Şehir seçimi

import { useState } from 'react';
import { View, Text, StyleSheet } from 'react-native';
import { Picker } from '@react-native-picker/picker';

const WEATHER_BY_CITY = {
  'İstanbul': { city: 'İstanbul', temp: 18, condition: 'Bulutlu' },
  'Ankara': { city: 'Ankara', temp: 22, condition: 'Güneşli' }
};
const getWeather = (city) => WEATHER_BY_CITY[city] || WEATHER_BY_CITY['İstanbul'];

function App() {
  const [weather, setWeather] = useState(getWeather('İstanbul'));
  return (
    <View style={styles.container}>
      <Text style={styles.city}>{weather.city}</Text>
      <Text style={styles.temp}>{weather.temp}°C</Text>
      <Text style={styles.condition}>{weather.condition}</Text>
      <Picker
        selectedValue={weather.city}
        onValueChange={(value) => setWeather(getWeather(value))}>
        <Picker.Item label='İstanbul' value='İstanbul' />
        <Picker.Item label='Ankara' value='Ankara' />
      </Picker>
    </View>
  );
}
const styles = StyleSheet.create({
  container: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  city: { fontSize: 24, marginBottom: 8 },
  temp: { fontSize: 64, fontWeight: 'bold' },
  condition: { fontSize: 18, color: '#555' }
});
export default App;