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Floating Action Buttons

A FloatingActionButton displays the primary action in an application. It is a round icon button that's elevated above other page content. Floating action buttons come in a default and mini size.

Floating action buttons provide quick access to important or common actions within an app. They have a variety of uses, including:

  • Performing a common action, such as starting a new email in a mail app.
  • Displaying additional related actions.
  • Update or transforming into other UI elements on the screen.

Floating action buttons adjust their position and visibility in response to other UI elements on the screen.

Design & API Documentation

Usage

The FloatingActionButton widget provides a complete implementation of Material Design's floating action button component. Here's how to include the widget in your layout:

<androidx.coordinatorlayout.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

  <!-- Main content -->

  <com.google.android.material.floatingactionbutton.FloatingActionButton
      android:id="@+id/floating_action_button"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="bottom|right"
      android:layout_margin="16dp"
      app:srcCompat="@drawable/ic_plus_24"/>

</androidx.coordinatorlayout.widget.CoordinatorLayout>

Note: If the FloatingActionButton is a child of a CoordinatorLayout, you get certain behaviors for free. It will automatically shift so that any displayed Snackbars do not cover it, and will automatially hide when covered by an AppBarLayout or BottomSheetBehavior.

Material Styles

Using FloatingActionButton with an updated Material theme (Theme.MaterialComponents) will provide the correct updated Material styles to your floating action buttons by default. If you need to use an updated Material floating action button and your application theme does not inherit from an updated Material theme, you can apply one of the updated Material styles directly to your widget in XML.

Updated Material Style

The updated Material FloatingActionButton style consists of updated elevation, ripple, and motion changes.

<com.google.android.material.floatingactionbutton.FloatingActionButton
    android:id="@+id/floating_action_button"
    style="@style/Widget.MaterialComponents.FloatingActionButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|right"
    android:layout_margin="16dp"
    app:srcCompat="@drawable/ic_plus_24"/>

Legacy Material Style

<com.google.android.material.floatingactionbutton.FloatingActionButton
    android:id="@+id/floating_action_button"
    style="@style/Widget.Design.FloatingActionButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|right"
    android:layout_margin="16dp"
    app:srcCompat="@drawable/ic_plus_24"/>

Attributes

Feature Relevant attributes
Icon app:srcCompat
app:tint
app:maxImageSize
Size app:fabSize
app:fabCustomSize
Background app:backgroundTint
Ripple app:rippleColor
Border app:borderWidth
Elevation app:elevation
app:hoveredFocusedTranslationZ
app:pressedTranslationZ
Motion app:showMotionSpec
app:hideMotionSpec

Theme Attribute Mapping

Updated Material Style

style="@style/Widget.MaterialComponents.FloatingActionButton"
Component Attribute Default Theme Attribute Value
backgroundTint colorSecondary
tint colorOnSecondary
rippleColor colorOnSecondary

Legacy Material Style

style="@style/Widget.Design.FloatingActionButton"

The legacy Material style of FloatingActionButton does not make use of our new color theming attributes.

Handling Clicks

FloatingActionButton handles clicks in the same way as all views:

FloatingActionButton floatingActionButton =
    (FloatingActionButton) findViewById(R.id.floating_action_button);

floatingActionButton.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View view) {
        // Handle the click.
    }
});

Visibility

Use the show and hide methods to animate the visibility of a FloatingActionButton. The show animation grows the widget and fades it in, while the hide animation shrinks the widget and fades it out.

Sizing

The FloatingActionButton can be sized either by using the discrete sizing modes or a totally custom size.

Sizing Modes

The supported sizing modes are as follows:

  • normal - the normal sized button, 56dp.
  • mini - the mini sized button, 40dp.
  • auto - the button size will change based on the window size. For small sized windows (largest screen dimension < 470dp) this will select a mini sized button, and for larger sized windows it will select a normal sized button.

By default, the sizing mode will be auto, but this can be adjusted via the app:fabSize attribute or the FloatingActionButton#setSize method.

Custom Size

To set a custom size for your FloatingActionButton, you can use the app:fabCustomSize attribute or the FloatingActionButton#setCustomSize method.

If you've set a custom size and would like to clear it, you can call the FloatingActionButton#clearCustomSize method. If called, custom sizing will not be used and the size will be calculated based on the value set using FloatingActionButton#setSize or the app:fabSize attribute.

Related Concepts