Play a video on qt 5.12 c++

[jsulm]

@AliM93 Did you add

QT += multimedia

to your pro file (see https://doc.qt.io/qt-5/qmediaplayer.html)?

[AliM93]

@jsulm i'm using a cmake file,, not qmake, so i don't have the .pro file. I've tried to add in my cmake script these lines:

find_package(Qt5 COMPONENTS Core Gui Widgets PrintSupport Sql Multimedia)

target_link_libraries(agree_gui ${QT_LIBRARIES} ${catkin_LIBRARIES}
(
Qt5::Multimedia
)

but i got this error:
:-1: error: cannot find -lQt5::Multimedia

[jsulm]

@AliM93 How was Qt installed?

[AliM93]

@jsulm from the terminal

[jsulm]

@AliM93 said in Play a video on qt 5.12 c++:

from the terminal

This doesn't tell much.
Did you use apt to install Qt packages from Ubuntu? If so, did you install libqt5multimedia package?

[AliM93]

This post is deleted!

[AliM93]

in the qt lib i have these libraries : the path is : QtCreator/latest/lib/Qt

• libQt5Multimedia.so.5
• libQt5Multimedia.so.5.12
• libQt5Multimedia.so.5.12.4
• libQt5MultimediaGstTools.so.5 (.12 .12.4)
• libQt5MultimediaQuick.so.5 (.12 .12.4)
• libQt5MultimediaWidgets.so.5 (.12 .12.4)

[SGaist]

Hi,

You did not answer @jsulm's question: how exactly did you install Qt ? Using the Qt Online Installer ? Using your distribution package manager ?

Also how did you install Qt Creator ?

If you installed Qt using the package manager, you have to install the corresponding development packages.

[jsulm]

@AliM93 said in Play a video on qt 5.12 c++:

QtCreator/latest/lib/Qt

This looks like the installation directory of QtCreator which doesn't matter.
Again: how exactly did you install Qt? Did you install Qt packages provided by your distribution (via apt)?
Please answer the questions else nobody will be able to help you.

[Pablo J. Rogina]

@AliM93 said in Play a video on qt 5.12 c++:

:-1: error: cannot find -lQt5::Multimedia

I guess you may need to try a different name for the library...

target_link_libraries(agree_gui ${QT_LIBRARIES} ${catkin_LIBRARIES}
(
Qt5Multimedia
)

[AliM93]

@Pablo-J-Rogina i've tried but same error.

[AliM93]

@jsulm https://ros-qtc-plugin.readthedocs.io/en/latest/_source/How-to-Install-Users.html
i used this link because i need also to install the ros plugin. i followed the bionic online installer

[jsulm]

@AliM93 That link describes how to install QtCreator (not Qt) and a QtCreator plug-in. So, my question is still not answered...

[AliM93]

@jsulm i used this and only this one so maybe i did not install Qt

[SGaist]

Then it's not a maybe, you just have installed Qt Creator.

In any case, are you trying to build a Qt application for ROS or just a Qt application ?

[AliM93]

@SGaist i''m trying to build a qt application for ROS

[SGaist]

Then install Qt.

Where did you get Qt Creator from ?

[AliM93]

@SGaist I got it from the link that i posted. I follow that link and then i installed qt creator with the ROS plugin.
How can i install qt?

I noticed that in my Qt creator folder i have also this path:
QtCreator -> latest -> lib -> Qt --> (...)
may this mean i have also installed Qt? The code i wrote since now works well. is it possible that i installed only Qt Creator without Qt?

Sorry for my bad installation skills.
thank you all.

[jsulm]

@AliM93 said in Play a video on qt 5.12 c++:

QtCreator -> latest -> lib -> Qt --> (...)
may this mean i have also installed Qt?

No, these are Qt libraries used by QtCreator (QtCreator is a Qt application).
"is it possible that i installed only Qt Creator without Qt?" - I think so, as the link you posted only talks about QtCreator installation.

"How can i install qt?" - you can use Qt Online Installer (from official Qt web site). On Linux you can install Qt packages provided by the Linux distribution.

[AliM93]

Thanks.

And may the qt installation change something in my Qt creator application?
Sorry buy i'm terrified by the fact that i cannot use anymore the ROS plugin and so the application i implemented since now.

thanks.