General and Desktop

• 

  UNSOLVED ProgressBar appearance change after deploying application
  • Amazonasmann

  6
  0
  Votes
  6
  Posts
  67
  Views

  

  @amazonasmann said in ProgressBar appearance change after deploying application:

  I found my solution

  Great. If your issue is really solved, please don't forget to mark your post as such! Thanks

• 

  UNSOLVED QSplitter child widget sizes affect eachother
  layout splitter • • karolus2c

  3
  0
  Votes
  3
  Posts
  59
  Views

  

  PyQt5 5.13.0, installed using pip.

• 

  Library doesn't open
  • manuja

  33
  0
  Votes
  33
  Posts
  3023
  Views

  

  @jsulm thank you for your answer. Do I understand this right, that these basic settings should work?

• 

  UNSOLVED Associating one menu with two QToolButton
  • Ayush Gupta

  5
  0
  Votes
  5
  Posts
  43
  Views

  

  @umod-47 you can, but you shouldn't, let me quote the documentation

• 

  UNSOLVED How to combine stylesheets and custom widget painting?
  • Vadi2

  2
  0
  Votes
  2
  Posts
  30
  Views

  

  It will not work - either use CSS or a custom Style. Afaics the stylesheet stuff is internal so you can't access it.

• 

  UNSOLVED QtRO and GUI
  • addebito

  2
  0
  Votes
  2
  Posts
  48
  Views

  

  Hello everyone,

  I made a lot of test but I can't understand where is the problem.
  There is someone that can post an example of a client (QRemoteObjectNode) in a C++ widget application or run my example please?

  Any help will be much appreciated.
  Thank you.

• 

  UNSOLVED [MYSQL-Qt] Create plugin MYSQL for Qt on MAC
  • Quang Phu

  3
  0
  Votes
  3
  Posts
  86
  Views

  

  Hi @James-Hankins,
  I haven't tried on Windows yet. but I think you can take a look with this post
  https://forum.qt.io/topic/96506/qtdriver-not-load
  May it help.

• 

  UNSOLVED What is current (2019) recommended process (complete) for building a MySQL Driver for use with Qt on Windows?
  • James Hankins

  2
  0
  Votes
  2
  Posts
  37
  Views

  

  Hi,

  What exact error are you getting ?

• 

  UNSOLVED Numbers not getting rendered
  • soumya

  4
  0
  Votes
  4
  Posts
  79
  Views

  

  Can you provide a minimal compilable example including the font ?

• 

  SOLVED directoryOf function QT4 -> QT5
  • sandro4912

  8
  0
  Votes
  8
  Posts
  89
  Views

  

  Yeah i already marked it. I Gues ś questions like this happen after coding to many hours...

• 

  UNSOLVED Slow debugger
  • LorenzoCorti

  2
  0
  Votes
  2
  Posts
  38
  Views

  

  Hi @lorenzocorti,

  Bumping my head on the wall: what am I doing it wrong?

  Stop bumping! Probably you don't do anything wrong?

  With Qt 5.95 and 5.12.5 compile takes twice the time it takes with Qt 4

  I remember, someone complained about this years ago. IIRC, the problem is that the Qt headers nowadays include lots more of stuff, including STL.

  To overcome this, you can use precompiled headers and/or class forward declarations. I assume you already compile with make -jX where X is the number of cores?

  but debugging is unacceptably slow (the spinner lasts for about 20 seconds on screen before showing actual breakpoint data).

  Which debugger version is that? We have a similar report: QTCREATORBUG-22896 but so far it's hard to reproduce. You might want to comment on the report, and maybe you have a minimal reproducer.

• 

  UNSOLVED Linuxfb Keymap FR
  • Sylvain33700

  1
  0
  Votes
  1
  Posts
  13
  Views

  No one has replied

• 

  SOLVED Getting user confirmation before opening external links in a QTextBrowser
  • Robert Hairgrove

  5
  0
  Votes
  5
  Posts
  52
  Views

  

  SOLVED: I had another slot connected to the sourceChanged signal, and it was causing side-effects.
  Thank you, @JonB for pointing me down the right path for fixing this!

• 

  UNSOLVED How to run lupdate with a QMAKE CONFIG?
  • devjb

  1
  0
  Votes
  1
  Posts
  22
  Views

  No one has replied

• 

  UNSOLVED Moving QGraphicsView when moving the mouse
  • Infestor

  1
  0
  Votes
  1
  Posts
  20
  Views

  No one has replied

• 

  UNSOLVED Efficient way of visualizing camera images without copying data to a Qt datastructure
  • Roman1

  7
  0
  Votes
  7
  Posts
  84
  Views

  

  Hi,
  never did someting like displaying 8 pictures parallel. Most of my work uses only a single output.
  For a fast output in my ad-scanner i use SDL, its a bit tricky to use but very fast. With SDL you can also display your Images without creating QImages.
  I think its worth a try.

• 

  UNSOLVED Manage Qthread -resource creation and deletion
  • meganathan

  8
  0
  Votes
  8
  Posts
  99
  Views

  

  Ok thanks,..i will try it out

• 

  UNSOLVED Newest QTCreator (4.10.0) does not execute all build steps anymore when building through context menu
  • devjb

  9
  0
  Votes
  9
  Posts
  103
  Views

  

  Hi @devjb,

  thanks for the report and the example project.

  I have two comments for that:

  Please don't share the .pro.user file. It is only thought to be used on your single machine. Please don't use CONFIG+=ordered, please refer to https://blog.rburchell.com/2013/10/every-time-you-configordered-kitten-dies.html for more information

  Regards

• 

  SOLVED If the file name is too long, how to make the file selection drop-down box of the QT editor display the file name completely?
  • canid

  6
  0
  Votes
  6
  Posts
  99
  Views

  

  @canid said in If the file name is too long, how to make the file selection drop-down box of the QT editor display the file name completely?:

  I recommend that the editor be improved here.

  Then you should provide a change request at Qt bug tracker. Asking here for features will most probably not help.
  https://bugreports.qt.io/secure/Dashboard.jspa

• 

  SOLVED Linker issue with CUDA API libraries
  • Cobra91151

  6
  0
  Votes
  6
  Posts
  1132
  Views

  

  @vaibs1224

  Can you provide some more information?

  Which compiler? 32 or 64 bit? Can you show your .pro file and the actual linker command from the Compile Output?
• 

  This topic is deleted!
  • TapTap21

  1
  0
  Votes
  1
  Posts
  11
  Views

  No one has replied

• 

  UNSOLVED QMediaPlayer does not play many formats
  • Mikeeeeee

  17
  0
  Votes
  17
  Posts
  183
  Views

  

  @davecotter said in QMediaPlayer does not play many formats:

  i'm biased against forcing the end user to download and install an app dependency

  Then provide them with your app.
  The problems with codecs are: licenses.
  That's why Linux distributions often do not provide all available codecs by default and the user of the distribution has to install them explecetly (like on Ubuntu with bad/ugly versions of GStreamer plug-ins from universe repository). Same for Qt I guess: Qt projects does not want to get in troubles because of providing codecs for not really free media formats (not free, full of patents, ...).

• 

  UNSOLVED Help tracking down a Qt Widgets sizing problem
  • Vadi2

  3
  0
  Votes
  3
  Posts
  59
  Views

  

  Both links work, and I had to use them because the forum has limitations on gif size - sorry!

• 

  SOLVED problem with emit a signal!
  • Saeed_Nowroozi

  3
  0
  Votes
  3
  Posts
  73
  Views

  

  The idea is simple. Imagine you would like to know if something happens and based on it, you need to take an action. This scenario occurs in Qt via signal-slot approach. Knowing if something happens is usually carried out with emitting a signal. Taking an action is usually done via slot.

  Now imagine you have Student Class and you need to know if the name of the student has been changed. The following simple minimal working example illustrate this scenario:

  student.h

  #ifndef STUDENT_H #define STUDENT_H #include <QString> #include <QObject> class Student : public QObject { Q_OBJECT // <- very important for signals and slots macros public: Student(); Student(const QString &name, QObject *parent=nullptr); QString get_name() const { return m_name; } void setName(const QString &name); signals: void nameChanged( const QString &name ); private slots: void nameChangedAction(const QString &name); private: QString m_name; }; #endif // STUDENT_H

  student.cpp

  #include "student.h" #include <QDebug> Student::Student() { } Student::Student(const QString &name, QObject *parent) : QObject(parent), m_name(name) { QObject::connect(this, SIGNAL(nameChanged(const QString&)), this, SLOT(nameChangedAction(const QString&)) ); } void Student::setName( const QString &name ) { m_name = name; emit nameChanged( name ); } void Student::nameChangedAction(const QString &name) { qDebug() << "Student's name has been changed to " << name; }

  main.cpp

  #include <QCoreApplication> #include "student.h" int main(int argc, char *argv[]) { QCoreApplication a(argc, argv); Student student("Smith"); student.setName("Bill"); return a.exec(); }

  Remember: you don't create a body function for a signal. You just declare it. You will get an error if you do so. Play with this example to understand the signal-slot approach.

• 

  UNSOLVED Displaying data in hex format
  • admkrk

  6
  0
  Votes
  6
  Posts
  85
  Views

  

  @christian-ehrlicher said in Displaying data in hex format:

  You did not took a look at the documentation I pointed you to - toHex() returns a new QByteArray, it does not modify the current object: "Returns a hex encoded copy of the byte array. "

  I did look, but missed the part about a copy.

  @mpergand said in Displaying data in hex format:

  It seems that what you want to do is some sort of HEX DUMP :

  Yes, that is pretty much what I am looking do.

  Thank you both, if I can ever get a good nights sleep I should be able to figure something out.

• 

  UNSOLVED Access violation by button click due to long running process
  • meursault

  5
  0
  Votes
  5
  Posts
  75
  Views

  

  @meursault said in Access violation by button click due to long running process:

  I did get a call stack on the crash that did show me that it was indeed an access violation caused by QT handling a clicked signal.

  Are you allowed to post the full stack trace? Change the names of your application's functions to preserve confidentiality, but don't change the structure.

  Also, compare the Release mode stack trace with the Debug mode stack trace -- do you notice anything unusual?

  Am I just not seeing the full picture somehow and this access violation caused by a QT clicked event is actually caused by something else?

  I'm sure that the debugger isn't lying when it says that the access violation occurs at the instant when QMetaObject::activate is called. But we don't know whether it's QMetaObject's fault or not.

  Think about the button and the signal. Is it always the same button that causes the crash, or do different buttons cause it? Look at the signal parameters -- are they deletable? Are they custom types? Look at the slot(s) connected to those buttons -- does the receiver object get deleted at any point?

  Also, which thread processes the file -- your GUI thread, or a secondary thread?

  Does the problem still exist if you build your code against Qt 4.8.7 (the last version in the Qt 4 series)

  I wouldn't be surprised but normally when I run in release with a debugger attached it shows me somewhat useful information when it crashes. I'm sure this is not as reliable for debug information but I would just like to know next time I encounter a weird crash that says it's being caused by QT.

  That's the nature of bugs: We know how the system is supposed to behave, but since it is misbehaving we can't make any assumptions on what's going on. So, the most systematic way forward is to gather as much detailed evidence as feasible. It could be a bug in your code; it could be a bug in Qt's code.

  You might even encounter a Heisenbug where the program's behaviour changes when you run it in Debug mode. This could either frustrate you to no end, or it could provide a different set of clues to help you track down the bug.

• 

  UNSOLVED my app blinking on ubuntu
  • mmjvox

  2
  0
  Votes
  2
  Posts
  41
  Views

  

  Hi,

  Did you test your application using your distribution provided Qt ?

• 

  SOLVED How to run VBA function using QAxObject?
  • Pauly

  10
  0
  Votes
  10
  Posts
  120
  Views

  

  @pauly said in How to run VBA function using QAxObject?:

  BTW I use "run" instead of "evaluate" with gives a little bit more flexibility...

  Nice! I remember testing "Run" but I couldn't get it to work, only "Evaluate", must be getting old :-)

• 

  SOLVED Spacing and alignment of buttons in a QToolbar
  • Robert Hairgrove

  3
  0
  Votes
  3
  Posts
  40
  Views

  

  @mrjj Fantastic! You have saved me so much time ... thank you very much!

• 

  SOLVED QNetworkReply which is returning socket timeout error in compatibility mode on windows 7
  • DLHTS

  11
  0
  Votes
  11
  Posts
  142
  Views

  

  @aha_1980 Done.

• 

  SOLVED Having trouble with QFrame and palette...
  • Robert Hairgrove

  10
  0
  Votes
  10
  Posts
  61
  Views

  

  OK, I finally got it to work with style sheets. :) Here is my event filter now:

  bool SbblHelpWindow::eventFilter(QObject *watched, QEvent *event) { QString col_in = "green;"; QString col_out = "rgb(238, 238, 236);"; // light gray, this is what Designer gives me QString col_to_set = "background-color:"; bool ok = false; if (event->type() == QEvent::FocusIn) { col_to_set.append(col_in); ok = true; } else if (event->type() == QEvent::FocusOut) { col_to_set.append(col_out); ok = true; } if (ok) { if (watched == ui->treeContents) { ui->frameContents->setStyleSheet(col_to_set); } else if (watched == ui->lsvBookmarks) { ui->frameBookmarks->setStyleSheet(col_to_set); } else if (watched == ui->txtPageView) { ui->framePageView->setStyleSheet(col_to_set); } } return false; }

  Thank you very much for the tip, @mrjj !

• 

  SOLVED QNetwokrAccessManager: QNetworkReply::SslHandshakeFailedError
  • Infinity

  6
  0
  Votes
  6
  Posts
  76
  Views

  

  Thanks for your help. It is working now.

• 

  UNSOLVED Call Python Script with Qt C++
  • gblessed

  2
  0
  Votes
  2
  Posts
  36
  Views

  

  Hi
  You can either call the python script via QProcess or
  try full integration.
  https://github.com/pybind/pybind11
  Also consider the new PySide2 bindings.

• 

  SOLVED Unable to create file. File name too long
  • Poldi

  4
  0
  Votes
  4
  Posts
  77
  Views

  

  @Poldi: Then please mark the topic as solved

• 

  UNSOLVED QTextStream(stdout) use of undeclared identifier stdout
  • Bill52

  13
  0
  Votes
  13
  Posts
  413
  Views

  

  @bill52 Just to close this topic in case anybody reads it.
  The issue has never been solved. Reinstalling Qt didn't help.

  Later KDE was installed then Qt 5.13.1 via the offline installer.
  After some teething issues it now works. (since yesterday)

  As a final thought: the offline/online installers failed when i run them from the GUI (dolphin).
  The offline installer succeeded when run it from the terminal.

• 

  UNSOLVED On macOS Retina display, 3D scene occupies only a quarter of what it should
  • m3g1dd

  3
  0
  Votes
  3
  Posts
  65
  Views

  

  @sgaist I'm studying it now. Thanks =)

• 

  SOLVED Qt Creator 4.10: What does it mean "WebAssembly"?
  • bogong

  13
  0
  Votes
  13
  Posts
  257
  Views

  

  @lorn-potter Any chances to release a prebuild version of Qt for wasm optimize for space(compiled by Oz) but not speed?

• 

  SOLVED Qt for webassembly do not support ssl?
  • tham

  8
  0
  Votes
  8
  Posts
  135
  Views

  

  Use emscripten to call the js api and library work.

  All you need to do are

  include js script in the app_name.html, before the <script type='text/javascript'>

  Use EM_JS to create a c function which called the js libs, I wrap them in the nameless namespace, not sure this is needed or not.

  I do not add the global variable into Module or window object, maybe this matter, or maybe not.

  Qt for webassembly is an amazing technology, thanks for the efforts.
  Today we still suffer from huge binary size and immature core functions, hope these issue could become better in the future

• 

  SOLVED QSqlDatabase and local Sqlite 3. Abnormal application stop.
  • bogong

  11
  0
  Votes
  11
  Posts
  124
  Views

  

  @christian-ehrlicher In some cases it's only one way ... first of any - license ... That why I am asking and doing such complexity.

• 

  UNSOLVED same actions to execute different slots
  • user4592357

  11
  0
  Votes
  11
  Posts
  70
  Views

  

  @christian-ehrlicher
  i'm thinking of another solution, have a method in actionHandler to take the rows to be updated. the table will set the selected rows numbers, and the tree will set *. that way processing will be done the actions handler now.