Resizable

<!DOCTYPE html>
<html lang="ja">
  <head>
    <meta charset="utf-8">
    <title>jQuery UI</title>
    <link rel="stylesheet" href="jquery-ui.min.css">
    <script src="./external/jquery/jquery.js"></script>
    <script src="jquery-ui.min.js"></script>
    <style>
    .box {
    width: 100px;
    height: 100px;
    background: red;
    }
  </style>
  </head>
  <body>
  <div class="box">box</div>
  <script>
    $(function(){
      $('.box').draggable().resizable({
        handles: 'all',
        //aspectRatio: true
        stop: function (event, ui){
          console.log(ui.size.hight, ui.size.width);
        }
         });
      });
  </script>
  </body>
</html>

Selected

<script>
    $(function(){
       var selected = new Array();
       $('#selectable').selectable({
         selected: function(event, ui){
          selected.push(ui.selected.id);
          console.log(selected);
         },
         unselected: function(event, ui){
           var id = ui.unselected.id;
           selected.splice(selected.indexOf(id), 1);
           console.log(selected);
         }
       });
      });
  </script>