<?xml version="1.0" encoding="UTF-8"?>
<section>
    <title>Tree model</title>
    <para>Two classes handle the model: <classname>TreeV3</classname> is "tree" itself and somewhat a root node, while
    <classname>TreeNodeV3</classname> is any  other node, linked by <methodname>parent</methodname>
    and <methodname>children[]</methodname> properties. There is a common mixin <classname>TreeWithNode</classname>.
    </para>
    
    <section>
        <title>Tree parameters</title>
        
        <para><methodname>listeners</methodname> specifies a list of widgetIds.
            They will be called AFTER tree itself is initialized, but BEFORE any nodes get added. This allows them to hook on node creation events,
            mostly useful for markup creation.
          </para>
    </section>
    
</section>

