activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/ShowLocationButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show Location"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.aero.gpstracker">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.GpsTracker">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

GPSTracker.java

package Utilities;


import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.Settings;
import android.util.Log;

import androidx.core.app.ActivityCompat;

/**
 * Ahmet Ertugrul OZCAN
 * Cihazin konum bilgisini goruntuler
 */
public class GPSTracker extends Service implements LocationListener
{
	private final Context mContext;
	
	// Cihazda gps acik mi?
	boolean isGPSEnabled = false;
	
	// Cihazda veri baglantisi aktif mi?
	boolean isNetworkEnabled = false;
	
	// Konum guncellemesi gerektirecek minimum degisim miktari
	private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // metre
	
	// Konum guncellemesi gerektirecek minimum sure miktari
	private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // dakika
	
	// LocationManager nesnesi
	protected LocationManager locationManager;
	
	//
	// Kurucu Metod - Constructor
	//
	public GPSTracker(Context context)
	{
		this.mContext = context;
		getLocation();
	}
	
	//
	// Konum bilgisini dondurur
	//
	public Location getLocation()
	{
		Location location = null;
		
		try
		{
			locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
			
			// GPS acik mi?
			isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
			
			// Internet acik mi?
			isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
			
			if (!isGPSEnabled && !isNetworkEnabled)
			{
				throw new Exception("Check GPS or internet connection!");
			}
			else
			{
				// Once internetten alinan konum bilgisi kayitlanir
				if (isNetworkEnabled)
				{
					if (ActivityCompat.checkSelfPermission((Activity)mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission((Activity)mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
					{
						throw new Exception("Permission needed for location!");
					}
					
					locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
					Log.d("Network", "Network");
					if (locationManager != null)
					{
						location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
					}
				}
				// GPS'ten alinan konum bilgisi;
				if (isGPSEnabled)
				{
					if (location == null)
					{
						locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
						Log.d("GPS Enabled", "GPS Enabled");
						if (locationManager != null)
						{
							location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
						}
					}
				}
			}
		}
		catch (Exception e)
		{
			e.printStackTrace();
		}
		
		return location;
	}
	
	@Override
	public void onLocationChanged(Location location)
	{
	}
	
	@Override
	public void onProviderDisabled(String provider)
	{
	}
	
	@Override
	public void onProviderEnabled(String provider)
	{
	}
	
	@Override
	public void onStatusChanged(String provider, int status, Bundle extras)
	{
	}
	
	@Override
	public IBinder onBind(Intent arg0)
	{
		return null;
	}
	
	// Konum bilgisi kapali ise kullaniciya ayarlar sayfasina baglanti iceren bir mesaj goruntulenir
	public void showSettingsAlert()
	{
		AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
		
		// Mesaj basligi
		alertDialog.setTitle("GPS Kapalı");
		
		// Mesaj
		alertDialog.setMessage("Konum bilgisi alınamıyor. Ayarlara giderek gps'i aktif hale getiriniz.");
		
		// Mesaj ikonu
		//alertDialog.setIcon(R.drawable.delete);
		
		// Ayarlar butonuna tiklandiginda
		alertDialog.setPositiveButton("Ayarlar", new DialogInterface.OnClickListener()
		{
			public void onClick(DialogInterface dialog,int which)
			{
				Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
				mContext.startActivity(intent);
			}
		});
		
		// Iptal butonuna tiklandiginda
		alertDialog.setNegativeButton("İptal", new DialogInterface.OnClickListener()
		{
			public void onClick(DialogInterface dialog, int which)
			{
				dialog.cancel();
			}
		});
		
		// Mesaj kutusunu goster
		alertDialog.show();
	}
	
	// LocationManager'in gps isteklerini durdurur
	public void stopUsingGPS()
	{
		if (locationManager != null)
		{
			locationManager.removeUpdates(GPSTracker.this);
		}
	}
}

MainActivity.java

package com.aero.gpstracker;

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.location.Location;
import android.os.Bundle;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.Toast;

import android.os.Bundle;

import Utilities.GPSTracker;

public class MainActivity extends AppCompatActivity
{
	private Button ShowLocationButton;
	
	// GPSTracker nesnesi
	private GPSTracker gpsTracker;
	
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		ShowLocationButton = (Button) findViewById(R.id.ShowLocationButton);
		
		// ShowLocationButton butonuna tiklandiginda
		ShowLocationButton.setOnClickListener(new View.OnClickListener()
		{
			@Override
			public void onClick(View arg0)
			{
				gpsTracker = new GPSTracker(MainActivity.this);
				Location location = gpsTracker.getLocation();
				
				// Eger konum bilgisi alinabiliyorsa ekranda goruntulenir
				if (location != null)
				{
					double latitude = location.getLatitude();
					double longitude = location.getLongitude();
					
					Toast.makeText(getApplicationContext(), "Konumunuz : \nEnlem " + latitude + "\nBoylam " + longitude, Toast.LENGTH_LONG).show();
				}
				else
				{
					// Konum bilgisi alinamiyorsa mesaj kutusunu goster
					gpsTracker.showSettingsAlert();
				}
			}
		});
	}
}

Hocam çalıştıramadım ben

Layout ve manifest dosyalarını da ekledim gist'e. Manifest dosyanda "ACCESS_COARSE_LOCATION" ve "ACCESS_FINE_LOCATION" izinlerinin bulunması gerekiyor ve çalıştırdığın cihazda ayarlardan uygulamaya konum erişimine izin verilmiş olması gerekiyor.
Yine de çalışmazsa sorun android sürümünde olabilir, 6 yıl önce yazmış olduğum bir kod, yeni versiyonlarda değişiklik yapılan kütüphaneler vs olabilir belki. Kolay gelsin.