Location

安裝location

expo install expo-location

製作useLocation hook

import React,{useEffect} from 'react';
import {Text, StyleSheet, View, Button} from 'react-native';
import * as Location from 'expo-location';

const useLocation = () => {
  const [location, setLocation] = useState();
  
  const getLocation = async () => {
	const {granted} = await Location.requestPermisionsAsync();				//get permission to get the user's current location
	if(!granted) return;									//if not granted, return nothing
	const {coords:{latitude, longitude} } = await Location.getLastKnowPositionAsync();	//if granted, get the coordinates from the result
	setLocation({latitude, longitude});							//save the coordinates into the location variable
  }

useEffect( ()=>{
  getLocation();
},[]);
  
  return location;
}

export default useLocation;

使用useLocation hook

import React,{useEffect} from 'react';
import useLocation from '../hooks/useLocation';

function MyScreen = () => {
  const location = useLocation();
  return(
    <Button title="" onPress={()=>console.log(location)} />
  );
}