Why do I use pure components but still need fragment dependencies?

Question

I have a problem when using compose, then i found the answer

If you use Compose with Fragments, then you may not have the Fragments dependency where viewModels() is defined.

Adding:

implementation "androidx.fragment:fragment-ktx:1.5.2"

use Compose with Fragments, but I use Pure Compose, Also had this problem. What am I missing? Or is there some connection between fragment and compose?


@AndroidEntryPoint
class MainActivity : ComponentActivity() {

    private val userViewModel: UserViewModel by viewModels()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            Content(userViewModel)
        }
    }
}

@Composable
fun Content(userViewModel: UserViewModel) {

    val lazyArticleItem = userViewModel.list().collectAsLazyPagingItems()

    thread {
        repeat(200) {
            userViewModel.insert(User())
        }
    }

    LazyColumn(verticalArrangement = Arrangement.spacedBy(16.dp)) {
        items(lazyArticleItem) { user ->
            Text("user ${user?.id}")
        }
    }

}

The above is my ui interface code, based on this, I don't think I'm using fragment.

I want to declare my logic. I use Pure Compose instead of Fragment, but actually want to run the code must depend on androidx.fragment:fragment-ktx:1.5.2

score 2 · Accepted Answer · answered Feb 08 '23 at 07:34

It happens because you are using

val userViewModel: UserViewModel by viewModels()

You can access a ViewModel from any composable by calling the viewModel() function.
Use:

val userViewMode : UserViewModel = viewModel()

To use the viewModel() functions, add the androidx.lifecycle:lifecycle-viewmodel-compose:x.x.x

score -1 · Answer 2 · answered Feb 08 '23 at 05:08

In programming, "fragment" and "compose" can refer to two related concepts:

Fragment: In UI design, a fragment is a portion of an activity's UI, which can be reused in multiple activities or combined to form a single activity. It provides a way to modularize the UI and make it more manageable.

Compose: Compose is a modern UI toolkit for Android app development introduced by Google, which allows developers to build and style UI elements using composable functions. It provides a way to create and reuse UI components that can be combined to form a complete app UI.

Both concepts are aimed at making UI design and development more modular, reusable and maintainable.

Hope this helps!

In my opinion, what you say is indeed different between them, but in fact Compose also needs fragment dependencies `androidx.fragment:fragment-ktx:1.5.2` — SageJustus, Feb 08 '23 at 05:41

Why do I use pure components but still need fragment dependencies?

2 Answers2