Disposing resources within viewmodels on shell closing

[SiL3NC3]

How to ensure that dispose function is being called and finished execution for several viewmodels when shell (app) is calling closing event using Prism6?
I was trying to register the closing event in shell code behind file and triggering a pubsub event, which is sadly never been fired within the viewmodels...
Also thinking about doing a timer in shell code, to wait for a specific time before closing the window. But this seems to be "hacky" to me.

Is there a proper way in Prism to achieve a stable disposing of resources within the viewmodels?
Any help appreciated. Thank you.

[sigmarsson]

Did you try for size to enforce the subscribers to remain inside the UI thread ?

_eventAggregator.GetEvent<YourPubSubEvent>().Subscribe(OnReceived, ThreadOption.UIThread);

[SiL3NC3]

Thank you for you reply.
No, not tried this option yet....

I figured out today, that I was subscribing to the pubsub event in the module class, not in the viewmodels.
My idea was to register it module-wide, but the event was never triggered.
But, if it subscribed within the viewmodels it is being fired...

Why is it wrong to do this in the module class?

[sigmarsson]

No, I am leaning into saying the seniors here designed the event broadcast in a way that you can filter events on granularity of VM instances and therefore introduced the Predicate<T> while subscribing.

public virtual SubscriptionToken Subscribe(Action<TPayload> action, Predicate<TPayload> filter);