Code:
    Ext.widget("window", {      autoShow: true,
      width: 320,
      height: 240,
      layout: "fit",
      items: [{
        xtype: "treepanel",
        viewConfig: {
          plugins: [{ptype: "treeviewdragdrop"}]
        },
        rootVisible: false,
        store: Ext.create("Ext.data.TreeStore", {
          root: {
            children: [{
              "text": "1",
              leaf: true
            }, {
              "text": "2",
              leaf: true
            }],
            expanded: true
          }
        }),
        listeners: {
          itemmove: function () {
            console.log("I never get there");
          }
        }
      }]
    });
subject