React native expo iOS 无法在物理设备上请求后台位置

Question

我正在尝试使用 expo Location 获取后台权限。这适用于 android 和 iOS 模拟器，但不适用于物理 iOS 设备。

const askLoc = async () => {
    const requestForeground = await Location.requestForegroundPermissionsAsync();
    if (requestForeground.status === 'granted') {
      const requestBackground = await Location.requestBackgroundPermissionsAsync();
      if (requestBackground.status === 'granted') {
        console.log('background location granted');
      }
    }
  };

这就是我的app.json 的样子。

"ios": {
      "infoPlist": {
        "NSCameraUsageDescription": "This app uses the camera to send pictures or create a new profile photo.",
        "NSPhotoLibraryAddUsageDescription": "User can download documents that were previously uploaded by company",
        "NSPhotoLibraryUsageDescription": "User can upload Photos/Documents to be seen by his/her company",
        "NSLocationAlwaysUsageDescription": "Location is shared with users company while he/she is completing a task/job.",
        "NSLocationWhenInUseUsageDescription": "Location is shared with users company while he/she is completing a task/job.",
        "NSUserActivityTypes": ["INSendMessageIntent", "INStartCallIntent"],
        "UIBackgroundModes": ["location", "fetch"],
        "CFBundleAllowMixedLocalizations": true
      }
    },

Answer 1

调试问题需要考虑一些因素：

1. 确保启用位置访问。 await Location.hasServicesEnabledAsync()

2. 最近，您可能拒绝了位置许可 明确地。 requestForeground.status 将始终解析为 denied

检测requestForeground.canAskAgain是否设置为true，否则用户已经拒绝此权限，您可以打开设备设置并手动授予用户该权限。

这里权限响应类型定义

export interface PermissionResponse {
  status: PermissionStatus;
  expires: PermissionExpiration;
  granted: boolean;
  canAskAgain: boolean;
}