Flutter permission_handler 权限插件的使用详解

 <!-- Permission options for the `location` group -- 
 <key NSLocationWhenInUseUsageDescription</key 
 <string Need location when in use</string 
 <key NSLocationAlwaysAndWhenInUseUsageDescription</key 
 <string Always and when in use!</string 
 <key NSLocationUsageDescription</key 
 <string Older devices need location.</string 
 <key NSLocationAlwaysUsageDescription</key 
 <string Can I haz location always?</string 

 <!-- Permission options for the `mediaLibrary` group -- 
 <key NSAppleMusicUsageDescription</key 
 <string Music!</string 
 <key kTCCServiceMediaLibrary</key 
 <string media</string 

 <!-- Permission options for the `calendar` group -- 
 <key NSCalendarsUsageDescription</key 
 <string Calendars</string 

 <!-- Permission options for the `camera` group -- 
 <key NSCameraUsageDescription</key 
 <string camera</string 

 <!-- Permission options for the `contacts` group -- 
 <key NSContactsUsageDescription</key 
 <string contacts</string 

 <!-- Permission options for the `microphone` group -- 
 <key NSMicrophoneUsageDescription</key 
 <string microphone</string 

 <!-- Permission options for the `speech` group -- 
 <key NSSpeechRecognitionUsageDescription</key 
 <string speech</string 

 <!-- Permission options for the `sensors` group -- 
 <key NSMotionUsageDescription</key 
 <string motion</string 

 <!-- Permission options for the `photos` group -- 
 <key NSPhotoLibraryUsageDescription</key 
 <string photos</string 

 <!-- Permission options for the `reminder` group -- 
 <key NSRemindersUsageDescription</key 
 <string reminders</string 

 void chosePhoto(int index) async {
 PermissionHandler().requestPermissions(
 [PermissionGroup.photos, PermissionGroup.camera]).then((map) {
 if (map[PermissionGroup.photos] == PermissionStatus.granted ||
  map[PermissionGroup.camera] == PermissionStatus.granted) {
 chosePhotoFromPhone(context, index);
 }
 });
 }