Switch button in react-native - react-native

Question

Hi I have a problem with the switch button in react-native. I'm using it to toggle or not the activation of push notification. The problem is that if I quit the application, the state of the switch is getting back to false, it's not saving the state ? What am I doing wrong ?
Here is my code :
constructor(props) {
super(props)
this.state = {
switchValue:false
}
}
toggleSwitch = (value) => {
this.setState({switchValue: value})
if(this.state.switchValue){
console.log("Unsubscribed")
} else {
console.log("Subscribed")
}
}
render() {
return (
<SafeAreaView>
<ScrollView>
<View style = {styles.view_container}>
<Text style = {styles.titre}>Notifications</Text>
<Text style = {{marginTop:9}}>Permet de recevoir des alertes lorsque de nouvelles vidéos sont disponibles.</Text>
<View style = {{marginTop: 30, justifyContent:"center", alignContent:"center"}}>
<View style = {styles.row}>
<View style = {styles.row_infos}>
<Image source={require('../Images/couleurs/icons8-belier-100.png')} style = {styles.image}/>
<Text style = {{fontWeight:"bold", fontSize:16,lineHeight:16, color:"#7c4dff"}}>Bélier</Text>
</View>
<Switch
onValueChange = {this.toggleSwitchBelier}
value = {this.state.switchValueBelier}
trackColor={{false:'#000000', true:'#7c4dff'}}
/>
</View>
</View>
</View>
</ScrollView>
</SafeAreaView>
)}

Answer 1

When you quit your Application, all saved variables in the state will be "resetted".
If you would like to keep the state of the toggle button, i would recommend you to use the AsyncStorage, provided by expo.
See here:
https://docs.expo.io/versions/v36.0.0/react-native/asyncstorage/
Just set the item when the toggle-function is triggered like this:
import { AsyncStorage } from 'react-native';
AsyncStorage.setItem('buttonToggle', 'true');
And when you start the application again, load the current status from the AsyncStorage:
const value = await AsyncStorage.getItem('buttonToggle');
if (!!value && value === 'true'){
// Do whatever you like
}