jt

<!doctype html>
<html>
<head>
    <title>jstree test</title>

    <style>
        html { margin:0; padding:0; font-size:62.5%; }
        body { max-width:800px; min-width:300px; margin:0 auto; padding:20px 10px; font-size:14px; font-size:1.4em; }
        h1 { font-size:1.8em; }
        .demo { overflow:auto; border:1px solid silver; min-height:100px; }
    </style>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jstree/3.1.1/themes/default/style.min.css" />

</head>
<body>
    <div id="testtree">
        <ul>
            <li id="1" title="ID:1"><a>Fruits and Vegetables</a>
                <ul>

                    <li id="11" title="ID:11"><a>Fruit</a>
                        <ul>
                            <li id="111" title="ID:111"><a>Apple</a></li>
                            <li id="112" title="ID:112"><a>Banana</a></li>
                        </ul>
                    </li>

                    <li id="12" title="ID:12"><a>Vegetables</a>
                        <ul>
                            <li id="121" title="ID:121"><a>Zucchini</a></li>
                            <li id="122" title="ID:122"><a>Tomato</a>
                                <ul>
                                    <li id="1221" title="ID:1221"><a>Red Tomato</a></li>
                                    <li id="1222" title="ID:1222"><a>Green Tomato</a></li>
                                </ul>
                            </li>
                        </ul>
                    </li>

                </ul>
            </li>
        </ul>
    </div>

    <button>Summary</button>

    <script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jstree/3.1.1/jstree.min.js"></script>

    <script>

        $(document).ready(function() {

            $('#testtree').jstree({
                'plugins' : [ "checkbox", "contextmenu", "dnd", "massload", "search", "sort", "state", "types", "unique", "wholerow" ]
            });

        })

        var button = document.querySelector( "button" );

        button.addEventListener( "click", function( ev ) {
            var id = $("#testtree").jstree("get_selected")
            alert( "Your Selection: "+id);
        }, false);

    </script>
</body>
</html>