sort冒泡

var arr = this.npcLayer.getChildren()
arr.sort(function(a,b){
    return a.y < b.y           
})
var ob=[{age:99},{age:9},{age:399},{age:199}]
ob.sort(function(a,b){
    return a.age > b.age?1:-1
})
cc.log('???', ob.toString())