/
BaseComponents.kt
67 lines (50 loc) · 1.8 KB
/
BaseComponents.kt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
package com.codingtroops.composesample.base
import androidx.compose.runtime.MutableState
import androidx.compose.runtime.State
import androidx.compose.runtime.mutableStateOf
import androidx.lifecycle.ViewModel
import androidx.lifecycle.viewModelScope
import kotlinx.coroutines.channels.Channel
import kotlinx.coroutines.flow.*
import kotlinx.coroutines.launch
const val LAUNCH_LISTEN_FOR_EFFECTS = "launch-listen-to-effects"
abstract class ViewState(var isLoading: Boolean = false) {
fun <State : ViewState> State.setIsLoading(value: Boolean): State {
isLoading = value
return this
}
}
interface ViewEvent
interface ViewSideEffect
abstract class BaseViewModel<Event : ViewEvent, UiState : ViewState, Effect : ViewSideEffect> :
ViewModel() {
private val initialState: UiState by lazy { setInitialState() }
abstract fun setInitialState(): UiState
private val _viewState: MutableState<UiState> = mutableStateOf(initialState)
val viewState: State<UiState> = _viewState
private val _event: MutableSharedFlow<Event> = MutableSharedFlow()
private val _effect: Channel<Effect> = Channel()
val effect = _effect.receiveAsFlow()
init {
subscribeToEvents()
}
fun setEvent(event: Event) {
viewModelScope.launch { _event.emit(event) }
}
protected fun setState(reducer: UiState.() -> UiState) {
val newState = viewState.value.reducer()
_viewState.value = newState
}
private fun subscribeToEvents() {
viewModelScope.launch {
_event.collect {
handleEvents(it)
}
}
}
abstract fun handleEvents(event: Event)
protected fun setEffect(builder: () -> Effect) {
val effectValue = builder()
viewModelScope.launch { _effect.send(effectValue) }
}
}