@Milav said in segmentation fault: the difference between host pc and Embedded target board is only QT source. Host pc => qmake (qt version 5.4.0 ) Embedded target => qmake (qt version 4.8.7) You should have stated these settings from the very beginning... :-) Anyway, could it be possible that you build Qt 4.8.7 for PC (host) and build your example again with that Qt version and run in PC to see what happens.

Finally I changed reading mode to read directly from the data file. It's most faster and just I was care to encode data when reading to keep special charcatars. Thanks all for your ideas

@Sivamani-V said in How to connect to mysql server in ubuntu 16.04?.: QMYSQL Driver not loaded. Available drivers: QMYSQL QSQLITE QMYSQL3 This gets asked so many times, here & elsewhere. Googling for your message will bring up many hits. Under Linux/Ubuntu it's usually libmysqlclient or libqt5sql5-mysql or similar which is missing/has dependencies missing/wrong version.

Hi You are mixing old syntax with lambda which it cannot do. With lambdas you cannot use the SIGNAL() macro. Has to be the new syntax. I used QObject::connect(&but_submit, &QPushButton::clicked, [&]() {... which compiled fine and did show the entered string. But you seems to be using Qt-4.8.5 at and new syntax first came in Qt5 so i guess that is why you get errors. So basically, with that old Qt , you cannot do it in main. You need a QOBJECT based object to send signals to. In that old Qt, its not possible to connect to functions. Only to member slots in a class. You must use that so old Qt ?

@define-qt You can be more specific using the name of object as identifier in style sheet sintaxe QLineEdit#ObjectName { border:0; }

JS handler can be added via evaluateJavaScript, and Qt bridge used to provide actual handling via exported QObject I've considered adding API for C++ event hadlers, but that would require some development effort

yes, calling setfilter will call select using the filter argument as WHERE clause so resetting the whole model

Hi Paul, I appreciate the kind reply and thank you. Those were good suggestions. I should of been truncating from the beginning instead of recreating the file, this is a better approach. Implementing this did solve the problem with the monitor path directly to my file. Implementing you other suggestion however did not work (Linking watcher to the directory), which I don’t fully understand since I thought it would look for any changes within the directory including the file change. Best

achieve make it work like this: property string archivo: null function ubicacion(x) { archivo = x; return archivo.substr(8); }

Lo resolvi ya con este ejemplo http://doc.qt.io/qt-4.8/qdeclarativedynamicobjects.html Lo malo es que tengo que programar varias cosas que con el codigo anterior hacia perfectamente. pero ahora puedo crear las ventanas dinamicamente y cada una es independiente. no estan mas en una lista o cuadricula.

Hi Main windows is a bit special since it has "central widget". which there to allow to define areas around it for Dock windows. That is why we insert widget first. For all types of other widget we would insert directly. QWidget* centralWidget = new QWidget(); QVBoxLayout *layout = new QVBoxLayout; centralWidget->setLayout(layout); layout->addWidget(st); setCentralWidget(centralWidget); seems fine. For centralWidget , u can then use the Stacked. My mainWindow code actually looks like: MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { setLayout(layout); // that sets directly on mainwin. not sure it does what we think. You can just single step and see the values to find out why u crash. Sorry, i cant spot it. Running it helps. I think u need a setCentral also. That is the reason no 2 to why i like UI file so much. no crashing as u can only insert legally when visually :) And no code to try to spot bugs in. I think u need new widget widget as central new layout layout to widget inset stacked to that layout and then the page stuff

@Chillax You're Welcome :)

@SGaist said: QNetworkAccessManager. ok, i know by Qjson (but is for a 3rd and i preffer use the official) i forget the existence of QNetworkAccessManager.

@Bart_Vandewoestyne said: we're storing our Qt build in our version management system This is a strange thing to do, since Qt guarantees binary compatibility between minor versions, but well, you're free to choose. Unfortunately, I don't see how you could decrease the size further, beside deleting the docs, as the libraries are in the /lib directory and they're the next biggest size. Maybe store only the libs that you're using, i.e. these that you're going to deploy. No point in keeping QtXml if you're not using it, right?

The most important thing: QT += widgets in your pro file. Otherwise the port itself is pretty painless, see here

@SGaist OK. Thanks for the answer. I'll give a try.

@Chris-Kawa, Thank you very much for guiding me , it is very useful to me

Hi and welcome to devnet, What version of Qt 4.8 are you currently using ?