22. Разрешения (Permissions)

iOS и Android требуют явного разрешения для камеры, геолокации, уведомлений и т.д.

Location

npx expo install expo-location

import * as Location from 'expo-location';

async function getCurrentLocation() {
  const { status } = await Location.requestForegroundPermissionsAsync();
  if (status !== 'granted') {
    Alert.alert('Нет доступа к геолокации');
    return;
  }

  const location = await Location.getCurrentPositionAsync({
    accuracy: Location.Accuracy.High,
  });
  console.log(location.coords.latitude, location.coords.longitude);
}

// Слежение за местоположением
const subscription = await Location.watchPositionAsync(
  { accuracy: Location.Accuracy.High, timeInterval: 5000, distanceInterval: 10 },
  (location) => console.log('Новая позиция:', location.coords)
);
subscription.remove();  // Очистка

Camera

import { CameraView, useCameraPermissions } from 'expo-camera';

function CameraScreen() {
  const [permission, requestPermission] = useCameraPermissions();

  if (!permission?.granted) {
    return <Button title="Разрешить камеру" onPress={requestPermission} />;
  }

  return <CameraView style={{ flex: 1 }} facing="back" />;
}

QR Scanner

<CameraView
  style={{ flex: 1 }}
  onBarcodeScanned={({ data, type }) => {
    console.log('Scanned:', data, type);
  }}
  barcodeScannerSettings={{ barcodeTypes: ['qr', 'code128'] }}
/>

Media Library & Image Picker

import * as ImagePicker from 'expo-image-picker';

const pickImage = async () => {
  const { status } = await ImagePicker.requestMediaLibraryPermissionsAsync();
  if (status !== 'granted') return;

  const result = await ImagePicker.launchImageLibraryAsync({
    mediaTypes: ImagePicker.MediaTypeOptions.Images,
    allowsEditing: true,
    aspect: [4, 3],
    quality: 0.8,
  });

  if (!result.canceled) setImage(result.assets[0].uri);
};

Разрешения в app.json

{
  "expo": {
    "ios": {
      "infoPlist": {
        "NSCameraUsageDescription": "Для сканирования QR-кодов",
        "NSLocationWhenInUseUsageDescription": "Для отображения карты",
        "NSPhotoLibraryUsageDescription": "Для загрузки аватара"
      }
    },
    "android": {
      "permissions": [
        "CAMERA",
        "ACCESS_FINE_LOCATION",
        "READ_EXTERNAL_STORAGE"
      ]
    }
  }
}

При отказе — предложить Настройки

import { Linking, Alert } from 'react-native';

const handleDenied = () => {
  Alert.alert(
    'Нет доступа',
    'Откройте Настройки и разрешите доступ к камере',
    [
      { text: 'Отмена', style: 'cancel' },
      { text: 'Настройки', onPress: () => Linking.openSettings() },
    ]
  );
};