return model.getTreeView();
TreeView treeView = model.getTreeView(); if (treeView == null) { model.createTreeView(); treeView = model.getTreeView(); treeView.addPropertyChangeListener(controller); } return treeView;
    public TreeView getTreeView()    {        int state = model.getState();        if (state != LOADING_THUMBNAILS && state != READY)            throw new IllegalStateException(                   "This method can only be invoked in the LOADING_THUMBNAILS "+                        "or READY state.");        return model.getTreeView();    }