How to combine Qt/c++ file with a qml file in one project?

ysing

Hi everybody ,

I'm developing a c++ application using Qt and I'm using Qt quick for the design .The problem that I am facing is that I didn't know how to combine a qml file with a c++ file in the same project I mean how to make the link between them ?

I also want to know haw to apply the signal & slot concept with qml?

Can anybody help me please ?

sierdzio

This is covered thoroughly in "the documentation":http://qt-project.org/doc/qt-5/qtqml-cppintegration-topic.html.

Basically, there are 3 options:

expose C++ class as a QML Singleton
add C++ class as a root context property
implement a QQuickItem or QQuickPaintedItem in C++ and use it in QML

ysing

Ok I will try and I hope I could fix the problem .

Do you yu know why an error occurs when I change the project file name ?

sierdzio

No. Please at least provide the error message here and I will try to help you.

ysing

Ok I actually changed the project file name then when i reopened the project and I pressed run the following errors are displayed :

D9024:unrecoognised source fil type '....%the previous project file name%', object file assumed
D9027:source file '....%the previous project file name%' ignored

C1803:cannot open source file %the previous project file name%' no such file or directory

I Tried the following solutions:

clean->run qmake-> run
the project file name cantained a space I've changed it to another name of one word(without spaces)

but the error persists

sierdzio

Probably a session problem. Please do this:

Exit Qt Creator

Browse to where your project is located

Delete <your project name>.pro.user

Start Qt Creator again

Open your project anew

ysing

Thanks sierdzio that worked very well !!

but can you explain for me how did you know that it is a session problem ?

sierdzio

It was an educated guess. Qt Creator uses .pro.user files to store local configuration of the project. If you change the name of the pro file wihtout setting up a new session, that file will hold corrupted session info.

ysing

Ok , Thank you for the clarification.