Reactnative TypeError：undefined is not an object(判断'navigator.geolocation.requestAuthorization')

我正试图打电话:

`navigator.geolocation.requestAuthorization();`

请求地理定位许可.

但是，这会导致在iOS模拟器中运行时出错

这在某一点上起作用，但停止了.我试图删除并创建一个新项目.我还try 卸载/重新安装node并对本机cli做出react .

import React, {Fragment, Component} from 'react';
import {
  SafeAreaView,
  StyleSheet,
  ScrollView,
  View,
  Text,
  StatusBar,
} from 'react-native';

import {
  Header,
  LearnMoreLinks,
  Colors,
  DebugInstructions,
  ReloadInstructions,
} from 'react-native/Libraries/NewAppScreen';

export default class App extends Component {

    constructor(props)
    {
        super(props);

        navigator.geolocation.requestAuthorization();
    }

    render() {

        return (

                <View style={styles.MainContainer}>
                <SafeAreaView style={{flex: 1, backgroundColor: '#fff'}}>
                <Text style={styles.sectionTitle}>Hello World!</Text>
                </SafeAreaView>
                </View>

                );
    }
}

const styles = StyleSheet.create({
  MainContainer :{
     justifyContent: 'center',
     flex:1,
     margin: 5,
     marginTop: (Platform.OS === 'ios') ? 20 : 0,
  },
  sectionTitle: {
    fontSize: 24,
    fontWeight: '600',
    color: Colors.black,
  },
});

我得到了这个错误:

[error][tid:com.facebook.react.JavaScript] TypeError: undefined is not an object (evaluating 'navigator.geolocation.requestAuthorization')

This error is located at:
    in App (at renderApplication.js:40)
    in RCTView (at View.js:35)
    in View (at AppContainer.js:98)
    in RCTView (at View.js:35)
    in View (at AppContainer.js:115)
    in AppContainer (at renderApplication.js:39)