重定义extjs中button被点击后的样式

1.

var btn = new Ext.Button({text:'ddd'});
btn.on('',function(b){
    b.addClass('newCSS');
});

 

2.

/*编辑*/
.edit {
background-image: url(../images/toolbarIcon/edit.png) !important;
}

/*发布*/
.release {
background-image: url(../images/toolbarIcon/release.png) !important;
}

 

var btn= new Ext.ButtonGroup({
 
 id : 'edit',
       text : '编辑',
       handler : onRelease,
       iconCls : 'edit'//样式图片
 });

function onRelease(){
  btn.setIconClass('release');//更改图片
  btn.setText('发布');
}

 

{
											id:'_kbkg',
											xtype: 'button',
											text:'打开课表',
											iconCls:'unlock',
											listeners: {
										        'click': function(t){
													var text = t.getText();
													if(text == "打开课表"){
														t.setText("关闭课表");
														t.setIconClass('lock');
														KbCheck(1);
													}if(text == '关闭课表'){
														t.setText("打开课表");
														t.setIconClass('unlock');
														KbCheck(0);
													}
										        	
										        }
										    }
										}

  Ext.getCmp("xn_label").setText(" 学年: " + xn);
                    Ext.getCmp("xq_label").setText(" 学期: " + xq);
     
     //课表开关
     function KbCheck(v){
      Ext.Ajax.request({
         url: contextPath +'/system/lxdmglAction.do?method=getKbkg',
         /*
         success: function(request){
         },
         failure: function(request){
         },
         */
         params: { kva: v}
      });
        }
                    
     Ext.Ajax.request({
      url:contextPath +'/system/lxdmglAction.do?method=getKbkgValue',
      success:function(request){
       rs=Ext.decode(request.responseText);
       if (rs=="1") {
        Ext.getCmp("_kbkg").setText("关闭课表");
        Ext.getCmp("_kbkg").setIconClass('lock');
       }
      }/*,
      failure:function(request){
       Ext.Msg.alert("加载课表开关失败，请重试！");
      }*/
     });