问如何在反应性本机组件的初始负载上呈现承诺

EN

render(){
    let datePicker = <DatePickerIOS date={this.state.selectedValue} mode="date" timeZoneOffsetInMinutes={this.state.timeZoneOffsetInHours * 60} onDateChange={(date) => { this.setState({selectedValue: date})}} />;
    if (Platform.OS === "android"){
         datePicker = this.showAndroidDatePicker()
    } 

    return(
       <View>          
          {datePicker}
       </View>
    )
}

showAndroidDatePicker = async () => {
    try {
        const {action, year, month, day} = await DatePickerAndroid.open({
           date: this.state.selectedValue
        });
        if (action !== DatePickerAndroid.dismissedAction) {
           var date = new Date(year, month, day);
           this.setState({selectedValue: date.toLocaleDateString()});
        }
    }catch ({code, message}) {
        console.warn('Cannot open date picker', message);
    }
};