title: Check if all nodes are expanded - jstree
body: <p>I'm using <a href="https://www.jstree.com/" rel="nofollow noreferrer">jstree</a> library and I'm trying to understand how to check if the tree has all it's nodes expanded after I expand one node. This functionality I want to use in order to set a switch on/off weather all nodes are expanded or all nodes are not expanded.</p>