extjs动态改变样式

{
width:438,
height:440,
name:'loginDiv',
ui:'123',
x: '50%' ,
y: 200,
border:true,
bodyStyle:{
'border':'#d3d3d3 1px solid',
'background-color':'#fff',
'border-radius':'2px'
}
}

listeners:{
resize : function() {
//自动登陆框宽高
var loginDiv = this.down('[name=loginDiv]');
var footDiv = this.down('[name=footDiv]');
var windowX = Ext.getBody().getWidth();
var windowY = Ext.getBody().getHeight();
loginDiv.setX(windowX*0.5 - 219);
loginDiv.setY(windowY*0.5 - 220);
footDiv.setBodyStyle({
'padding-left':(windowX*0.5 - 225) + "px"
})
}
}