add

adds a new item to the tree

string add(object obj, [number index,string parentId] );

obj	object	the item object
index	number	optional, the position that the item will be added to (zero-based numbering)
parentId	string	optional, the parent id

string

ID of the newly added item

//inserts a new item into the branch with id='root'
tree.data.add({id:"item10", value:"NewItem"}, 0, "root" );