Unable to get Metadata PropertiesChanged of org.mpris.MediaPlayer2.Player about bluez-dbus

[hypfvieh]

First: this is not related to bluez-dbus because the mpris stuff has nothing to do with bluetooth or bluez.

I assume you are not listening to the correct dbus bus.
Bluez is usually found on system bus, while most of the things happening in user context is on session bus.
The sample you referenced uses the system bus only to catch properties changed events issued by/for bluez related actions.
As I don't have the mpris stuff on my Ubuntu machine, I cannot check, but I would check if the desired information is found on session bus.

[moontide]

First: this is not related to bluez-dbus because the mpris stuff has nothing to do with bluetooth or bluez.

I assume you are not listening to the correct dbus bus. Bluez is usually found on system bus, while most of the things happening in user context is on session bus.

Sorry, I'm pretty new to dbus, didn't know there's system bus and there's session bus.

The sample you referenced uses the system bus only to catch properties changed events issued by/for bluez related actions.

I added the code before the filtering-out-bluez code, I can see information about org.freedesktop.NetworkManager or org.freedesktop.systemd1.Service been printed, but no Metadata information of org.mpris.MediaPlayer2.Player. So I guess your assumption could be right. But I do see PlaybackStatus information of org.mpris.MediaPlayer2.Player, could firefox send these two information to different bus?

As I don't have the mpris stuff on my Ubuntu machine, I cannot check, but I would check if the desired information is found on session bus.

The mpris interface stuff seems been implemented in firefox 75 already. I also tested Audacious media player, I also see information about org.mpris.MediaPlayer2.Player in dbus-monitor command ouput.

[hypfvieh]

Firefox does not provide mpris on my machine, nothing to see in d-feet on system or session bus.
When starting audacious, I can see the mpris stuff in the audacious process on session bus org.mpris.MediaPlayer2.audacious.
So it looks like you have to add a listener to the session bus.

[moontide]

Firefox does not provide mpris on my machine, nothing to see in d-feet on system or session bus.

I guess you need visit a URL contains media content (say, youtube), and play it.

So it looks like you have to add a listener to the session bus.

Yes, you're totally correct. I test it today, and I got the Metadata information as expected from session bus.