AddEditTaskState.kt.diff

/* Copyright 2022 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 */

// FRAGMENTS CODE CONSUMING THE EVENT WRAPPER SOLUTION

- class AddEditTaskFragment : Fragment() {
-   override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
-     ...
-     viewModel.snackbarText.observe(
-       lifecycleOwner,
-       Observer { event ->
-         event.getContentIfNotHandled()?.let {
-           showSnackbar(context.getString(it), Snackbar.LENGTH_SHORT)
-         }
-       }
-     )
-   }
- }


// COMPOSE CODE CONSUMING USER MESSAGES AS STATE

// State holder for the AddEditTask composable.
// This class handles AddEditTask's UI elements' state and UI logic.
+ class AddEditTaskState(...) {
+   init {
+     // Listen for snackbar messages
+     viewModel.snackbarText.observe(viewLifecycleOwner) { snackbarMessage ->
+       if (snackbarMessage != null) {
+       // If there's a previous message showing on the screen
+       // stop showing it in favor of the new one to be displayed
+       currentSnackbarJob?.cancel()
+       val snackbarText = context.getString(snackbarMessage)
+       currentSnackbarJob = coroutineScope.launch {
+         scaffoldState.snackbarHostState.showSnackbar(snackbarText)
+         viewModel.snackbarMessageShown()
+       }
+     }
+   }
+ }