MVVM-Architecture | The practice of MVVM + Jetpack architecture in Android | Model View Controller library

I'm following this tutorial on using MVVM with Retrofit

https://medium.com/@ronkan26/viewmodel-using-retrofit-mvvm-architecture-f759a0291b49

where the user places MutableLiveData inside the Repository class:

In MVVM we have Activities and Fragments. Fragments and Activities have access to ViewModel. ViewModles have access to Repository. Repository has access to local and online database.

I want to build a Service component so that when the application is put on background the Service should continue to write to the local database.

This is how my application looks like:

https://source.coderefinery.org/Karagoez/mytourassistent

I couldn't find reliable information on how Service are implemented in MVVM architecture.

Should the Service get the viewModel of the Activity it's called from and call repository from that?

Should the Service be defined inside repository?

How should the Service component be implemented in the MVVM architecture when the Service is writing to database?

A similar question is asked there: What is the right place to start a service in MVVM architecture Android

But it get two answers that are quite different from each other.

I am working on a SwiftUI project, where I use the MVVM-architecture.

When changing a View-model object property from the SwiftUI view, it causes a memory conflict crash in the view-model object.

The error is of the type: Simultaneous accesses to 0x600003591b48, but modification requires exclusive access.

In steps, here is what happens:

1. View-model property is changed from view
2. View-model property changes model property
3. Model property notifies about changes
4. View-model receives change notification
5. View-model access model object
6. Crash occur due to memory conflict

Relevant code snippets are seen below. Xcode project is a standard SwiftUI project.

The error will happen, after first clicking the add button, and then the modify button.

If the "update" code is moved into the "receiveValue" closure, the error will not occur. Likewise, the error will not occur, if the View-model class is made non-generic.

To my best knowledge, the code is all-right, so I suspect it is a compiler problem. But I am not sure.

I have a tableView with several cells (created by MVVM-architecture).

In ViewController I fill my tableView like this: