Androidでユーザーの現在地を取得する最も簡単な方法

この例は、Androidでユーザーの現在地を最も簡単な方法で取得する方法を示しています。

ステップ1 − Android Studioで新しいプロジェクトを作成し、[ファイル]⇒[新しいプロジェクト]に移動して、新しいプロジェクトを作成するために必要なすべての詳細を入力します。

ステップ2 −次のコードをres / layout/activity_main.xmlに追加します。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="https://schemas.android.com/apk/res/android"
   xmlns:tools="https://schemas.android.com/tools"
   android:orientation="vertical"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context=".MainActivity">
<TextView
   android:layout_marginTop="20dp"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="Get Current Location and City Name"
   android:textAlignment="center"
   android:layout_centerHorizontal="true"
   android:textSize="20sp" />
<TextView
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:id="@+id/textView"
   android:layout_centerInParent="true"
   android:textSize="16sp"
   android:textStyle="bold"/>
</RelativeLayout>

ステップ3 −Gradleに次の依存関係を追加します

implementation 'com.google.android.gms:play-services-location:17.0.0'

ステップ4 −次のコードをsrc / MainActivity.java

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;
import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.os.Handler;
import android.os.ResultReceiver;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
import com.google.android.gms.location.LocationServices;
public class MainActivity extends AppCompatActivity {
   private FusedLocationProviderClient fusedLocationClient;
   private static final int LOCATION_PERMISSION_REQUEST_CODE = 2;
   private LocationAddressResultReceiver addressResultReceiver;
   private TextView currentAddTv;
   private Location currentLocation;
   private LocationCallback locationCallback;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      addressResultReceiver = new LocationAddressResultReceiver(new Handler());
      currentAddTv = findViewById(R.id.textView);
      fusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
      locationCallback = new LocationCallback() {
         @Override
         public void onLocationResult(LocationResult locationResult) {
            currentLocation = locationResult.getLocations().get(0);
            getAddress();
         }
      };
      startLocationUpdates();
   }
   @SuppressWarnings("MissingPermission")
   private void startLocationUpdates() {
      if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) !=
      PackageManager.PERMISSION_GRANTED) {
         ActivityCompat.requestPermissions(this, new
         String[]{Manifest.permission.ACCESS_FINE_LOCATION},
         LOCATION_PERMISSION_REQUEST_CODE);
      }
      else {
         LocationRequest locationRequest = new LocationRequest();
         locationRequest.setInterval(2000);
         locationRequest.setFastestInterval(1000);
         locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
         fusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
      }
   }
   @SuppressWarnings("MissingPermission")
   private void getAddress() {
      if (!Geocoder.isPresent()) {
         Toast.makeText(MainActivity.this, "Can't find current address, ",
         Toast.LENGTH_SHORT).show();
         return;
      }
      Intent intent = new Intent(this, GetAddressIntentService.class);
      intent.putExtra("add_receiver", addressResultReceiver);
      intent.putExtra("add_location", currentLocation);
      startService(intent);
   }
   @Override
   public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull
int[] grantResults) {
   if (requestCode == LOCATION_PERMISSION_REQUEST_CODE) {
      if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
         startLocationUpdates();
      }
       else {
         Toast.makeText(this, "Location permission not granted, " + "restart the app if you want the
         feature", Toast.LENGTH_SHORT).show();
      }
   }
}
private class LocationAddressResultReceiver extends ResultReceiver {
   LocationAddressResultReceiver(Handler handler) {
      super(handler);
   }
   @Override
   protected void onReceiveResult(int resultCode, Bundle resultData) {
      if (resultCode == 0) {
         Log.d("Address", "Location null retrying");
         getAddress();
      }
      if (resultCode == 1) {
         Toast.makeText(MainActivity.this, "Address not found, ", Toast.LENGTH_SHORT).show();
      }
      String currentAdd = resultData.getString("address_result");
         showResults(currentAdd);
      }
   }
   private void showResults(String currentAdd) {
      currentAddTv.setText(currentAdd);
   }
   @Override
   protected void onResume() {
      super.onResume();
      startLocationUpdates();
   }
   @Override
   protected void onPause() {
      super.onPause();
      fusedLocationClient.removeLocationUpdates(locationCallback);
   }
}

ステップ5 −新しいJavaクラスGetaddressIntentService.javaを作成し、次のコードを追加します

package app.com.sample;
import android.app.IntentService;
import android.content.Intent;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.os.ResultReceiver;
import android.util.Log;
import java.util.List;
import java.util.Locale;
import java.util.Objects;
import androidx.annotation.Nullable;
public class GetAddressIntentService extends IntentService {
   private static final String IDENTIFIER = "GetAddressIntentService";
   private ResultReceiver addressResultReceiver;
   public GetAddressIntentService() {
      super(IDENTIFIER);
   }
   @Override
   protected void onHandleIntent(@Nullable Intent intent) {
      String msg;
      addressResultReceiver = Objects.requireNonNull(intent).getParcelableExtra("add_receiver");
      if (addressResultReceiver == null) {
         Log.e("GetAddressIntentService", "No receiver, not processing the request further");
         return;
      }
      Location location = intent.getParcelableExtra("add_location");
      if (location == null) {
         msg = "No location, can't go further without location";
         sendResultsToReceiver(0, msg);
      return;
   }
   Geocoder geocoder = new Geocoder(this, Locale.getDefault());
   List<Address> addresses = null;
   try {
      addresses = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
   }
   catch (Exception ioException) {
      Log.e("", "Error in getting address for the location");
   }
   if (addresses == null || addresses.size() == 0) {
      msg = "No address found for the location";
      sendResultsToReceiver(1, msg);
   }
   else {
      Address address = addresses.get(0);
      String addressDetails = address.getFeatureName() + "\n" + address.getThoroughfare() + "\n" +
      "Locality: " + address.getLocality() + "\n" + "County: " + address.getSubAdminArea() + "\n" +
      "State: " + address.getAdminArea() + "\n" + "Country: " + address.getCountryName() + "\n" +
      "Postal Code: " + address.getPostalCode() + "\n";
      sendResultsToReceiver(2, addressDetails);
   }
}
private void sendResultsToReceiver(int resultCode, String message) {
   Bundle bundle = new Bundle();
   bundle.putString("address_result", message);
   addressResultReceiver.send(resultCode, bundle);
   }
}

ステップ6 −次のコードをandroidManifest.xmlに追加します

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="https://schemas.android.com/apk/res/android"
   package="app.com.sample">
   <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/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   <service android:name=".GetAddressIntentService" />
</application>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
</manifest>

アプリケーションを実行してみましょう。実際のAndroidモバイルデバイスをコンピューターに接続していると思います。 Android Studioからアプリを実行するには、プロジェクトのアクティビティファイルの1つを開き、[実行]をクリックします ツールバーのアイコン。オプションとしてモバイルデバイスを選択し、デフォルトの画面を表示するモバイルデバイスを確認します-