Programming Tutorials

Start background location tracking after login in expo react native

By: Adeline in React-Native Tutorials on 2023-05-16  

If you want to have a background job in an expo app to get the location of the device continuously and the job should start only after login is successful. You can define the background task in app.js and then when login is successful in another component, (for example user.js) you can start the job.

To achieve this in an Expo app, you can follow these steps:

  1. Install the required packages:

    npm install expo-location expo-task-manager
    
  2. Set up the background task in your app.js file:

    import * as Location from 'expo-location';
    import * as TaskManager from 'expo-task-manager';
    
    // Define the task name
    const BACKGROUND_TASK_NAME = 'LOCATION_TASK';
    
    // Define the background task handler
    TaskManager.defineTask(BACKGROUND_TASK_NAME, async ({ data, error }) => {
      if (error) {
        console.error('Error in background task:', error);
        return;
      }
      if (data) {
        const { locations } = data;
        // Process the received locations here
        console.log('Received locations:', locations);
      }
    });
    
    // Request permission for location updates
    const requestLocationPermission = async () => {
      const { status } = await Location.requestForegroundPermissionsAsync();
      if (status === 'granted') {
        Location.startLocationUpdatesAsync(BACKGROUND_TASK_NAME, {
          accuracy: Location.Accuracy.Balanced,
        });
      }
    };
    
    // Call the permission function
    requestLocationPermission();
    
  3. In your user.js component, start the background task after successful login:

    import * as TaskManager from 'expo-task-manager';
    
    // Define the same task name as in app.js
    const BACKGROUND_TASK_NAME = 'LOCATION_TASK';
    
    // Start the background task after successful login
    const startBackgroundTask = () => {
      TaskManager.isTaskRegisteredAsync(BACKGROUND_TASK_NAME).then((isRegistered) => {
        if (isRegistered) {
          TaskManager.getRegisteredTasksAsync().then((tasks) => {
            const backgroundTask = tasks.find((task) => task.taskName === BACKGROUND_TASK_NAME);
            if (backgroundTask) {
              TaskManager.startTaskAsync(BACKGROUND_TASK_NAME).then(() => {
                console.log('Background task started');
              });
            }
          });
        }
      });
    };
    
    // Call the function after successful login
    startBackgroundTask();
    

With this setup, the background task defined in app.js will continuously receive the device's location updates. The task will start running only after the user successfully logs in, triggered by the startBackgroundTask function in the user.js component. Make sure to handle any necessary cleanup or stopping of the task as per your requirements.






Add Comment

* Required information
1000

Comments

No comments yet. Be the first!

Most Viewed Articles (in React-Native )

npm install vs npx expo install

expo-secure-store to store sensitive data securely in React Native

expo-secure-store vs expo-file-system in expo - react native

use axios in Expo to call APIs

Start background location tracking after login in expo react native

react-native-background-job alternative in expo app

Some dependencies are incompatible with the installed expo version:

Send push notifications to android/ios sample code using expo - react native

react-native-android-location-services-dialog-box alternative in expo

disable the back arrow in the header of a screen in a React Navigation Stack Navigator

Remove all installed dependencies and install them again

set up a global error handler in React Native (expo)

state vs props in React Native

Error Handling in TextInput - React Native

loadAsync() vs useFonts() in expo - react native

Latest Articles (in React-Native)

Session variables in React Native - Expo

use axios in Expo to call APIs

Start background location tracking after login in expo react native

set up a global error handler in React Native (expo)

SafeAreaView in React Native

Some dependencies are incompatible with the installed expo version:

disable the back arrow in the header of a screen in a React Navigation Stack Navigator

react-native-android-location-services-dialog-box alternative in expo

Error Handling in TextInput - React Native

react-native-background-job alternative in expo app

'import' and 'export' may only appear at the top level - React Native

OpenType (OTF) vs TrueType (TTF)

loadAsync() vs useFonts() in expo - react native

expo-secure-store vs expo-file-system in expo - react native

Send push notifications to android/ios sample code using expo - react native