获取Android Studio应用中的当前位置
我正在开发我的第一个Android应用程序，它应该获取Android设备的经度和经度 ，并通过Web服务将其发送到模板文档。
我按照http://developer.android.com/training/location/retrieve-current.html获取位置的指南。
这是我的.java类的代码：
import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.location.Location; import android.location.LocationManager; import android.os.Bundle; import android.provider.Settings; import android.support.v7.app.AlertDialog; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.EditText; import com.google.android.gms.common.ConnectionResult; import com.google.android.gms.common.api.GoogleApiClient; import com.google.android.gms.location.LocationServices; public class GetLocation extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener { private GoogleApiClient mGoogleApiClient; EditText textLat; EditText textLong; EditText lat; EditText lon; protected void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.get_location); textLat = (EditText) findViewById(R.id.latitude); textLong = (EditText) findViewById(R.id.longitude); mGoogleApiClient = new GoogleApiClient.Builder(this) .addConnectionCallbacks(this) .addOnConnectionFailedListener(this) .addApi(LocationServices.API) .build(); } private boolean isGPSEnabled() { LocationManager cm = (LocationManager) getSystemService(Context.LOCATION_SERVICE); return cm.isProviderEnabled(LocationManager.GPS_PROVIDER); } @Override public void onConnected(Bundle bundle) { Location mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient); if (mLastLocation != null) { lat.setText(String.valueOf(mLastLocation.getLatitude())); lon.setText(String.valueOf(mLastLocation.getLongitude())); } } @Override public void onConnectionSuspended(int i) { } @Override public void onConnectionFailed(ConnectionResult connectionResult) { } public void onButtonClick(View v){ if(v.getId() == R.id.getGpsLocation){ if(!isGPSEnabled()){ new AlertDialog.Builder(this) .setMessage("Please activate your GPS Location!") .setCancelable(false) .setPositiveButton("Settings", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS); startActivity(i); } }) .setNegativeButton("Cancel", null) .show(); } else { textLat.setText(String.valueOf(lat)); textLong.setText(String.valueOf(lon)); } } } } 我没有得到任何错误，但是当我点击应该获得坐标的按钮时， 我在两个视图中都得到’null’文本 。
我还包括互联网权限，访问精细和粗略的位置。
提前致谢！
我在恶魔网上写了这个主题的详细教程。您可以在这里找到更多描述，也可以下载整个演示源代码以便更好地理解。
首先，将它放在gradle文件中
compile 'com.google.android.gms:play-services:9.0.2'
然后实现必要的接口
public class MainActivity extends BaseActivitiy implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, com.google.android.gms.location.LocationListener
声明实例
private GoogleApiClient mGoogleApiClient; private Location mLocation; private LocationManager locationManager; private LocationRequest mLocationRequest;
把它放在onCreate()
mGoogleApiClient = new GoogleApiClient.Builder(this) .addConnectionCallbacks(this) .addOnConnectionFailedListener(this) .addApi(LocationServices.API) .build(); locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
最后，重写必要的方法
@Override public void onConnected(Bundle bundle) { if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { // TODO: Consider calling // ActivityCompat#requestPermissions // here to request the missing permissions, and then overriding // public void onRequestPermissionsResult(int requestCode, String[] permissions, // int[] grantResults) // to handle the case where the user grants the permission. See the documentation // for ActivityCompat#requestPermissions for more details. return; } startLocationUpdates(); mLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient); if(mLocation == null){ startLocationUpdates(); } if (mLocation != null) { double latitude = mLocation.getLatitude(); double longitude = mLocation.getLongitude(); } else { // Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show(); } } protected void startLocationUpdates() { // Create the location request mLocationRequest = LocationRequest.create() .setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY) .setInterval(UPDATE_INTERVAL) .setFastestInterval(FASTEST_INTERVAL); // Request location updates if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { // TODO: Consider calling // ActivityCompat#requestPermissions // here to request the missing permissions, and then overriding // public void onRequestPermissionsResult(int requestCode, String[] permissions, // int[] grantResults) // to handle the case where the user grants the permission. See the documentation // for ActivityCompat#requestPermissions for more details. return; } LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this); Log.d("reque", "--->>>>"); } @Override public void onConnectionSuspended(int i) { Log.i(TAG, "Connection Suspended"); mGoogleApiClient.connect(); } @Override public void onConnectionFailed(ConnectionResult connectionResult) { Log.i(TAG, "Connection failed. Error: " + connectionResult.getErrorCode()); } @Override public void onStart() { super.onStart(); mGoogleApiClient.connect(); } @Override public void onStop() { super.onStop(); if (mGoogleApiClient.isConnected()) { mGoogleApiClient.disconnect(); } } @Override public void onLocationChanged(Location location) { }
在运行应用程序之前，请不要忘记在设备中启动GPS。
您需要定义LocationListener。
public class MainActivity extends Activity implements LocationListener{ protected LocationManager locationManager; protected LocationListener locationListener; protected Context context; TextView txtLat; String lat; String provider; protected String latitude,longitude; protected boolean gps_enabled,network_enabled; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); txtLat = (TextView) findViewById(R.id.textview1); locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this); } @Override public void onLocationChanged(Location location) { txtLat = (TextView) findViewById(R.id.textview1); txtLat.setText("Latitude:" + location.getLatitude() + ", Longitude:" + location.getLongitude()); } @Override public void onProviderDisabled(String provider) { Log.d("Latitude","disable"); } @Override public void onProviderEnabled(String provider) { Log.d("Latitude","enable"); } @Override public void onStatusChanged(String provider, int status, Bundle extras) { Log.d("Latitude","status"); } }
并需要给予以下许可：
ACCESS_COARSE_LOCATION ：当我们为我们的Android应用程序使用网络位置提供程序时使用它。
ACCESS_FINE_LOCATION ：它为两个提供商提供权限。
INTERNET ：使用网络提供商必须获得许可。