Qt way to get libraries path - qt

I have several QPlugins (shared objects) that I install {CMAKE_PREFIX}/lib/<appname>, how can I find out this path at runtime to load the plugins? Note that the CMAKE_PREFIX user user settable.

If these plugins are part of your application project and you are looking for a build time answer, you can generate a config.h file containing that path.
You can use CMake's configure_file command for that.

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Path to the project current dir in qt

I want to get a path to the project directory in Qt and reference the other files of my project relative to it. I know this issue have been already discussed here
Get current working directory in a Qt application
and here
How to get current working directory path of a Qt application?
but the answer is still unknown. In case it's impossible to get such a path then what is the approach of navigation among files of the Qt project.
Based on your comment, you are trying to:
Access some images which are being used in my program. I could of course put them into build target directory, but it becomes uncomfortable to pass my code to others.
The approach to store resource files in the project source directory and rely on such structure at runtime is not a greatest idea. I can't imagine the situation when mixing the concepts of initially decoupled source and build directories could be useful, correct me if I'm wrong.
So, according to your needs:
The most simple and plain way is to use the Qt resource system. The resource files are simply embedded into the executable, so there will be no need to access the file system.
Another way is the automatic deployment of the needed files. This answer describes the way to copy your files to the target directory using qmake.

How to use a license with JWrapper

So I have been working with the free version of JWrapper for some time now and have been quite pleased with the results; however, I have now purchased a license and would like to use it but I am unable to find the method with which to activate my JWrapper. I do not use the graphical interface version of JWrapper; rather I have created a xml installation file and pass that directly via commandline to JWrapper for building. Is there a special xml tag for specifying the license location? I was unable to find this information on JWrapper's homepage or support docs.
I received an answer from the support team. In order to use the license without using the JWrapperApp gui to build your application you will simply have to have the jwlicense.txt file in the same directory as your jwrapper.jar
After some tests it appears that the jwlicence.txt file must be in the current directory. So the best is to have all the files (jwrapper jar, jwrapper.xml and jwlicence.txt) in the same folder and run the compiler from that folder.

Qt including resource directory structure inside executable

I'm using QWebView to run a web app. There are 650+ files. Placing the web app's directory in the source directory does not result in the executable bundling the directory.
How do I include the entire web app directory so that the executable will be able to render the files.
Note: I have currently added index.html as a resource, and can access it with qrc:// - But since I cannot add the entire directory structure to a qrc (can I?), the executable does not include the other files.
You need to put an XML node into the .qrc file for each file you want to use using the Qt resource system.
This can be done using a simple pre-build script. Take a look at qrcgen. Quoting the blog post behind this link:
The script I created, qrcgen, takes a directory and a prefix, recursively scans the directory and generates a .qrc file with the same name as the directory scanned. It has solved my problem, and I hope it can help others. It is also available via PyPI, just "easy_install qrcgen".
In order to update the .qrc file whenever your directory contens change, you need to include this step into your build process:
For C++/Qt projects, you can add this step in the build configuration in QtCreator or add in your qmake file a system(...) statement. Note that such commands aren't portable in general. (If it's not portable, you can put some operating system conditions around multiple commands.)
For PyQt/PySide projects, I don't know how to do this, but I'm sure you find a solution for this too.

Cannot find correct file called qtnetwork4.dll

Guys I've written app in qt and when trying to run it (double click on *.exe) I'm getting error that this application cannot start because qtnetwork4.dll isn't available. I've searched my drive and I found few files with this name (and copied one by one every time trying to run my app) but none of them seems to work. How can I solve it?
place into your *.exe - folder appropriate dll-s from %QT_PATH%\bin\
There is an app called Dependency Walker that will let you know what functions in qtnetwork4.dll are being used in your program. It can be found at the following:
http://www.dependencywalker.com/
All of the DLLs your program use will be from the same installation as the qmake.exe that is used to compile the program. If you are using Qt Creator you can see where the qmake.exe your using is located by going to:
tools->options->Qt4
Get the DLLs that are located at the path displayed here to make sure they will work with your program.
On windows, DLL are looked for in folder where executable lies, then using "PATH" environenment variable.
In your case, you want to put your dll along your executable, taking them from the sdk you're using to compile
The following page provides a lot of additional information on the subject (example, plugins, strategy for building installers)
To force using QtNetwork and linking it, you have to put
QT += network
in your poject file.
If you're sure you're not using it, you can use
QT -= network

Compiled distribution of Qt application for windows

I was successfully able to compile and run my Qt application. However, when I move the .exe file outside its original path, I found out that I have to manually copy the Qt DLLs (e.g. mingw10.dll, qtcore4.dll). Is there any dynamic way to link these libraries with my application?
I think you mean you want to "statically" link these libraries with your application.
Basically this means that everything will be rolled inside your exe, and you will have no need of those dlls anymore.
There are advantages to to static linking, but there are also disadvantages as well. You should be absolutely sure that this is what you want to do before you go this way.
Check out this link which explains the difference in depth Dynamic Linking vs Static Linking
As for your specific issue, if you are sure you want to use static linking you will have to change your Qt setup to be built statically. By default the Qt distribution is setup to use dynamic linking. There is a handy guide for that here.
Basically when you setup the build you have to run "configure -static" to change all the project settings to use static linking instead of dynamic linking. And then build Qt over again.
You should also verify your Qt license. If you are using the Qt LGPL license and you want to to link statically you will have to include all your object files (.o and .obj) as Mihai Limbășan wisely explained in his comment. If you have bought and paid for Qt, then you have no problem.
If the DLLs are on the PATH for the application, then they will be found and work. So, you could add where your Qt binaries/dlls are into the %PATH% environment variable. If you're going to create an installer for your application, you'll need to either package these libraries in so they're in the bin directory - or you'll have to expect every user to install and possibly compile Qt themselves (hint: go with the first option. :) )

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