I am wondering if following approach is okay or it...

# compose

[Shahzad Ansari]

I am wondering if following approach is okay or it will become a problem down the line. I have been using this approach where I setup an empty companion object in my data models and define an extension property to get a sample for that data model lazily.

data class User(val name: String, val age: Int) {
    companion object
}

val User.Companion.mock by lazy { User(name = "John", age = 25) }

And I use this mock property to get sample data for my @Preview in Jetpack Compose. Since code defined in @Preview composable does not become part of live app or APK, I am wondering if it's okay to use this approach.

@Preview
@Composable
fun UserInfo() {
    Text(User.mock.toString())
}

[Stylianos Gakis]

If it works for you why not?
Might be a bit confusing/annoying to get the mock appear in autocomplete sometimes, but the alternatives aren't all that good either tbh

[Shahzad Ansari]

Just curious if it's going to cause some performance issues because we are just starting with this approach and heavily creating Previews for our UI components.

[Stylianos Gakis]

Performance of what?

[Shahzad Ansari]

The app itself. Maybe we could run into a case where user has a very low end phone with limited memory and our app might be consuming too much already.

[Stylianos Gakis]

Previews are not used from production code though, why would a function which creates an object which is not even used in the production app have an effect?
You can make it a function instead of a lazy val if you are super concerned , but I would expect r8 to strip those out anyway

[Shahzad Ansari]

fun sounds safer. Thanks 👍