Expand Tree to a specific level

How can I use node.setExpanded(true); to expand the tree only to a certain level?

What I mean is that I've got 6 depth-levels and only want 5 to be expanded -- the last one should be excluded.

    $("#treeView").fancytree("getRootNode").visit(function(node){
        if(node.getLevel() < 3) {
            node.setExpanded(true);
        }
    });