question: void addView ( View child , int index , boolean hidden ) { final int offset ; if ( index < 0 ) { offset = mCallback . getChildCount ( ) ; } else { offset = getOffset ( index ) ; } mCallback . addView ( child , offset ) ; mBucket . insert ( offset , hidden ) ; if ( hidden ) { mHiddenViews . add ( child ) ; } if ( DEBUG ) { Log . d ( TAG , "addViewAt " + index + ",h:" + hidden + ", " + this ) ; } }
target:  Add a view to the ViewGroup at an index