How to get the count of TreeItems in a Tree?

ondesic

ItemList has a function to Get_Item_Count to see how many items are in an ItemList. Is there something silimar to that in a Tree node? Or do I have to Get_Children() and the count how many are returned?

cybereality

I usually use get_child_count()

ondesic

I have tried that. It sounds reasonable, but it doesn't return a correct number. I clean fresh created Tree always returns 6 with get_child_count(). Even after adding TreeItems, it returns 6. Perhaps get_child_count() is returning the internal node count of the nodes that make up the Tree, not the TreeItems?

TwistedTwigleg

A tree should only have a single root, so I think you can do something like this to get the number of children in a TreeItem like the root:

var tree = get_node("Tree")
var treeRoot = tree.get_root()
var treeRootCount = 0

var treeRootChild = treeRoot.get_next()
while (treeRootChild != null):
	treeRootCount += 1
	treeRootChild = treeRootChild.get_next()

print ("There are ", treeRootCount, " children in the tree root")

ondesic

Thank you Twisted. Wish there was an easier way as the Tree node is full of great potential. I did have to make one adjustment to your code. line 5 didn't work for me. I had to use treeRoot.get_children() which is poorly named as it only returns the FIRST TreeItem of treeRoot and not all the children as the name implies.

Megalomaniak

Could it be that you are expecting Node class' get_children() to return the whole tree but it really returns an array of (edit: references to) only the direct children?

cybereality

I've never used a Tree before, but I imagine a while loop that calls get_children() recursively would work.

Kojack

Yep, get_children() is only the first direct child and get_next() finds siblings, not grandchildren.

A recursive count function:

func recursiveCount(item):
	if item==null:
		return 0
	var count = 1
	var child = item.get_children()
	while child!=null:
		count += recursiveCount(child)
		child = child.get_next()
	return count

Call that on your root node and it will count every tree item (including the root). print(recursiveCount(tree.get_root()))

ondesic

A lot of work for a treeItem count. There should just be an internal int that ++ every time you add a TreeItem and -- every time you delete.

TwistedTwigleg

Yeah, the get_children function only returns the first child directly under the TreeItem it's called on, which is not very intuitive. The Tree node probably could use a refactoring to change the names a little, but I think it's been left the way it is for compatibility with old code.

@Kojack said: Yep, get_children() is only the first direct child and get_next() finds siblings, not grandchildren.

A recursive count function:
func recursiveCount(item):
	if item==null:
		return 0
	var count = 1
	var child = item.get_children()
	while child!=null:
		count += recursiveCount(child)
		child = child.get_next()
	return count
Call that on your root node and it will count every tree item (including the root). print(recursiveCount(tree.get_root()))

Awesome, thanks for sharing!