I am passing SessionManager as Dependency that require context in my ViewModel

val viewModel = ViewModelProvider(this, ListingsViewModelFactory(
        ListingsModel(1),
        SessionManager(
            requireContext(), <===== HERE
            JsonEncoder(),
            JsonDecoder()),
        Validator(),
        WebService(),
        JsonEncoder(),
        JsonDecoder()
    )
    ).get(ListingsViewModel::class.java)

we know that passing context to ViewModel is a bad practice that should cause memory leaks.

1. So can we pass context in dependency in ViewModel like currently i'm passing in SessionManager?
2. Passing context in Dependency in ViewModel cause memory leaks?

Thanks for all the answers.

CodePudding user response：

When you call requireContext() in a Fragment, it is actually getting the Activity instance, and passing that to the ViewModel will leak the Activity.

It is safe to pass the application Context, because that is a single instance for the lifetime of your application.

So replace requireContext() with requireContext().applicationContext, and it is fine.

It seems a bit odd that you are instantiating your JsonEncoder and Decoder twice, but maybe it's OK with your logic. You might want to check that.

CodePudding user response：

I assume it depends on the type of context. Since the lifetime of a ViewModel is longer than the lifetime of the view it refers to, passing Activity can cause memory leak.

However, the lifetime of a ViewModel cannot be longer than the lifetime of the application. So the passing of Application should be fine.