Snackbar.md

Snackbars

Snackbars provide brief messages about app processes at the bottom of the screen.

Contents

• Using snackbars
• Snackbar
• Theming snackbars

Using snackbars

Before you can use Material snackbars, you need to add a dependency to the Material Components for Android library. For more information, go to the Getting started page.

The Snackbar class provides static make methods to produce a snackbar configured in the desired way. These methods take a View, which will be used to find a suitable ancestor ViewGroup to display the snackbar in, a text string to display, and a duration to display the snackbar for. A suitable ancestor ViewGroup will be either the nearest CoordinatorLayout to the View passed in, or the root DecorView if none could be found.

Available duration presets are:

• LENGTH_INDEFINITE (Show the snackbar until it's either dismissed or another snackbar is shown)
• LENGTH_LONG (Show the snackbar for a long period of time)
• LENGTH_SHORT (Show the snackbar for a short period of time)

Note: Snackbars work best if they are displayed inside of a CoordinatorLayout. CoordinatorLayout allows the snackbar to enable behavior like swipe-to-dismiss, as well as automatically moving widgets like FloatingActionButton.

Making snackbars accessible

Snackbars support content labeling for accessibility and are readable by most screen readers, such as TalkBack. Text rendered in snackbars is automatically provided to accessibility services. Additional content labels are usually unnecessary.

Showing a snackbar

Calling make creates the snackbar, but doesn't cause it to be visible on the screen. To show it, use the show method on the returned Snackbar instance. Note that only one snackbar will be shown at a time. Showing a new snackbar will dismiss any previous ones first.

To show a snackbar with a message and no action:

// The view used to make the snackbar.
// This should be contained within the view hierarchy you want to display the
// snackbar. Generally it can be the view that was interacted with to trigger
// the snackbar, such as a button that was clicked, or a card that was swiped.
val contextView = findViewById<View>(R.id.context_view)

Snackbar.make(contextView, R.string.text_label, Snackbar.LENGTH_SHORT)
    .show()

Adding an action

To add an action, use the setAction method on the object returned from make. Snackbars are automatically dismissed when the action is clicked.

To show a snackbar with a message and an action:

Snackbar.make(contextView, R.string.text_label, Snackbar.LENGTH_LONG)
    .setAction(R.string.action_text) {
        // Responds to click on the action
    }
    .show()

Anchoring a snackbar

By default, Snackbars will be anchored to the bottom edge of their parent view. However, you can use the setAnchorView method to make a Snackbar appear above a specific view within your layout, e.g. a FloatingActionButton.

Snackbar.make(...)
    .setAnchorView(fab)
    ...

This is especially helpful if you would like to place a Snackbar above navigational elements at the bottom of the screen, such as a BottomAppBar or BottomNavigationView.

Related concepts

Temporary bottom bars with other sorts of content layouts can be implemented by subclassing BaseTransientBottomBar.

Android also provides a Toast class with a similar API that can be used for displaying system-level notifications. Generally, snackbars are the preferred mechanism for displaying feedback messages to users, as they can be displayed in the context of the UI where the action occurred. Reserve Toast for cases where this cannot be done.

Snackbar

Snackbars inform users of a process that an app has performed or will perform. They appear temporarily, towards the bottom of the screen. They shouldn’t interrupt the user experience, and they don’t require user input to disappear. They disappear either after a timeout or after a user interaction elsewhere on the screen, but can also be swiped off the screen.

Snackbars can also offer the ability to perform an action, such as undoing an action that was just taken, or retrying an action that had failed.

Snackbars example

API and source code:

• Snackbar
  • Class definition
  • Class source

The following is an example of a snackbar with an action button:

In code:

Snackbar.make(contextView, "Text label", Snackbar.LENGTH_LONG)
    .setAction("Action") {
        // Responds to click on the action
    }
    .show()

Anatomy and key properties

The following is an anatomy diagram of a snackbar:

1. Text label
2. Container
3. Action (optional)

Text label attributes

	Attribute	Related method(s)	Default value
Text label style	N/A	N/A	?attr/snackbarTextViewStyle
Text label	android:text	setText	null
Color	android:textColor	setTextColor	?attr/colorSurface
Typography	android:textAppearance	N/A	?attr/textAppearanceBody2

Container attributes

	Attribute	Related method(s)	Default value
Color	app:backgroundTint	setBackgroundTint setBackgroundTintList	?attr/colorSurface at 80% over ?attr/colorOnSurface
Color overlay alpha	app:backgroundOverlayColorAlpha	N/A	0.8f (ignored if app:backgroundTint is set)
Margin	android:layout_margin	N/A	8dp
Elevation	app:elevation	N/A	6dp
Animation mode	app:animationMode	setAnimationMode getAnimationMode	fade

Action attributes

	Attribute	Related method(s)	Default value
Button style	N/A	N/A	?attr/snackbarButtonStyle
Text color alpha	app:actionTextColorAlpha	N/A	0.5f
Text Color	android:textColor	setTextActionColor	?attr/colorPrimary

Styles

	Theme attribute	Default value
Default style	?attr/snackbarStyle	@style/Widget.MaterialComponents.Snackbar
Action button style	?attr/snackbarButtonStyle	@style/Widget.MaterialComponents.Button.TextButton.Snackbar
Text label style	?attr/snackbarTextViewStyle	@style/Widget.MaterialComponents.Snackbar.TextView

See the full list of styles and attrs.

Theming snackbars

Snackbars support Material Theming and can be customized in terms of color and typography.

Snackbar theming example

API and source code:

• Snackbar
  • Class definition
  • Class source

The following is an example of a snackbar with an action button that uses the Material.io Shrine color theming:

Implementing snackbar theming

Using theme attributes in res/values/styles.xml (themes all snackbars and affects other components):

<style name="Theme.App" parent="Theme.MaterialComponents.*">
    ...
    <item name="colorPrimary">@color/shrine_pink_100</item>
    <item name="colorOnSurface">@color/shrine_pink_900</item>
</style>

or using default style theme attributes, styles and theme overlays (themes all snackbars but does not affect other components):

<style name="Theme.App" parent="Theme.MaterialComponents.*">
    ...
    <item name="snackbarStyle">@style/Widget.App.Snackbar</item>
    <item name="snackbarButtonStyle">@style/Widget.App.SnackbarButton</item>
</style>

<style name="Widget.App.Snackbar" parent="Widget.MaterialComponents.Snackbar">
    <item name="materialThemeOverlay">@style/ThemeOverlay.App.Snackbar</item>
    <item name="actionTextColorAlpha">1</item>
  </style>

<style name="Widget.App.SnackbarButton" parent="Widget.MaterialComponents.Button.TextButton.Snackbar">
    <item name="android:textColor">@color/shrine_pink_100</item>
</style>

<style name="ThemeOverlay.App.Snackbar" parent="">
    <item name="colorPrimary">@color/shrine_pink_100</item>
    <item name="colorOnSurface">@color/shrine_pink_900</item>
</style>

or in code (affects only this snackbar):

Snackbar.make(contextView, "Text label", Snackbar.LENGTH_LONG)
    .setAction("Action") {
        // Responds to click on the action
    }
    .setBackgroundTint(resources.getColor(R.color.backgroundTint))
    .setActionTextColor(resources.getColor(R.color.actionTextColor))
    .show()

and in values/colors.xml:

<color name="backgroundTint">@color/shrine_pink_900</color>
<color name="actionTextColor">@color/shrine_pink_100</color>