coco
74 lines
2.2 KiB
Markdown
74 lines
2.2 KiB
Markdown
# Coroutines integration
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!!! success
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The `screenModelScope` and `StateScreenModel`are part of the core library.
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### CoroutineScope
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The `ScreenModel` provides a `screenModelScope` property. It's canceled automatically when the `ScreenModel` is disposed.
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```kotlin
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class PostDetailsScreenModel(
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private val repository: PostRepository
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) : ScreenModel {
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fun getPost(id: String) {
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screenModelScope.launch {
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val post = repository.getPost(id)
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// ...
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}
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}
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}
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```
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### State-aware ScreenModel
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If your `ScreenModel` needs to provide a state, use the `StateScreenModel`. Set the initial state on the constructor and use `mutableState` to change the current state.
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```kotlin
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class PostDetailsScreenModel(
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private val repository: PostRepository
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) : StateScreenModel<PostDetailsScreenModel.State>(State.Init) {
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sealed class State {
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object Init : State()
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object Loading : State()
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data class Result(val post: Post) : State()
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}
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fun getPost(id: String) {
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coroutineScope.launch {
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mutableState.value = State.Loading
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mutableState.value = State.Result(post = repository.getPost(id))
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}
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}
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}
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```
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In your screen use `state.collectAsState()` and handle the current state.
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```kotlin
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class PostDetailsScreen : Screen {
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@Composable
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override fun Content() {
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val screenModel = rememberScreenModel<PostDetailsScreenModel>()
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val state by screenModel.state.collectAsState()
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when (state) {
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is State.Loading -> LoadingContent()
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is State.Result -> PostContent(state.post)
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}
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}
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}
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```
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### Sample
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!!! info
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Sample code [here](https://github.com/adrielcafe/voyager/tree/main/samples/android/src/main/java/cafe/adriel/voyager/sample/screenModel).
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### Desktop Note
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!!! info
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If you are targeting Desktop, you should provide the dependency `org.jetbrains.kotlinx:kotlinx-coroutines-swing`, the `screenModelScope` depends on `Dispatchers.Main` provided by this library on Desktop. We don't include it because this library is incompatible with IntelliJ Plugin, [see](https://youtrack.jetbrains.com/issue/IDEA-285839). If you are targeting Desktop for IntelliJ plugins, this library does not require to be provided. |