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Snackbars

Snackbars

The Snackbar widget provides brief feedback about an operation through a message at the bottom of the screen. Snackbars disappear automatically, either after a timeout or after a user interaction elsewhere on the screen, and 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.

Design & API Documentation

Usage

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 (either as a CharSequence or a resource ID), and a duration to display the snackbar for (either a duration preset, or a time in milliseconds). 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:

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.

Calling make only creates the snackbar, it doesn't actually cause it to be visible on the screen. For showing the snackbar, 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.

Showing a snackbar with just a message and no action would look like this:

// 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.
View contextView = findViewById(R.id.context_view);

Snackbar.make(contextView, R.string.item_removed_message, Snackbar.LENGTH_SHORT)
    .show();

Adding an action

To add an action, use the setAction method on the object returned from make. Actions require both text to display, and an OnClickListener to handle clicks on the action. Snackbars are automatically dismissed when the action is clicked.

Showing a snackbar with a message and an action would look like this:

Snackbar.make(contextView, R.string.item_removed_message, Snackbar.LENGTH_LONG)
    .setAction(R.string.undo, new OnClickListener() {
      @Override
      public void onClick(View v) {
        // Respond to the click, such as by undoing the modification that caused
        // this message to be displayed
      })
    });

Action text color can be customized through the setActionTextColor methods (defaulting to your theme's accent color).

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.