What is "AddChild" and "root" and how does it work?

[Deicon]

Hi. I'm a beginner

Looking at some scripts, I saw that "AddChild" and "root" are often used. Is there a publication explaining what "AddChild" and "root" is and how it works? (And if not, someone could explain it to me?)

Thanks.

[Deicon]

Thanks for the answer.
For example, what are these expressions below doing?

self.root = self:AddChild(Widget("root"))

self.hand_inv = self.root:AddChild(Widget("hand_inv"))

[Well-met]

oh, this is for widgets. Ignore my previous post

can't help you there

[penguin0616]

AddChild adds the provided widget as a child. Think of it like adopting the widget and calling it your child?

[Deicon]

Thanks for the answer.
Can you explain step by step what the expression mentioned above does?

[penguin0616]

self.root = self:AddChild(Widget("root"))

self, it references the widget. 
.root, creates a new index.
= assigns the right side into the index.
self, references the widget,
:AddChild, adds the first argument as a widget.
Widget, reference to the base widget element.
("root"), the name of the widget which is the first argument.

self.hand_inv = self.root:AddChild(Widget("hand_inv"))

Same thing as the above, except instead of root and "root" it is hand_inv and "hand_inv", and the child is being added into the previously created widget.

[Deicon]

Thank you very much.