The 'Findnode' method

Argument: Character vector or two-element nested vector
Result: Integer scalar or vector vector

Valid for: Tree

The Findnode method return the node identifier (or a vector of IDs) for nodes matching the specified characteristic. The first argument is a character vector giving the operation name. Some forms require a second (integer) argument, the node ID. The result is usually an integer scalar node ID, or 0 if none is found. For the 'children' operation, a vector of IDs is returned.

Operations which do not require a second argument are:

'root'           The first top-level node
'firstvisible'   The first visible node
'drop'           The current drag-and-drop target
'select'         The currently-selected node

Operations which do require a second argument, a node ID, are:

'children'       All children of specified node (a vector is returned)
'parent'         Parent of specified node
'child'          First child of specified node
'next'           Next sibling of specified node
'prev'           Previous sibling of specified node
'nextvisible'    Next visible node after the specified node
'prevvisible'    Previous visible node before the specified node