react-native-vision-camera/package/example/src/CodeScannerPage.tsx
2023-11-10 13:25:28 +01:00

121 lines
3.7 KiB
TypeScript

import * as React from 'react'
import { useCallback, useRef, useState } from 'react'
import { Alert, AlertButton, Linking, StyleSheet, View } from 'react-native'
import { Code, useCameraDevice, useCodeScanner } from 'react-native-vision-camera'
import { Camera } from 'react-native-vision-camera'
import { CONTENT_SPACING, CONTROL_BUTTON_SIZE, SAFE_AREA_PADDING } from './Constants'
import { useIsForeground } from './hooks/useIsForeground'
import { StatusBarBlurBackground } from './views/StatusBarBlurBackground'
import { PressableOpacity } from 'react-native-pressable-opacity'
import IonIcon from 'react-native-vector-icons/Ionicons'
import type { Routes } from './Routes'
import type { NativeStackScreenProps } from '@react-navigation/native-stack'
import { useIsFocused } from '@react-navigation/core'
const showCodeAlert = (value: string, onDismissed: () => void): void => {
const buttons: AlertButton[] = [
{
text: 'Close',
style: 'cancel',
onPress: onDismissed,
},
]
if (value.startsWith('http')) {
buttons.push({
text: 'Open URL',
onPress: () => {
Linking.openURL(value)
onDismissed()
},
})
}
Alert.alert('Scanned Code', value, buttons)
}
type Props = NativeStackScreenProps<Routes, 'CodeScannerPage'>
export function CodeScannerPage({ navigation }: Props): React.ReactElement {
// 1. Use a simple default back camera
const device = useCameraDevice('back')
// 2. Only activate Camera when the app is focused and this screen is currently opened
const isFocused = useIsFocused()
const isForeground = useIsForeground()
const isActive = isFocused && isForeground
// 3. (Optional) enable a torch setting
const [torch, setTorch] = useState(false)
// 4. On code scanned, we show an aler to the user
const isShowingAlert = useRef(false)
const onCodeScanned = useCallback((codes: Code[]) => {
console.log(`Scanned ${codes.length} codes:`, codes)
const value = codes[0]?.value
if (value == null) return
if (isShowingAlert.current) return
showCodeAlert(value, () => {
isShowingAlert.current = false
})
isShowingAlert.current = true
}, [])
// 5. Initialize the Code Scanner to scan QR codes and Barcodes
const codeScanner = useCodeScanner({
codeTypes: ['qr', 'ean-13'],
onCodeScanned: onCodeScanned,
})
return (
<View style={styles.container}>
{device != null && (
<Camera
style={StyleSheet.absoluteFill}
device={device}
isActive={isActive}
codeScanner={codeScanner}
torch={torch ? 'on' : 'off'}
enableZoomGesture={true}
/>
)}
<StatusBarBlurBackground />
<View style={styles.rightButtonRow}>
<PressableOpacity style={styles.button} onPress={() => setTorch(!torch)} disabledOpacity={0.4}>
<IonIcon name={torch ? 'flash' : 'flash-off'} color="white" size={24} />
</PressableOpacity>
</View>
{/* Back Button */}
<PressableOpacity style={styles.backButton} onPress={navigation.goBack}>
<IonIcon name="chevron-back" color="white" size={35} />
</PressableOpacity>
</View>
)
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: 'black',
},
button: {
marginBottom: CONTENT_SPACING,
width: CONTROL_BUTTON_SIZE,
height: CONTROL_BUTTON_SIZE,
borderRadius: CONTROL_BUTTON_SIZE / 2,
backgroundColor: 'rgba(140, 140, 140, 0.3)',
justifyContent: 'center',
alignItems: 'center',
},
rightButtonRow: {
position: 'absolute',
right: SAFE_AREA_PADDING.paddingRight,
top: SAFE_AREA_PADDING.paddingTop,
},
backButton: {
position: 'absolute',
left: SAFE_AREA_PADDING.paddingLeft,
top: SAFE_AREA_PADDING.paddingTop,
},
})