Complete state hoisting for SignUp Screen

feature/signup/build.gradle.kts

@@ -4,6 +4,7 @@ plugins {
     alias(libs.plugins.kotlin.compose.compiler)
     alias(libs.plugins.kotlin.serialization)
     alias(libs.plugins.kapt)
+    alias(libs.plugins.parcelable)
 }
 
 android {

feature/signup/src/main/java/nl/jovmit/androiddevs/feature/signup/SignUpViewModel.kt

@@ -1,20 +1,34 @@
 package nl.jovmit.androiddevs.feature.signup
 
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.asStateFlow
-import kotlinx.coroutines.flow.update
+import androidx.lifecycle.SavedStateHandle
+import nl.jovmit.androiddevs.core.view.extensions.update
 import nl.jovmit.androiddevs.feature.signup.state.SignUpScreenState
 
-class SignUpViewModel {
+class SignUpViewModel(
+    private val savedStateHandle: SavedStateHandle
+) {
 
-    private val _screenState = MutableStateFlow(SignUpScreenState())
-    val screenState = _screenState.asStateFlow()
+    val screenState = savedStateHandle.getStateFlow(SIGN_UP, SignUpScreenState())
 
     fun updateEmail(value: String) {
-        _screenState.update { it.copy(email = value) }
+        savedStateHandle.update<SignUpScreenState>(SIGN_UP) {
+            it.copy(email = value)
+        }
     }
 
     fun updatePassword(value: String) {
-        _screenState.update { it.copy(password = value) }
+        savedStateHandle.update<SignUpScreenState>(SIGN_UP) {
+            it.copy(password = value)
+        }
+    }
+
+    fun updateAbout(value: String) {
+        savedStateHandle.update<SignUpScreenState>(SIGN_UP) {
+            it.copy(about = value)
+        }
+    }
+
+    companion object {
+        private const val SIGN_UP = "signUpKey"
     }
 }

feature/signup/src/main/java/nl/jovmit/androiddevs/feature/signup/state/SignUpScreenState.kt

@@ -1,7 +1,11 @@
 package nl.jovmit.androiddevs.feature.signup.state
 
+import android.os.Parcelable
+import kotlinx.parcelize.Parcelize
+
+@Parcelize
 data class SignUpScreenState(
     val email: String = "",
     val password: String = "",
     val about: String = ""
-)
+) : Parcelable

feature/signup/src/test/java/nl/jovmit/androiddevs/feature/signup/SignUpScreenStateTest.kt

@@ -1,16 +1,19 @@
 package nl.jovmit.androiddevs.feature.signup
 
+import androidx.lifecycle.SavedStateHandle
 import com.google.common.truth.Truth.assertThat
 import kotlinx.coroutines.test.runTest
 import nl.jovmit.androiddevs.feature.signup.state.SignUpScreenState
 import org.junit.jupiter.api.Test
 
 class SignUpScreenStateTest {
 
+    private val savedStateHandle = SavedStateHandle()
+
     @Test
     fun `email value updating`() {
         val newEmailValue = "email@"
-        val viewModel = SignUpViewModel()
+        val viewModel = SignUpViewModel(savedStateHandle)
 
         viewModel.updateEmail(newEmailValue)
 
@@ -22,12 +25,24 @@ class SignUpScreenStateTest {
     @Test
     fun `password value updating`() = runTest {
         val newValue = ":irrelevant:"
-        val viewModel = SignUpViewModel()
+        val viewModel = SignUpViewModel(savedStateHandle)
 
         viewModel.updatePassword(newValue)
 
         assertThat(viewModel.screenState.value).isEqualTo(
             SignUpScreenState(password = newValue)
         )
     }
+
+    @Test
+    fun `about value updating`() {
+        val newValue = ":dunno:"
+        val viewModel = SignUpViewModel(savedStateHandle)
+
+        viewModel.updateAbout(newValue)
+
+        assertThat(viewModel.screenState.value).isEqualTo(
+            SignUpScreenState(about = newValue)
+        )
+    }
 }