<Button
        android:id="@+id/expandableButton1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/btn_spravka"
        android:drawableRight="@drawable/ic_plus_1"
        android:paddingRight="10dp"
        android:text="Справочник"
        android:textColor="#fff"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="1dp" />

setCompoundDrawables();