I'm trying to follow a tutorial that suppose to show how to add a floating button and in the tutorial it says to add the attribute android:elevation to the buttons xml like this:
<ImageButton
    android:layout_width="30dp"
    android:layout_height="30dp"
    android:id="@+id/editButton"
    android:layout_gravity="center|right"
    android:clickable="false"
    android:background="@drawable/edit_grey"
    android:layout_marginRight="1dp"
    android:elevation="@dimen/elevation_low"/>
but it dosen't recognize that attribute...i believe it has something to do with my project target or sdk...can somebody help me?