<input data-idx="1" type="text" name="username" confirm-type="next" bindinput="usernameValue" bindconfirm="confirmListener" focus="{{focus && focusIndex == 1}}"/>
<input data-idx="2" type="text" name="password" bindinput="passwdValue" bindconfirm="confirmListener" focus="{{focus && focusIndex == 2}}" password/>
js:
  data:{
    focusIndex:1
  },
  confirmListener:function(e){
    setTimeout(() => {
      let currentIndex=e.currentTarget.dataset.idx
      if(currentIndex < 2){
        this.setData({
          focusIndex:currentIndex + 1
        })
      }else{
        this.setData({focus:false})
      }
      console.log(this.data.focusIndex)      
    }, 300);
  },

动态修改focusIndex参数，currentIndex+1这个不对应该如何写？