Track That! How to Build a Location Tracker with Java

The world of Java is so promising, right? You have so many opportunities if you know how to code with it. Today we would like to explain to you how you can benefit from it and create an app like Number Tracker. If you don’t know what exactly it is, we will tell you right now. It’s one of the best location tracking apps that exist now. With it, you can enjoy whereabouts monitoring, location history, digital and driving safety, and even more. 

But creating a location tracking app in Java may seem rather difficult for beginners. Fear not! Imagine - it’s like a road trip with your trusty map (or GPS!). Today we are going to steer you through each step, so that you don’t get lost along the way. Ready to dive in? Let's get tracking!

Initial Elements

Before you hit the road, you need to pack the essentials:

1. Java Development Kit (JDK): Think of this as your backpack. Make sure you have the latest version installed. You can grab it from Oracle's website.

2. Android Studio and Xcode: Your all-in-one Swiss Army knives for Android and iOs development. 

3. A physical Android and iOS device or emulator: Your test ground. It’s like test-driving a car before you buy it.

Step-by-Step Guide

Today we are going to explain to you how to code an app for Android devices. In the following articles we will continue with iOS possibilities and solutions.

1. Set Up Your Project

Step 1: Open Android Studio and select “Create a new project”. Choose an empty activity template to start with a clean slate.

Step 2: Name your project something snazzy like “LocationTrackerPro” and select Java as the language. Set the Minimum API level to a reasonable version to support most devices (API level 21 is a good start).

Step 3: Click “Finish” and let Android Studio set up your project structure. It’s like setting up your campsite – everything in its place!

2. Add Permissions

Step 1: Open your AndroidManifest.xml file. This file is like the security gate to your app’s features.

Step 2: Add the following permissions inside the <manifest> tag. These permissions are essential for accessing the device’s location:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION"/>

3. Set Up Google Play Services

Step 1: Open your build.gradle file at the app level. This file manages your project’s dependencies – think of it as your toolkit.

Step 2: Add the following dependency for Google Play Services location:

implementation 'com.google.android.gms:play-services-location:19.0.1'

Step 3: Sync your project to download and integrate the dependency. This is like stocking up on supplies for your journey.

4. Request Location Permissions

Step 1: In your main activity, check if the location permissions have been granted. If not, request them from the user. Here’s how you do it:

• Use ContextCompat.checkSelfPermission to check if the permission is already granted.

• If not, use ActivityCompat.requestPermissions to prompt the user.

Step 2: Override the onRequestPermissionsResult method to handle the user's response. If permissions are granted, you’re good to go; if not, handle the denial gracefully.

5. Get the User’s Location

Step 1: Create an instance of FusedLocationProviderClient. This is your main tool for accessing the device’s location.

Step 2: Use the getLastLocation method to get the device's last known location. This is like checking the last known coordinates on a treasure map.

Step 3: Handle the location data, which includes latitude and longitude. Use this data to update your UI or save it for later use.

6. Update Location in Real-Time

Step 1: Create a LocationRequest object. This object specifies the quality of service for location updates (accuracy, interval, etc.).

Step 2: Set the desired interval for location updates using setInterval and setFastestInterval. This is akin to setting your GPS refresh rate.

Step 3: Set the priority to PRIORITY_HIGH_ACCURACY to get the best possible location data.

Step 4: Implement a LocationCallback to handle location updates. This callback will process the new location data as it arrives.

Step 5: Request location updates from the FusedLocationProviderClient using the requestLocationUpdates method. Ensure you handle updates on the main thread using a Looper.

7. Display the Location

Step 1: Add a MapView to your activity_main.xml layout file. This is your canvas for displaying the location.

Step 2: In your activity, initialize the MapView and set it up to handle lifecycle events like onCreate, onStart, etc.

Step 3: Use the getMapAsync method to asynchronously load the map. In the callback, add markers and move the camera to the user’s location.

Step 4: Customize the map as needed – you can add markers, draw paths, and more to make it visually appealing.

Tips for Beginners

1. Don’t try to build a full-fledged app right away. Focus on getting the basics right – fetching and displaying the location.

2. Google’s official location services documentation is your best friend. Refer to it whenever you’re stuck.

3. Play around with different settings in the LocationRequest to see how they affect accuracy and battery usage.

4. Test your app on multiple devices and in different environments (indoors, outdoors) to ensure reliability.

Building a location tracking app in Java can feel like coping with uncharted waters, but with our detailed guide, you’re well-equipped to reach your destination. If you follow these steps, you’ll have a solid foundation to create your app, and who knows? Maybe your app will be the next big thing in location tracking. Happy coding and may your code always compile on the first try!