Simple handle problem (I think)

Hi, I'm having trouble understanding how to use handles but I understand the basic principle so I know I should be using them for what I do. I want to make links between 2 objects of the same class. Here is an exemple.

class classA
properties
   val1 = classB.empty;
   val2 = [0,0];

%here the variable I should probably use handle.
   links = classA.empty;
end

%here is how I use it in a script or function :
obj1 = classA;
obj2 = classA;
%I add obj2 to the list of links obj1 is doing and vice versa:
obj1.links=[obj1.links,obj2];
obj2.links=[obj2.links,obj1];

I guess links could be an object type handle but I have no clue how I should write it, and how to set it.

Answer 1

[Sebastian Castro]

This should work, with the exception that classes in MATLAB are by default "value classes". This means that when you say

obj1.links=[obj1.links,obj2];

and then refer to obj1.links(1) (assuming it was previously empty), you're actually referring to a copy of obj2 instead of obj2 itself.

To declare a class as a handle class, i.e., passed by reference, change the first line of your class definition to inherit from the handle superclass:

classdef classA < handle

https://www.mathworks.com/help/matlab/handle-classes.html

- Sebastian

[Marc-Olivier Labrecque-Goulet]

So, that mean I can change properties values of obj2 by calling obj1.links(1)? wow I wasnt expecting that to be that easy!