UINavMenuOnMenuItemClick 委托

public delegate void OnMenuItemClick(
	TreeNode node,
	NavMenuItem item,
	int pageIndex
)

Public Delegate Sub OnMenuItemClick ( 
	node As TreeNode,
	item As NavMenuItem,
	pageIndex As Integer
)

type OnMenuItemClick = 
    delegate of 
        node : TreeNode * 
        item : NavMenuItem * 
        pageIndex : int -> unit