Can somebody help me with the code, Navigating Tree in Flex and displaying dynamic pages for each node on the right side of the panel.

Hi,
Im answering your post assuming that the tree is not dynamic.
The idea here is you have a viewstack with some children and a tree to the
left, depending on the selected tree item a child of viewstack is shown. Here
is the code to seleect the child of viewstack to be displayed on click of an
item in the tree.