navigator.geolocation.getCurrentPosition无法正常工作

我似乎navigator.geolocation无法上班。它进入错误代码为3的错误功能，错误消息为“位置请求超时”，下面的代码在做什么？

import { AppRegistry } from 'react-native'
import { App } from './src'

var options = {
    enableHighAccuracy: true,
    timeout: 5000,
    maximumAge: 0
  };

  function success(pos) {
    var crd = pos.coords;

    console.log('Your current position is:');
    console.log(`Latitude : ${crd.latitude}`);
    console.log(`Longitude: ${crd.longitude}`);
    console.log(`More or less ${crd.accuracy} meters.`);
  }

  function error(err) {
    console.warn(`ERROR(${err.code}): ${err.message}`);
  }

  navigator.geolocation.getCurrentPosition(success, error, options);

GLOBAL.XMLHttpRequest = GLOBAL.originalXMLHttpRequest || GLOBAL.XMLHttpRequest
console.error = (error) => error.apply
AppRegistry.registerComponent('vepo', () => App)