react navigation传值给上一页面

使用新的导航组件react navigation，传值方式略微发生了一些改变

A页面到B页面

pushaddremark(){
    let _this=this;
    this.props.navigation.navigate("addRemarks",
    {
      info:this.state.strdate+this.state.day+"日",

      getparams(textvalue){
        _this.fetchStories(textvalue);
      }

    });
}

B页面代码

constructor(props) {
    super(props);
    this.state =  {
       params:this.props.navigation.state.params,
       todaytime:"this.props.todaytime",
       textvalue:""
    };
}
presssave(){ 
      this.state.params.getparams(this.state.textvalue);
      this.props.navigation.goBack();
}