Extjs中datefield监听事件

var date = {          fieldLabel: '年月',          name: 'uuu',  xtype:"datefield",  menuListeners : {          select: function(m, d){              this.setValue(d);              alert(d);          },          show : function(){ // retain focus styling              this.onFocus();          },          hide : function(){              this.focus.defer(10, this);              var ml = this.menuListeners;              this.menu.un("select", ml.select,  this);              this.menu.un("show", ml.show,  this);              this.menu.un("hide", ml.hide,  this);          }      }  }