Android detect position of ViewGroup Child -

so have 2 related questions on viewgroups:

1. is linearlayout , instance of viewgroup? meaning, can call getchildat(index) when using linearlayout?

2. can detect when viewgroup child @ "top" of screen (right below action bar) after scrolling? example, when 3rd child scrolled top

i'm working on app utilizes parallax scrolling , i'm using open source library has custom view linearlayout child , 4 textviews linearlayouts children. in custom view class calling getchildat can't seem find documentation on related linearlayouts wanted check. , want check if 1 of these textviews @ top of screen. clairfication appreciated

question 1 { is linearlayout , instance of viewgroup? meaning, can call getchildat(index) when using linearlayout? }

answer = yes... a viewgroup special view can contain other views (called children.) view group base class layouts , views containers .. linear layout view because extends view, , if contains other sub views called children it's viewgroup.. viewgroup extends view.. meaning yes can call getchildat(index) when using linear layout..

question 2 { can detect when viewgroup child @ "top" of screen (right below action bar)? }.

answer yes , can check z order of children in viewgroup(a view containing other sub views) know position, first child child below actionbar, that's if viewgroup (that linear layout) view content of activity - case right? - yea..

if want documentation on getchildat , viewgroups in general look here ..

hope helps.. let me know that's arising..