Hello folks. Let's say i have a method to check internet connection inside my ViewModel that's somet...

# android

[Caio Costa]

Hello folks. Let's say i have a method to check internet connection inside my ViewModel that's something along these lines:

internal fun callToCheckIfInternetConnectionIsAvailable(
onConnectionAvailable: () -> Unit = {},
onConnectionUnavailable: () -> Unit = {}
) {
if(networkChecking.checkIfInternetConnectionIsAvailable()) {
onConnectionAvailable()
} else {
onConnectionUnavailable()
}
}
And then i pass something like this from my Activity:

viewModel.callToCheckIfInternetConnectionIsAvailable({
onConnectionUnavailable = { Toast.makeText(applicationContext, "Bla", Toast.LONG).show() }
})

When it is passed to my ViewModel, it will be interpreted as a method since it's wrapped by a lambda. Although that is true, the content inside that lambda, contains lifecycle-related references such as a View. Could passing this instruction to a ViewModel cause a memory leak if the LifecycleOwner(Activity/Fragment) gets destroyed in the meantime? And besides that, would it break the MVVM pattern? Really curious to know your thoughts on the matter. Thank you in advance K

[Christopher Elías]

As far as the memory leak part, if you want to know that use https://github.com/square/leakcanary and for the MVVM part this.

[Caio Costa]

I already have leak canary installed but it is hard to reproduce the scenario

[Christopher Elías]

Well if you already have leakcanary on your project, it will automatically prompt a notification when a leak has appear.

[Caio Costa]

Unfortunately the article you sent doesn't cover my question. It's kind of a gray area so it's more specific than most cases.

[Saiedmomen]

If the lambda references view, it would crash when if view is destroyed and callback is called.

[Saiedmomen]

It is the same as having none lifecycle aware subscription. It leaks, crashes everything 🙂

[Caio Costa]

Makes sense. Thank you @Saiedmomen 👍

[Scott Kruse]

Maybe consider restructuring your logic flow to avoid this situation.

Instead of passing in a lambda from your view layer risking leak, rather expose a model that encompasses the toast UI state to your livedata from your viewmodel that your view can observe on

[Caio Costa]

Indeed @Scott Kruse. That's exactly what I started to do today. Thanks for the tip 👍

[Scott Kruse]

no prob !