Android仿iOS网易云音乐viewpager指示器

效果

使用(ConstraintLayout还有些问题...)

```
<!--xml-->
    <com.example.funneteaseindicator.FNI
        android:id="@+id/fni"
        android:layout_marginTop="2dp"
        android:layout_marginBottom="2dp"
        android:layout_width="300dp"
        app:radius_round="24dp"
        app:title_color="@android:color/holo_red_light"
        app:selected_title_color="@android:color/white"
        android:layout_height="45dp"/>

//Java
    viewPager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener{
        override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
            fni.onPagerScrolling(position,positionOffset)
        }
        override fun onPageScrollStateChanged(state: Int) {
        }
        override fun onPageSelected(position: Int) {
        }
    })
```