backhandler fixed

App.js

@@ -17,7 +17,7 @@ class App extends React.PureComponent {
   componentDidMount() {
     Orientation.lockToPortrait();
   }
-  componentDidUpdate(){
+  componentDidUpdate() {
     Orientation.lockToPortrait();
   }
 

screens/home.js

@@ -10,9 +10,11 @@ import {
   StyleSheet,
   ScrollView,
   Image,
+  BackHandler,
 } from 'react-native';
 import {Icon} from 'react-native-elements';
 import Orientation from 'react-native-orientation';
+const exitApp = () => BackHandler.exitApp();
 
 class Home extends React.PureComponent {
 
@@ -26,7 +28,9 @@ class Home extends React.PureComponent {
     // Orientation.lockAsync(Orientation.OrientationLock.PORTRAIT_UP);
   }
 
+
   render() {
+    BackHandler.addEventListener('hardwareBackPress', exitApp);
     return (
       <View style={styles.container}>
         <ImageBackground

screens/logbook.js

@@ -10,6 +10,7 @@ import {
   StyleSheet,
   ScrollView,
  // Alert,
+ BackHandler,
 } from 'react-native';
 import AsyncStorage from '@react-native-async-storage/async-storage';
 import Orientation from 'react-native-orientation';
@@ -43,8 +44,13 @@ class LogBook extends React.PureComponent {
     this.displayData();
   }
 
+   homeExit = async () => {
+    this.props.navigation.navigate('1');
+    //Orientation.lockToPortrait();
+  };
 
   render() {
+     BackHandler.addEventListener('hardwareBackPress', this.homeExit);
     return (
       <View style={styles.container}>
         <ImageBackground

screens/quiz.js

@@ -599,9 +599,9 @@ class Quiz extends React.Component {
     }
   };
 
-  homeExit = () => {
+  homeExit = async () => {
     // this.props.navigation.navigate('1');
-      Alert.alert('Hold on!', 'Are you sure you want to stop?', [
+      Alert.alert('Hold on!', 'Are you sure you want to exit?', [
       {
         text: 'Cancel',
         onPress: () => null,
@@ -617,16 +617,16 @@ class Quiz extends React.Component {
      Orientation.lockToPortrait();
   };
 
-  async componentDidMount() {
+  componentDidMount() {
   //this.removeArray();
-   BackHandler.addEventListener('hardwareBackPress', this.homeExit);
+  // BackHandler.addEventListener('hardwareBackPress', this.homeExit);
     Orientation.lockToLandscape();
     this.displayData();
   }
 
     componentWillUnmount() {
        this.removeArray();
-        BackHandler.addEventListener('hardwareBackPress', this.homeExit);
+     //   BackHandler.addEventListener('hardwareBackPress', this.homeExit);
     //clearInterval(this.interval);
    // Orientation.lockToLandscape();
   }
@@ -752,6 +752,7 @@ this.setState({records: []});
   };
 
   render() {
+    BackHandler.addEventListener('hardwareBackPress', this.homeExit);
       const {
       selectedKeywordStyle,
       buttonStyle,

screens/settings.js

@@ -12,6 +12,7 @@ import {
   ScrollView,
   Dimensions,
  // TextInput,
+ BackHandler,
 } from 'react-native';
 import Orientation from 'react-native-orientation';
 import Notes from './data';
@@ -172,7 +173,14 @@ export default class Settings extends React.Component {
   }
   }
 
+    homeExit = async () => {
+    this.props.navigation.navigate('1');
+
+    //Orientation.lockToPortrait();
+  };
+
   render() {
+        BackHandler.addEventListener('hardwareBackPress', this.homeExit);
     return (
       <View style={styles.container}>
           <SafeAreaView>