Question

我正在尝试获取IOS 14中的当前位置，但是当我签入EXPO时我没有任何回应设置，那里没有显示位置权限。我已经检查了模拟器和物理设备。

挂钩代码

import { useEffect, useState } from "react";
import * as Location from "expo-location";

export default useLocation = () => {
  const [location, setLocation] = useState();

  const getLocation = async () => {
    try {
      const { granted } = await Location.requestPermissionsAsync();
      if (!granted) return;
      const {
        coords: { latitude, longitude },
      } = await Location.getLastKnownPositionAsync();
      setLocation({ latitude, longitude });
    } catch (error) {
      console.log(error);
    }
  };

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

  return location;
};

响应

undefined

Answer 1

docs says Location.getLastKnownPositionAsync() 可能返回 null：

<块引用>

返回解析为 LocationObject 类型的对象的承诺或 null 如果它不可用或不符合给定的要求，例如最大年龄或要求的准确性。

所以你应该这样做：

import { useEffect, useState } from "react";
import * as Location from "expo-location";

export default useLocation = () => {
  const [location, setLocation] = useState();

  const getLocation = async () => {
    try {
      const { granted } = await Location.requestPermissionsAsync();
      if (!granted) return;
      const last = await Location.getLastKnownPositionAsync();
      if (last) setLocation(last);
      else {
        const current = await Location.getCurrentPositionAsync();
        setLocation(current);
      }
    } catch (error) {
      console.log(error);
    }
  };

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

  return location;
};

expo-location在ios中不起作用，并且在应用程序设置中未显示位置权限

1 个答案: