解决办法：
加上下面两句关键代码就行：
app:tabBackground="@color/transparent"
app:tabRippleColor="@color/transparent"
完整代码：
<android.support.design.widget.TabLayout
android:id="@+id/typeListTl"
android:layout_width="match_parent"
app:tabMode="scrollable"
app:tabIndicatorColor="#47D7AC"
app:tabTextColor="#73000000"
app:tabSelectedTextColor="#47D7AC"
app:tabBackground="@color/transparent"
app:tabRippleColor="@color/transparent"
android:layout_height="48dp"
android:background="#FFFFFF"/>
