RatioFrameLayout is not rounding its corner from bottom

[FazalHussain]

I have added RationFrameLayout but it is not rounding from bottom

        <net.soulwolf.widget.ratiolayout.widget.RatioFrameLayout
            android:layout_width="@dimen/_40sdp"
            android:layout_height="@dimen/_40sdp"
            android:visibility="gone"
            tools:visibility="visible"
            app:cardCornerRadius="4dp"
            app:cardElevation="4dp"
            app:datumRatio="datumAuto"
            app:layoutAspectRatio="1.0" />