Snackbars & SnackbarHostState
Show transient messages the Material way.
Snackbars & SnackbarHostState is a free Jetpack Compose Academy lesson on CoddyKit. This is lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Jetpack Compose Academy learning path, and your progress syncs across the web and the CoddyKit app. The Jetpack Compose Academy course includes 4 lessons in total.
What Is a Snackbar?
A Snackbar is a brief message that slides up at the bottom, like Message sent, then fades on its own. It informs without blocking the screen. 💬
Snackbar vs Dialog
A dialog demands a response; a Snackbar does not. Reach for it for quick confirmations, not for choices the user must make.
Meet SnackbarHostState
Showing a snackbar is driven by SnackbarHostState. This object holds the queue and gives you the function that triggers a message.
val hostState = remember { SnackbarHostState() }Remember It
Wrap the state in remember so the same SnackbarHostState survives recomposition. A fresh one each frame would lose any pending message.
The snackbarHost Slot
Tell Scaffold where snackbars appear by filling its snackbarHost slot with a SnackbarHost bound to your state.
snackbarHost = { SnackbarHost(hostState) }showSnackbar Is Suspend
The showSnackbar function suspends, because it waits while the message is visible. So you must call it from a coroutine, not directly in a click.
Launch From a Scope
Grab a rememberCoroutineScope and launch showSnackbar inside it. That bridges a normal onClick to the suspend call safely.
scope.launch {
hostState.showSnackbar("Saved")
}Add an Action
Pass an actionLabel to add a button, such as Undo. The call returns a result telling you whether the user tapped that action.
val result = hostState.showSnackbar(
"Deleted", actionLabel = "Undo"
)React to the Result
Check the returned SnackbarResult. If it equals ActionPerformed, run your undo logic; otherwise the snackbar simply dismissed.
if (result == SnackbarResult.ActionPerformed) {
restoreItem()
}Control the Duration
Set how long it lingers with SnackbarDuration: Short, Long, or Indefinite. Use Indefinite only when the message truly needs the user to act.
One Host, Many Messages
A single SnackbarHostState queues messages, showing them one at a time. So share one host per Scaffold rather than creating several.
Quick Check
Why must you launch showSnackbar inside a coroutine scope?
Recap
Remember a SnackbarHostState, wire it into Scaffold's snackbarHost, then launch showSnackbar from a scope. You can finish a polished app shell now. 🎉
Frequently Asked Questions
Is the “Snackbars & SnackbarHostState” lesson free?
Yes — the full text of “Snackbars & SnackbarHostState” is free to read here on the web. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Jetpack Compose Academy course, upgrade to CoddyKit PRO. The Jetpack Compose Academy course includes 4 lessons in total.
What will I learn in “Snackbars & SnackbarHostState”?
Show transient messages the Material way. You practise Jetpack Compose Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Jetpack Compose Academy?
No prior experience is required. Jetpack Compose Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 4 of 4.
How long does the “Snackbars & SnackbarHostState” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Jetpack Compose Academy lesson?
Yes. Every Jetpack Compose Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Scaffold: The Screen Skeleton
- TopAppBar & Action Icons
- Bottom Bars & Floating Action Buttons
- Snackbars & SnackbarHostState