System-Notification

[Buschhardt]

Hello, I see in calibre also a system notification.

How can I use this in Python? A simple example would be nice.

Thank You

[Buschhardt]

Thanks to kovidgoyal

Here is an example

from calibre.gui2 import notify
n = notify.get_notifier()
n('hello', timeout=3000)

[thiago.eec]

I tried it here but couldn't make it work. notify.get_notifier() returns None (either from the command line or from a gui Plugin).

[kovidgoyal]

That means no notification backend was found on your system.

[thiago.eec]

Originally Posted by kovidgoyal

That means no notification backend was found on your system.

I'm on Windows 11. Shouldn't it find one?

[kovidgoyal]

Originally Posted by thiago.eec

I'm on Windows 11. Shouldn't it find one?

On windows notifications are via Qt which in turn relies on the system try which needs a QApplication.

[thiago.eec]

Originally Posted by kovidgoyal

On windows notifications are via Qt which in turn relies on the system try which needs a QApplication.

So, not accessible via plugin, right?

[kovidgoyal]

Originally Posted by thiago.eec

So, not accessible via plugin, right?

Depends if it s GUI plugin yes it should be.

[thiago.eec]

Originally Posted by kovidgoyal

Depends if it s GUI plugin yes it should be.

Well, first I checked if the tray was available and supported messages:

QSystemTrayIcon.isSystemTrayAvailable()
QSystemTrayIcon.supportsMessages()

Both returned 'True'.

Then, I tried to show a message from a GUI plugin:

from calibre.gui2.ui import get_gui
from calibre.gui2 import notify
gui = get_gui()
tray = QSystemTrayIcon(gui)
n = notify.get_notifier(systray=tray)
n('hello', timeout=3000)

It didn't work. No message shown.

1) If I call get_notifier() without the systray argument, then it returns None
2) If instead of get_gui(), I use QApplication.instance(), it doesn't work either

What am I missing?

[kovidgoyal]

Did you enable the system tray icon in calibrepreferences? do notifications from calibre itself work? for example when a conversion is done you will get a notification about it normally.

[thiago.eec]

Originally Posted by kovidgoyal

Did you enable the system tray icon in calibrepreferences? do notifications from calibre itself work? for example when a conversion is done you will get a notification about it normally.

1) Yes. Preferences > Look & feel > Enable system tray icon' is checked and the icon is showing in the tray
2) No. No notification when calibre completes a conversion.

I remember seeing notifications in the Windows notification panel only when I was in debug mode. I've never seen a notification in normal mode.

I my Windows 11 machine, when I check the system config 'System > Notifications', calibre is not listed there. I see many other programs, but not calibre.

[Comfy.n]

I see the taskbar flash upon any job completion, and I'm happy with it by the way.

For instance, in my Waterfox settings I have alerts.useSystemBackend set to false. I don't need every program in the system to be fully integrated to Windows, especially when the browser itself is almost like an OS (I have hundreds of add-ons that provide extended functionality) and send out tons of useful notifications, that I need to monitor.

The other day I tried to make a .bat script reproduce this same behavior Calibre has in my system. Taskbar flashing for that script would be perfectly sufficient because it's not too intrusive. When I realised I would need to use powershell, I put this on hold. (I can only do some basic stuff using windows classic shell)

However, from time to time I miss the ability to see when some task is completed in Calibre. For instance: GR Author Notes plugin.

[thiago.eec]

Originally Posted by Comfy.n

I see the taskbar flash upon any job completion, and I'm happy with it by the way.

Yes, the taskbar icon flashes.

[kovidgoyal]

Originally Posted by thiago.eec

1) Yes. Preferences > Look & feel > Enable system tray icon' is checked and the icon is showing in the tray
2) No. No notification when calibre completes a conversion.

I remember seeing notifications in the Windows notification panel only when I was in debug mode. I've never seen a notification in normal mode.

I my Windows 11 machine, when I check the system config 'System > Notifications', calibre is not listed there. I see many other programs, but not calibre.

It's quite possible the Qt notifications are broken on windows. They probably dont use the new windows 11 notification infrastructure. I havent bothered looking into it since that uses winrt and building stuff against it requires extra dependencies not worth the hassle.

[kovidgoyal]

I tried it on my win11 machine with system tray enabled and notifications on job completion not disabled and I got popup notifications as expected when converting. Though I dont see any system tray anymore in windows. IIRC windows requires shortcuts to be installed for the application otherwise it refuses to show notifications so maybe its caused by using calibre portable.