VerticalSeekBar

This is a custom vertical seek bar that works with Marshmallow operating system
See http://stackoverflow.com/questions/33112277/android-6-0-marshmallow-stops-showing-vertical-seekbar-thumb

Usage:

<com.verticalseekbar.VerticalSeekBar
  android:layout_width="25dp"
  android:layout_height="match_parent"
  android:splitTrack="false"
  android:thumb="@android:color/transparent"
  app:customThumb="@drawable/thumb" />

You need to ensure that the default android:thumb is transparent so there aren't duplicate thumbs. Use the app:customThumb attribute to define the seek bar's thumb