How can I enable the handle on layout manager?

Given the following javascript code :

var layoutFull = new YAHOO.widget.Layout({
                    units: [
                        {
                            position: 'left',
                            header: 'Right',
                            width: 300,
                            resize: true,
                            collapse: true,
                            s开发者_Python百科croll: true,
                            body: 'right1',
                            animate: true
                        },
                        {
                            position: 'center',
                            body: 'Da center...'
                        }
                    ]
                });
                layoutFull.render();

I can have a full layout with a collapsible left pane. But there is a fine line between left and center parts. I would like to be able to drag this line for resizing both left and center part as in this example : http://developer.yahoo.com/yui/examples/layout/page_layout_source.html.

Which property should I enable in the layout configuration ? Looking at sample or the API doc didn't give me any luck.

I'm wondering if the following two libraries need to be included ...

<script type="text/javascript" src="../../build/dragdrop/dragdrop-min.js"></script>
<script type="text/javascript" src="../../build/resize/resize-min.js"></script>

Without 'seeing' the html, its rather hard to guess. Some 'magic' might occur by adding these two. Just a hunch. :)