Method addSubItem

examples/common/Components.cpp:21–21

    virtual String getUniqueName() const = 0;

    void addSubItem (PluginTreeBase* itm)   { subitems.add (itm);       }
    int getNumSubItems()                    { return subitems.size();   }
    PluginTreeBase* getSubItem (int idx)    { return subitems[idx];     }