Different QT Versions and Packages on Ubuntu 20.04

DQT20

Hi all,

I install QT on Ubuntu 20.04 with these commands:

sudo apt install build-essential
sudo apt install qtcreator
sudo apt install qt5-default

It installed Qt 5.12.8 as default.
And then i installed necessary packages like gstreamer with this command.

sudo apt-get install libgstreamer1.0-0 gstreamer1.0-plugins-base gstreamer1.0-plugins-good 
gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-doc 
gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 
gstreamer1.0-qt5 gstreamer1.0-pulseaudio

Up to this point everything has been okey.

The problem is about another QT Version. I want to install QT 5.15.2 on Ubuntu 20.04.
I install QT 5.15.2 with Online Installer and i can see and choose it in QT Creator.

But the system still recognizes version QT 5.12.8 by default. I can't install gstreamer for QT 5.15.2.

How can i fix this?

jsulm

@DQT20 said in Different QT Versions and Packages on Ubuntu 20.04:

But the system still recognizes version QT 5.12.8 by default

What system? Please explain what you mean.
"I can't install gstreamer for QT 5.15.2" - you already installed gstreamer, it should work. If it does not work please explain what exactly happens.

DQT20

@jsulm said in Different QT Versions and Packages on Ubuntu 20.04:

"I can't install gstreamer for QT 5.15.2" - you already installed gstreamer, it should work. If it does not work please explain what exactly happens.

I can work with gstreamer on QT 5.12.8. But, when i choose QT 5.15.2, i can't work with gstreamer.
Can QT 5.15.2 automatically see gstreamer packages?

JKSH

@DQT20 said in Different QT Versions and Packages on Ubuntu 20.04:

when i choose QT 5.15.2, i can't work with gstreamer.

Why not? What errors do you get?

DQT20

@JKSH

QT can't find libraries.

When selected QT 5.12.8, cpp file can include libraries like:

#include <QGst/Message>
#include <QGst/Sample>
#include <QGst/Buffer>
...

When selected QT 5.15.2, cpp file can't include these libraries.

JKSH

@DQT20 said in Different QT Versions and Packages on Ubuntu 20.04:

QT can't find libraries.

When selected QT 5.12.8, cpp file can include libraries like:
#include <QGst/Message>
#include <QGst/Sample>
#include <QGst/Buffer>
...
When selected QT 5.15.2, cpp file can't include these libraries.

Those are not part of Qt, and they are not part of GStreamer.

They are part of the 3rd-party QtGStreamer bindings library: https://gstreamer.freedesktop.org/bindings/qt.html

I don't know if they are compatible with Qt 5.15 or not. If they are, you can simply tell your project where to find the headers and libraries (for example, if you're using qmake, then add QtGStreamer to your INCLUDEPATH and LIBS variables).

However, if they're not compatible with Qt 5.15, then download the QtGStreamer source code and use Qt 5.15 to build the libraries.