Delegate and Inject ErrorMonitor

app/src/main/kotlin/com/google/samples/apps/nowinandroid/ui/NiaApp.kt

@@ -96,7 +96,7 @@ fun NiaApp(
             val snackbarHostState = remember { SnackbarHostState() }
 
             val isOffline by appState.isOffline.collectAsStateWithLifecycle()
-            val errorMessage by appState.errorMessage.collectAsStateWithLifecycle()
+            val snackbarMessage by appState.snackbarMessage.collectAsStateWithLifecycle()
 
             // If user is not connected to the internet show a snack bar to inform them.
             val notConnectedMessage = stringResource(R.string.not_connected)
@@ -108,8 +108,8 @@ fun NiaApp(
                     )
                 }
             }
-            LaunchedEffect(errorMessage) {
+            LaunchedEffect(snackbarMessage) {
-                errorMessage?.let {
+                snackbarMessage?.let {
                     val snackBarResult = snackbarHostState.showSnackbar(
                         message = it.message,
                         actionLabel = "Continue",

app/src/main/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppState.kt

@@ -89,7 +89,7 @@ class NiaAppState(
     errorMonitor: ErrorMonitor,
     userNewsResourceRepository: UserNewsResourceRepository,
     timeZoneMonitor: TimeZoneMonitor,
-) {
+) : ErrorMonitor by errorMonitor {
     val currentDestination: NavDestination?
         @Composable get() = navController
             .currentBackStackEntryAsState().value?.destination
@@ -110,7 +110,7 @@ class NiaAppState(
             initialValue = false,
         )
 
-    val errorMessage = errorMonitor.errorMessage.stateIn(
+    val snackbarMessage = errorMessage.stateIn(
         scope = coroutineScope,
         started = SharingStarted.WhileSubscribed(5_000),
         initialValue = null,

core/data/src/main/kotlin/com/google/samples/apps/nowinandroid/core/data/util/ErrorMonitor.kt

@@ -25,4 +25,4 @@ interface ErrorMonitor {
     fun addErrorMessage(error: String): String?
     fun clearErrorMessage(id: String)
     val errorMessage: Flow<ErrorMessage?>
-}
+}

core/data/src/main/kotlin/com/google/samples/apps/nowinandroid/core/data/util/SnackbarErrorMonitor.kt

@@ -21,12 +21,13 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.update
 import java.util.UUID
+import javax.inject.Inject
 
 /**
  * Interface implementation for handling general errors.
  */
 
-class SnackbarErrorMonitor : ErrorMonitor {
+class SnackbarErrorMonitor @Inject constructor() : ErrorMonitor {
     /**
      * List of [ErrorMessage] to be shown to the user, via Snackbar.
      */
@@ -68,4 +69,4 @@ class SnackbarErrorMonitor : ErrorMonitor {
 data class ErrorMessage(
     val message: String,
     val id: String = UUID.randomUUID().toString(),
-)
+)