Treeview in DIV

Hi

I am having the Treeview in the div  and that div is Toggling on mouse over

Now I want to Set the Div height to the hight of Treeview and as Treeview expands the div hight should expand and vaiceversa

I was able to do by not setting the height of Div

But When the Treeview was expanded more div crossed the size of page

So i want That the Div should not expand the certain height and if the height of treeview increasse the page height than the scroll should come

and when the height of treeview decrease/collapse the scroll should go

 

Any Code or suggession Plese Thanks in advance
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