antd-vue 时间选择器设置mode=year

<a-date-picker 
      format="YYYY"
	    mode="year"
	    :value="year"
	    :isopen="open"
	    @openChange="openChange"
	    @panelChange="panelChange" />

openChange(status) {
	if (status) {
	    this.isopen = true;
	} else {
	    this.isopen = false;
},
panelChange(value){
	this.year = value;
	this.isopen = false;
},