Problem with ExpandableListView position

Question

I have a "Dynamic" ExpandableListView. That is to say child are only load when there is click on there parent.

So I use onGroupExpand to load list. It works but I must expand myself the group with

expandableList.expandGroup(groupPosition);

The problem is that, when I click on parent, the group expands but the view go back to the first position. That is to say : I scroll, I click on parent, group expand, view go back to the first parent, so I must scroll again to see the group I click before.

I try to use expandableList.scrollTo(x,y); But it doesn't work.