Why my ftree code is wrong?

Question

this is oracle demo code:
** Built-in: SET_TREE_NODE_PROPERTY
-- This code could be used in a WHEN-TREE-NODE-SELECTED
-- trigger to change the icon of the node clicked on.
DECLARE
htree ITEM;
current_node FTREE.NODE;
find_node FTREE.NODE;
BEGIN
-- Find the tree itself.
htree := Find_Item('tree_block.htree3');
-- Change it icon of the clicked node.
-- The icon file will be located using the
-- UI60_ICON environment variable in client/server
-- or in the virtual directory for web deployment.
Ftree.Set_Tree_Node_Property(htree, :SYSTEM.TRIGGER_NODE, Ftree.NODE_ICON, 'Open');
END;
but when i compile it raise this error?
have too many "set_Tree_Node_Property" description match it

Answer 1

Try this:
DECLARE
htree ITEM;
current_node Ftree.NODE;
find_node Ftree.NODE;
BEGIN
-- Find the tree itself.
htree := Find_Item('tree_block.htree3');
-- Change it icon of the clicked node.
-- The icon file will be located using the
-- TK_ICON environment variable in client/server
-- or in the virtual directory for web deployment.
          current_node := :SYSTEM.TRIGGER_NODE;
Ftree.Set_Tree_Node_Property(htree,
               current_node,
               Ftree.NODE_ICON,
               'Open');
END;
I assume you followed Note 210663.1. This for a reason I don't know seems to be wrong for this part.
Frank