libqpa-mirserver.so does not exist

[Corbin]

I am on Ubuntu Gnome 15.04, and tried to run unity8. Upon running, I get an error that reads:
$ unity8
file:///usr/share/unity8/Shell.qml:21:1: plugin cannot be loaded for module "Unity.Application": Cannot load library /usr/lib/x86_64-linux-gnu/qt5/qml/Unity/Application/libunityapplicationplugin.so: (libqpa-mirserver.so: cannot open shared object file: No such file or directory)
     import Unity.Application 0.1
     ^

[Corbin (crutchcorn)]

Installing unity8-autopilot fixes this, however causes more issues
$ unity8 --mousetouch
QObject: Cannot create children for a parent that is in a different thread.
(Parent is DashCommunicator(0x1ab75b0), parent's thread is QThread(0x17b5840), current thread is DashCommunicator(0x1ab75b0)
ScreenShotter: failed to create directory at: "/home/crutchcorn/Pictures"
Fail to connect with service: QDBusError("org.freedesktop.DBus.Error.ServiceUnknown", "The name com.canonical.pim was not provided by any .service files")
Couldn't find a .desktop file for "dialer-app" . Skipping...
Couldn't find a .desktop file for "messaging-app" . Skipping...
Couldn't find a .desktop file for "address-book-app" . Skipping...
Couldn't find a .desktop file for "com.ubuntu.camera_camera" . Skipping...
Couldn't find a .desktop file for "com.ubuntu.gallery_gallery" . Skipping...
Couldn't find a .desktop file for "webbrowser-app" . Skipping...
Failed to initialize lights hardware.
No lights device
GStreamer; Unable to pause - "file:///system/media/audio/ui/camera_click.ogg"
file:///usr/share/unity8/Shell.qml:114:5: QML QQuickImage: Invalid image data: file:///usr/share/backgrounds/gnome/adwaita-timed.xml
This backend doesn't support multiple users
file:///usr/share/unity8/Launcher/LauncherPanel.qml:522: TypeError: Cannot read property 'width' of undefined
file:///usr/share/unity8/Launcher/LauncherPanel.qml:565: TypeError: Cannot read property 'height' of undefined
Error: "Resource not found."
Session::Session() "unity8-dash"
Application::setSession - appId= "unity8-dash" session= Session(0x38d77f0)
MirSurfaceItem::MirSurfaceItem() "unity8-dash"
MirSurfaceItem::createQmlContentItem()
Session::setSurface - session= "unity8-dash" surface= MirSurfaceItem (this = 0x3dd2450 , name= "" , parent = 0x0 , geometry = QRectF(0,0 320x560) , z = 0 )
Failed to initialize lights hardware.
No lights device
QThread: Destroyed while thread is still running
Session::~Session() "unity8-dash"
Application::setSession - appId= "unity8-dash" session= QObject(0x0)
MirSurfaceItem::~MirSurfaceItem() "unity8-dash"
Session::setSurface - session= "unity8-dash" surface= QQuickItem(0)

[Corbin (crutchcorn)]

Also, what something the above does not have is showing that unity8 does not recognize touch.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Michał Sawicz (saviq)]

Corbin, running unity8 under X11 isn't really useful for anything other than testing. If you install unity8-desktop-session-mir, you can choose the Unity8 session in LightDM and get the full experience.

[Corbin (crutchcorn)]

And I know that, but is this still not a bug?

Also, unity8-desktop-session-mir did not add Unity8 session to LightDM

[Michał Sawicz (saviq)]

No, it's not a bug in the sense that we only require *an* implementation of the Unity.Application module, and the Mir one is preferred, as it's the only real implementation. So installing just unity8 won't get you the fake one that will let you run under X11 - you need to install it manually. We could improve the error message, that's for sure.

As for the missing lightdm session, it's the first I've heard, did you reboot after installing it? Can you please file a bug against unity8-desktop-session for this please?