I have worked on your problem and came out with a solution. I have made us of the answer here. I have modified the code little bit and have achieved your goal. Here is the link to my project,
https://github.com/AndroSelva/Vertical-SeekBar-Android
Just a little modification in the onDraw(),
protected void onDraw(Canvas c) {
c.rotate(90);
c.translate(0, -getWidth());
super.onDraw(c);
}
and onTouchEvent(),
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_UP:
int i=0;
i=getMax() - (int) (getMax() * event.getY() / getHeight());
setProgress(100-i);
Log.i("Progress",getProgress()+"");
onSizeChanged(getWidth(), getHeight(), 0, 0);
break;
case MotionEvent.ACTION_CANCEL:
break;
}