App.js

import { StatusBar } from 'expo-status-bar';
import React,{useState, useEffect} from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';
import { NavigationContainer } from '@react-navigation/native';
import { createStackNavigator } from '@react-navigation/stack';
import { BarCodeScanner } from 'expo-barcode-scanner';

function HomeScreen({navigation}) {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text>Scanneur de code</Text>
      <Button
        title="Scanner un code"
        onPress={() => navigation.navigate('Scanner')}
      />
    </View>
  );
}

function ScannerScreen({navigation}) {
  const [hasPermission, setHasPermission] = useState(null);
  const [scanned, setScanned] = useState(false);

  useEffect(() => {
    (async () => {
      const { status } = await BarCodeScanner.requestPermissionsAsync();
      setHasPermission(status === 'granted');
    })();
  }, []);

  const handleBarCodeScanned = ({ type, data }) => {
    setScanned(true);
    navigation.navigate("Result",{
      type: type,
      data: data
    });
    setScanned(false);
  };

  if (hasPermission === null) {
    return <Text>Requesting for camera permission</Text>;
  }
  if (hasPermission === false) {
    return <Text>No access to camera</Text>;
  }

  return (
    <View style={styles.container}>
      <BarCodeScanner
        onBarCodeScanned={scanned ? undefined : handleBarCodeScanned}
        style={StyleSheet.absoluteFillObject}
      />
    </View>
  );
}

function ResultScreen({ route, navigation }) {
  const { type, data } = route.params;
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text>Résultat du scan</Text>
      <Text>type : {type}</Text>
      <Text>data : {data}</Text>
      <Button
        title="Scanner un autre code"
        onPress={() => navigation.navigate('Scanner')}
      />
    </View>
  );
}

const Stack = createStackNavigator();

function App() {
  return (
    <NavigationContainer>
      <Stack.Navigator>
        <Stack.Screen name="Home" component={HomeScreen} />
        <Stack.Screen name="Result" component={ResultScreen} />
        <Stack.Screen name="Scanner" component={ScannerScreen} />
      </Stack.Navigator>
    </NavigationContainer>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    flexDirection: 'column',
    justifyContent: 'center',
  },
}); 

export default App;