Gets the height of a GTree
If the GTree contains no nodes, the height is 0. If the GTree contains only one root node the height is 1. If the root node has children the height is 2, etc.
the height of tree
Gets the height of a GTree
If the GTree contains no nodes, the height is 0. If the GTree contains only one root node the height is 1. If the root node has children the height is 2, etc.