheck, flush, whatever... everything. Btw: This behavior is not very uncommon. A dialog with some input fields and a button to "clear" / reset all input, while keeping the rest. On QLineEdits you can simply call clear() (you probably know that)... for every other widget and maybe even custom ones, we can't help you, how your initial state might look like and how to get there :)
  • This topic is deleted!

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  • Setting background colour of qtableview

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    JonBJ
    @andi456 That's fine, QStyledItemDelegate seems best. What triggers the paint method of QStyledItemDelegate? Just whenever it needs painting/re-painting! QStyledItemDelegate receives a QModelIndex(). That contains the row. You can find the "column x" with the desired color via siblingAtColumn() in the row.
  • How mathematical operations done correctly in qtCreator?

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    Christian EhrlicherC
    @Wasee said in How mathematical operations done correctly in qtCreator?: I am adding/subtracting two string values You can not add/substract string, only numbers... see QString::toInt() and similar QString functions.
  • No sound in exe file on different PC

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    jsulmJ
    @harish__rajora Found this: https://forum.qt.io/topic/41943/platform-plugin-windows/8 Check the last post there.
  • At the paint event after applying the style sheet to the button

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    Pl45m4P
    @IknowQT Why you need stylesheet when you use the paintEvent anyway? How does your paintEvent look like? Do you call the base implementation of QPushButton::paintEvent afterwards? It could overwrite your custom style
  • This topic is deleted!

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  • How to include so files (libraries).

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    J
    @jsulm said in How to include so files (libraries).: @jenya7 said in How to include so files (libraries).: I don't understand why do I need so files Well, you want to use a library (.so), right? How else should it work? Or is your library header-only? " just can't figure what is a library in the folder" - it is a *.so file in the build folder of your library project. Thank you. Now it makes sense to me. :)
  • StackWidget objects in qt designer not resizing

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    S
    @LT-K101 said in StackWidget objects in qt designer not resizing: But when I used all the layouts in Qt designer it reposition the objects in a different manner which is not the way i arranged the objects. I have to disagree here. When you don't use a layout, the position of widgets is in relation to the top left of the widget they are contained in: The spacing between the widgets stays the same in your full screen view, and also their relative position in relation to the top and the left. I am not entirely sure what you are trying to achieve or why a layout would break the thing you are trying to achieve. With the way things are layout in Qt Designer right now, I would just apply a grid layout to the parent widget (I believe this is a little complicated with a stacked widget; you might have to select the correct widget in the Object Inspector on the right to apply the layout). If you want some space between some of the widgets, add horizontal or vertical spacers (they can be found almost at the top of the list on the left). I tend to use horizontal spacers with a fixed width of 20 pixels from time to time.
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    jsulmJ
    @dounreay said in Qkeychain - error: undefined reference to &#x60;__imp__ZN9QKeychain16WritePasswordJobC1ERK7QStringP7QObject': No, the libraries and the includes are in different sub directories This is not what I asked. And there is also no need to move the lib. What I asked was: was this library built using same compiler or a different one? You can't mix binaries built with different compilers (like MSVC and MinGW) in same application.
  • btchat example not working between windows 10

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  • How to start a QEventLoop and triggers a function every 5 seconds.

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    Christian EhrlicherC
    The detailed description should help here. Create timer, connect timeout to the your custom slot, do your work and checks in there.
  • Test successful but the application crashes

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    Christian EhrlicherC
    As always - start your app with a debugger and see where it crashes, fix it. From what I see erdBridget is not initialized so delete will crash
  • Scroll gestures do not work.

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    SGaistS
    Hi, Aren't you missing something like: QScroller::grabGesture(&tree, QScroller::TouchGesture); ?
  • Qt 6.2 QImage JPG over 33,547,526 pixels no longer loads

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    R
    @Christian-Ehrlicher @hskoglund @SGaist Thanks very much gentlemen!
  • QSpinBox doesn't send signal valueChanged() anymore

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    kshegunovK
    @Christian-Ehrlicher said in QSpinBox doesn't send signal valueChanged() anymore: No need - a simple look in the documentation reveals it. But who needs a documentation ... I assume it's the overload resolution, I wanted it confirmed.
  • How to pass parameters via contextmenu addActions() ?

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    Christian EhrlicherC
    @nicholas_yue said in How to pass parameters via contextmenu addActions() ?: [this, v1=p1, v2=p2]{ Why do you want to rename them? A simple [this, p1, p2] is enough.
  • Error with customsortfiltermodel example

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    @Christian-Ehrlicher it works! Thank you guys!