How to get ALL children from a node?

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:bust_in_silhouette: Asked By DigitalDrako

I’m trying to get every child of a node, but the method get_children() only returns the first node. How can I get every child of a node?

Do you mean, that get_children() returns the first level of children, is not recursive.

luislodosm | 2022-12-18 12:33

:bust_in_silhouette: Reply From: deaton64

Hi,
Try this:

for _i in self.get_children():
    print(_i)

No, sadly that still only returns the first child. I’ve heard using get_next() works, but I can’t ever get it to work.

DigitalDrako | 2020-06-13 20:54

What’s the output of this: print(get_child_count ())

deaton64 | 2020-06-13 21:08

To me this returns all the children of the node in the stable version of godot:

for _i in self.get_children ():
     print (_i)

o is referred to grandchildren, etc?

estebanmolca | 2020-06-13 21:10

it prints 1. The children I’m trying to get are all instances of the same scene. Could this be why it’s only returning 1?

DigitalDrako | 2020-06-13 21:10

sounds like it. Add this print(get_parent()) to _ready() It will tell you the parent.
It depends what you want to do, but you could add all of the instances to a a group, such as: add_to_group("nmeships")
Which is what I do for all of my enemy ships. Then to get all of my enemy ships, I do:
var _nmeships = get_tree().get_nodes_in_group("nmeships")

And to loop through them: for _enenmy in _nmeships:

deaton64 | 2020-06-13 21:22

Thats super smart, thanks! I haven’t been using groups in this project, so it’s nice to know when they can be used

DigitalDrako | 2020-06-13 21:24

you’re welcome, I can’t remember where I picked that up from, could have been a Udemy course.

deaton64 | 2020-06-13 21:26

From the Doc:
TreeItem get_children ( )
Returns the TreeItem’s first child item or a null object if there is none.
and
TreeItem get_next ( )
Returns the next TreeItem in the tree or a null object if there is none.

I thought of using
get_children and get_next loop to fetch one by one.
But it seem get_children returns all the children of the node as an array.

VipinArl | 2021-07-25 07:29

1 Like
:bust_in_silhouette: Reply From: Dileeep

I don’t know if there is a built in way to do this. But you can use this…

func get_all_children(in_node,arr:=[]):
arr.push_back(in_node)
for child in in_node.get_children():
	arr = get_all_children(child,arr)
return arr

and call it like…

var all_children = get_all_children(the_node)

“the_node” being the node of which you want to get children of. The returned array will have self included as the first node.
You can make it a static function and put it in a class or singleton so you can call it from anywhere in the project.

This question is two years old and I’ve long solved this problem, but I appreciate your dedication :slight_smile:

DigitalDrako | 2022-07-10 18:35

I take that back! I just found this thread again (after googling the same question), and your answer? Fantastic.

DigitalDrako | 2022-09-20 23:24

3 Likes
:bust_in_silhouette: Reply From: idbrii

Another way to iterate all of the children that isn’t recursive and doesn’t require collecting all nodes before processing is to iterate with a list of nodes that you haven’t processed:

    var waiting := get_children()
    while not waiting.empty():
        var node := waiting.pop_back() as Node
        waiting.append_array(node.get_children())
        print(node) # do something with the node here

Here, I don’t care about the order of the nodes so I use pop_back because it’s more efficient. It traverses the nodes with by always processing a parent before its children.

1 Like

Clever and pretty efficient. Worked better than my own solution. Thanks!