*

Ejectable/ExpoTaskMgr.js

@@ -0,0 +1,34 @@
+import React from 'react';
+import { Text, TouchableOpacity } from 'react-native';
+import * as TaskManager from 'expo-task-manager';
+import * as Location from 'expo-location';
+
+const LOCATION_TASK_NAME = 'background-location-task';
+
+const requestPermissions = async () => {
+  const { status } = await Location.requestBackgroundPermissionsAsync();
+  if (status === 'granted') {
+    await Location.startLocationUpdatesAsync(LOCATION_TASK_NAME, {
+      accuracy: Location.Accuracy.Balanced,
+    });
+  }
+};
+
+const PermissionsButton = () => (
+  <TouchableOpacity onPress={requestPermissions}>
+    <Text>Enable background location</Text>
+  </TouchableOpacity>
+);
+
+TaskManager.defineTask(LOCATION_TASK_NAME, ({ data, error }) => {
+  if (error) {
+    // Error occurred - check `error.message` for more details.
+    return;
+  }
+  if (data) {
+    const { locations } = data;
+    // do something with the locations captured in the background
+  }
+});
+
+export default PermissionsButton;

Ejectable/GT2.tsx

@@ -170,7 +170,6 @@ export class GT2 {
     public reset() {
 
         this.distance   = 0.0;
-        this.co2Rate    = 0.0;  
         this.endPoint   = new Coordinate(0,0);
         this.startPoint = new Coordinate(0,0);
         this.v          = 0;

Ejectable/app.json

@@ -19,7 +19,13 @@
       "**/*"
     ],
     "ios": {
-      "supportsTablet": true
+      "supportsTablet": true,
+      "infoPlist": {
+        "UIBackgroundModes": [
+          "location",
+          "fetch"
+        ]
+      }
     },
     "android": {
       "adaptiveIcon": {

Ejectable/package-lock.json

@@ -6142,6 +6142,16 @@
       "resolved": "https://registry.npmjs.org/expo-status-bar/-/expo-status-bar-1.0.4.tgz",
       "integrity": "sha512-s7nc496D/Zn1NGiMJ5wu6HyIdXxbgGtmZZtbHm7rpbcmLdf28GmMSNHDx7M0t00BMhky7VAurTCUo+BJs8ugsw=="
     },
+    "expo-task-manager": {
+      "version": "9.2.2",
+      "resolved": "https://registry.npmjs.org/expo-task-manager/-/expo-task-manager-9.2.2.tgz",
+      "integrity": "sha512-GDObZYoCT1bwYXYtT9RinRhR7Y+mCy6DvO7OvRFW3hgxHVXvAM8YFA8jr3airY0XF73aT35/nFnOe+MFCELXFA==",
+      "requires": {
+        "@expo/config-plugins": "^3.0.0",
+        "expo-modules-core": "~0.2.0",
+        "unimodules-app-loader": "~2.2.0"
+      }
+    },
     "expo-web-browser": {
       "version": "9.2.0",
       "resolved": "https://registry.npmjs.org/expo-web-browser/-/expo-web-browser-9.2.0.tgz",
@@ -15002,6 +15012,11 @@
       "resolved": "https://registry.npmjs.org/unicode-property-aliases-ecmascript/-/unicode-property-aliases-ecmascript-1.1.0.tgz",
       "integrity": "sha512-PqSoPh/pWetQ2phoj5RLiaqIk4kCNwoV3CI+LfGmWLKI3rE3kl1h59XpX2BjgDrmbxD9ARtQobPGU1SguCYuQg=="
     },
+    "unimodules-app-loader": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/unimodules-app-loader/-/unimodules-app-loader-2.2.0.tgz",
+      "integrity": "sha512-porQWVWu7meIrCJ+c+H7eJyeC2rHioLUZiv4UcOs33SAyUhR4X05tCC8NIOuQJsF08Fj3a0ck7HUsd5xq+LqKA=="
+    },
     "union-value": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/union-value/-/union-value-1.0.1.tgz",

Ejectable/package.json

@@ -33,7 +33,8 @@
     "react-native-reanimated": "~2.2.0",
     "react-native-safe-area-context": "3.2.0",
     "react-native-screens": "~3.4.0",
-    "react-native-web": "~0.13.12"
+    "react-native-web": "~0.13.12",
+    "expo-task-manager": "~9.2.2"
   },
   "devDependencies": {
     "@babel/core": "^7.9.0",

Ejectable/screens/SettingsScreen.tsx

@@ -36,7 +36,7 @@ export default function SettingsScreen() {
        <Button
        title="Gasoline"
        onPress={() => {
-           Trips.co2Rate   = 285.0; 
+           Trips.co2Rate   = 255.0; 
            Trips.CO2Effect = "carbon burden";
            Alert.alert('Gasoline Selected \n 255 g for driver \n only passenger / km')}
          }
@@ -44,7 +44,7 @@ export default function SettingsScreen() {
        <Button
        title="Food"
        onPress={() => {
-            Trips.co2Rate = -285.0; 
+            Trips.co2Rate = -255.0; 
             Trips.CO2Effect = "carbon relief";
             Alert.alert('Savings vs Gasoline Selected')}
           }

Ejectable/screens/TripScreen.tsx

@@ -1,6 +1,6 @@
 import * as React from 'react';
 import { useState } from 'react';
-import { Alert, Button, StyleSheet } from 'react-native';
+import { Alert, BackHandler, Button, StyleSheet } from 'react-native';
 import { Text, View } from '../components/Themed';
 import { ScreenInfo2 } from '../components/ScreenInfo';
 import  EndScreenInfo  from '../components/EndScreenInfo';
@@ -55,7 +55,7 @@ function pauseTrip() {
 
 function endTrip() {  Trips.end(); }
 
-export default function TripScreen( navigation:any ) {
+export default function TripScreen( ) {
 
   const [sButtonText, setSButtonText] = useState("Start"); 
   const [pButtonText, setPButtonText] = useState("Pause");
@@ -92,7 +92,7 @@ export default function TripScreen( navigation:any ) {
        <View style={styles.separator} lightColor="#eee" darkColor="rgba(255,255,255,0.1)" />  
        <EndScreenInfo path="/screens/TripScreen.tsx" />
        <Button title={'Dismiss'}
-        onPress={() => { toggleEndPending(); if (getEndPending()) Alert.alert("t"); else Alert.alert("f"); }}
+        onPress={() => { toggleEndPending();  }}
       />
      </View>
     );