Installation and Deployment

Yes, Qt is kind of braindead :-) before QApplication a(argc, argv); not many things work; it tries to load the libqcocoa.dylib when you specify that Fusion setting line, and because you did it before the QApplication constructor, Qt hasn't found and read in qt.conf file (written by macdeployqt, it tells Qt where to find libqcocoa.dylib). That's why moving the Fusion setting after makes Qt much happier. P.S. Actually you can get around this error in another way than by moving the Fusion setting line: by copying the PlugIns folder (created by macdeployqt in example.app) and place it together with the .exe/ELF file (MacOs/example). Because then Qt can load the Cocoa plugin without having read any qt.conf file.

@d.terhaar Thanks! This fixed me on this post: https://forum.qt.io/topic/61001/broken-qt-5-5-macdeployqt/3 I moved my Fusion style line AFTER the QApplication a(argc, argv); line, unlike previous documentation I had read for this, and the problem went away. I was now able to deploy without Cocoa issues. I had been racking my brains for 3 hours on this. I'm so glad you did the difficult digging to find the fix.

Thank you. It worked!!!

@Prezes are you referring to QDir? This post is about scripts in Qt Installers. Are you trying to access Program Files x64 in Qt or Qt Installer? Note: "Program Files x64" in 64 bit Windows is actually named just "Program Files" and it does not exist at all in 32-bit. So if you are trying to do this in Qt Installer Framework then my solution in this post also applies to you :)

Since you're using Ubuntu either use the apt-get command or the package manager

Hi @JKSH, @Leonardo, Many thanks for your tips and apologies for delay. I got distracted by another task, but will get back to this one again. Just to report what happened so far. All my attempts on one machine failed. Switching to another computer I managed to to statically build Qt and Qt Creator once (using your receipts), but failed to reproduce that again. I'm putting all this down to my inexperience on Windows platform. However, I have learnt a lot and I'll get back to this problem again. BTW, working with VS is not as scary as it originally looked :-). Once I managed to install it, that is. The installation of VS was a pain as due to my inexperience and some bugs. E.g. installing VS via RDC produces a transparent window - I waiting for hours for something to happen, then tried another version of VS, ... Best, J.

You need to provide all needed Qt DLLs with your program, else it will not work. See here: http://doc.qt.io/qt-5/windows-deployment.html#the-windows-deployment-tool

Hi and welcome to devnet, A VM is not a problem, you can install and do Qt 5 development on e.g. VirtualBox, VMWare or Parallels without any problem. However, it's not sure that Cloud9 provides an X server which is needed to use the xcb plugin. You should check with the Cloud9 people about that.

Yeah I've seen that, usually occurs because you have global/static variables with QDatabase contents or similar. If you have, move them to your MainWindow class. Qt and global variables do not mix well :-)

@selster said: I can now build and run some example project !!! Great! However, if I try to run the example "fancybrowser", I get build errors like: Warnings while parsing QML type information of C:/Qt/5.5/mingw492_32/qml/QtPositioning: C:\Qt\5.5\mingw492_32\qml\QtPositioning\plugins.qmltypes:1:24: Reading only version 1.1 parts. C:\Qt\5.5\mingw492_32\qml\QtPositioning\plugins.qmltypes:10:5: Expected only Component and ModuleApi object definitions. I recommend you start with simpler examples. The browser is quite complex; I don't fully understand it myself so I can't help you with those warning messages. See http://doc.qt.io/qt-5/gettingstartedqt.html

qt.conf is a run time configuration file used by the Qt framework libraries, one of the configuration items is the location of the Qt plugins. You do not access the qt.conf file, you provide it to tell Qt where to find its plugins. As SGaist says above macdeplyqt is a tool that works with qmake to make a package suitable for deployment on OS X.

So if i run VS2015 with qt-everywhere-opensource-src-5.5.0-rc i should be happy? No, definitely don't do that. "-src-5.5.0-rc" means source code of release candidate of Qt 5.5.0. First of all we're at 5.5.1 version now so there's no point in using a release candidate version of 5.5.0. Second - it's a source package. It means you need to build it for your compiler first.

@Chris-Kawa Thank you very much.

@Alicemirror Though too late reply yet worth posting. If qrc is not used then Absolute path of qml file like "/home/manoj/QT/qmlFileDemo/main.qml" can solve the problem.

Finally I used a similar library in server side. pHash library wasn't compatible with Qt5

Hi, without those qml/javascript stuffs that could slows down the app, have you proof of that? Best practice is to write your code; test profile and then optimize slow parts. In .pro file i have: QT += quick quick-private core-private gui-private declarative-private qml-private and in .cpp file - #include <private/qquickrectangle_p.h> you're using private classes that are not exposed in the public libraries

Good to hear. Just want to add, most of the big wheel programs that are built on Qt, usually are linked/built statically, which means no dlls will conflict for a scenario like yours. I'm guessing, but if you're adding a plugin to perhaps VLC?, then all of their Qt stuff (including their own qwindows.dll and qt.conf etc.) are linked together into one humongous 12 MB file (C:\Program Files (x86)\VideoLAN\VLC\plugins\gui\libqt4_plugin.dll) so the double dll syndrome never occurs :-)