IssueTracker

Confirmed. I can only recreate on API 16 though.

Workaround for now is to set app:borderWidth="0dp"

app:borderWidth="0dp" also fixes elevation issues on 21+.  Without it, no matter how much elevation is specified the FAB is flat.

  <android.support.design.widget.FloatingActionButton
        xmlns:app="http://schemas.android.com/apk/res-auto"
        app:borderWidth="0dp"
        android:id="@+id/fab_1"
        android:layout_marginBottom="16dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal|bottom"
        android:src="@drawable/abc_ic_clear_mtrl_alpha"/>

And i still get a square on lollipop devices

testes on nexus 5 os version 5.1

Fixed internally. Will be out soon.

please release bugfixed version , we need that.

Any news on this?

For those that still have a square button after adding app:borderWidth="0dp", I found that setting android:background was causing the issue for me. Set android:backgroundTint instead.

[Comment deleted]

For those whom nothing else worked, this is the xml layout I used in the end and worked like a charm among all the devices I used:
<android.support.design.widget.FloatingActionButton
        android:id="@+id/ddd"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginBottom="10dp"
        android:layout_marginRight="10dp"
        app:elevation="@dimen/floating_button_elevation"
        app:borderWidth="0dp"
        app:rippleColor="@color/red"
        app:backgroundTint="@color/blue" />
Notice the "app:backgroundTint" instead of "android:backgroundTint"

Hope it helps!

Any Update?

In my case after adding app:borderWidth="0dp" still button was square. Because before using this newly released support lib, i used google android sample in which i end up creating "fab_background" file which was causing this issue. After removing said file button is appearing as circle.

Released in v22.2.1.

FAB still seems to be square in API 16 after new release.

#17: are you changing the FAB's background?

FAB is still square on lollipop devices, i noticed that setting borderWidth to a greater value doesn't exactly fix things but reduces the square drawables size so it resides inside the circular view but is easily distinguished and without giving borderWidth the drawable takes up the whole width and height available to it. Is there a problem with how CircularDrawableForLollipop is implemented??

This seems to still be an issue. Im using support libs 23.0.0, setting app:backgroundTint seems to work as a workaround, has a cause been found for this?