StateMachineを理解しよう

Transcript

1. 4UBUF.BDIJOFΛཧղ͠Α͏ _
   
   4UBUF'MPX Λఴ͑ͯ _
2. 4UBUF'MPX ࢖ͬͯ·͔͢ʁ
3. 4UBUF'MPX ࢖ͬͯ·͔͢ʁ -JWF%BUB
4. 4UBUF.BDIJOF ஌ͬͯ·͔͢ʁ
5. ࠓ೔ͷΰʔϧ 4UBUF.BDIJOF ΛҰݴͰઆ໌Ͱ͖ΔΑ͏ʹͳΔ
6. ஫ҙࣄ߲ งғؾΛ௫ΜͰ΋Β͏ -5
   Ͱ͢ɻ
7. @Composable fun TestScreen() { var age by remember { mutableStateOf(“”) } Column(…) { TextField( value = age, onValueChange = { it -> age = it }, ) Text( text = age ) } }
8. @Composable fun TestScreen( viewModel: TestViewModel = viewModel() ) { val age by viewModel.text.collectAsState() Column(…) { TextField( value = age, onValueChange = { it -> viewModel.updateAge( it ) }, ) Text( text = age ) } } class TestViewModel : ViewModel() { private val _age.MutableStateFlow (””) val age : StateFlow<String> = _age fun updateAge( newAge : String ) { _age.value = newAge } }
9. @Composable fun TestScreen( viewModel: TestViewModel = viewModel() ) { val age by viewModel.text.collectAsState() Column(…) { TextField( value = age, onValueChange = { it -> viewModel.updateAge( it ) }, ) Text( text = age ) } } class TestViewModel : ViewModel() { private val _age.MutableStateFlow (””) val age : StateFlow<String> = _age fun updateAge( newAge : String ) { _age.value = newAge } } 4UBUF
   
   ஋ͷঢ়ଶ
10. ຊདྷͳΒ͹ɾɾ খֶੜ தֶੜ ߴߍੜ ࣾձਓ খֶੜ༻ ϖʔδ தֶੜ༻ ϖʔδ ߴߍੜ༻ ϖʔδ ࣾձਓ༻ ϖʔδ
11. ຊདྷͳΒ͹ɾɾ খֶੜ தֶੜ ߴߍੜ ࣾձਓ খֶੜ༻ ϖʔδ தֶੜ༻ ϖʔδ ߴߍੜ༻ ϖʔδ ࣾձਓ༻ ϖʔδ ը໘ͷঢ়ଶ
12. ը໘ͷঢ়ଶ ஋ͷঢ়ଶ
13. 4UBUF
    .BDIJOF
14. Πϕϯτ ը໘ͷঢ়ଶʹม׵ ϩδοΫ
15. Enum class PersonState { ELEMENTARY, MIDDLE, HIGH, ADULT, NONE }
16. Enum class PersonState { ELEMENTARY, MIDDLE, HIGH, ADULT, NONE } fun getPersonState(age: Int) : PersonState { return when (age) { in 6..12 -> PersonState.ELEMENTARY in 13..15 -> PersonSate.MIDDLE in 16..18 -> PersonState.HIGH in 19..120 -> PersonState.ADULT else -> PersonState.NONE } }
17. class TestViewModel : ViewModel() { private val _age.MutableStateFlow (””) + private val _showInput.MutableStateFlow (true) val age : StateFlow<String> = _age + val showInput : StateFlow<Boolean> = _showInput + private val _state.MutableStateFlow (PersonState.NONE) + val state : StateFlow<PersonState> = _state fun updateAge( newAge : String ) { _age.value = newAge + val age = newAge.toInt() + _state.value = getPersonState(age) + _showInput.value = (state.value == PersonState.NONE) } }
18. @Composable fun TestScreen( viewModel: TestViewModel = viewModel() ) { val age by viewModel.text.collectAsState() + val showInput by viewModel.showInput.collectAsState() Column(…) { + if ( showInput ) { TextField( value = age, onValueChange = { it -> viewModel.updateAge( it ) }, ) + } Text( text = age ) } }
19. ೥ྸΛೖྗ
20. ຊདྷͳΒ͹ɾɾ ˠ Enum class PersonState { ELEMENTARY, MIDDLE, HIGH, ADULT, NONE } Enum class PersonState { Idle, Loading, Success, Error, }
21. ͨ͜ ৘ใ޻ֶՊ೥  ΧϯϑΝϨϯε८ΓʹϋϚͬͯ·͢  ࠷ۙΞ΢τϓοτෆ଍Ͱ͢ɻ "OESPJE
    ΧϯϑΝϨϯε ΞʔΩςΫνϟ !NPOBLB@