在清单文件中，我添加了粗略的权限，当我在装有Android 6的设备上运行时，什么也没发生！我尝试了所有方法，但无法获取位置更新…
我究竟做错了什么？
public class MainActivity extends AppCompatActivity implements LocationListener { LocationManager locationManager; String provider; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); provider = locationManager.getBestProvider(new Criteria(), false); 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; } Location location = locationManager.getLastKnownLocation(provider); if (location != null) { Log.i("Location Info", "Location achieved!"); } else { Log.i("Location Info", "No location :("); } } @Override protected void onResume() { super.onResume(); 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; } locationManager.requestLocationUpdates(provider, 400, 1, this); } @Override protected void onPause() { super.onPause(); 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; } locationManager.removeUpdates(this); } @Override public void onLocationChanged(Location location) { Double lat = location.getLatitude(); Double lng = location.getLongitude(); Log.i("Location info: Lat", lat.toString()); Log.i("Location info: Lng", lng.toString()); } @Override public void onStatusChanged(String provider, int status, Bundle extras) { } @Override public void onProviderEnabled(String provider) { } @Override public void onProviderDisabled(String provider) { } public void getLocation(View view) { 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; } Location location = locationManager.getLastKnownLocation(provider); onLocationChanged(location); } }
实际上需要在运行时请求“位置”权限（请注意代码中的说明）。
这是经过测试的有效代码，用于请求“位置”权限。
确保导入android.Manifest：
android.Manifest
import android.Manifest;
然后将此代码放在Activity中：
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99; public boolean checkLocationPermission() { if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) { // Should we show an explanation? if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)) { // Show an explanation to the user *asynchronously* -- don't block // this thread waiting for the user's response! After the user // sees the explanation, try again to request the permission. new AlertDialog.Builder(this) .setTitle(R.string.title_location_permission) .setMessage(R.string.text_location_permission) .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { //Prompt the user once explanation has been shown ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSIONS_REQUEST_LOCATION); } }) .create() .show(); } else { // No explanation needed, we can request the permission. ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSIONS_REQUEST_LOCATION); } return false; } else { return true; } } @Override public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) { switch (requestCode) { case MY_PERMISSIONS_REQUEST_LOCATION: { // If request is cancelled, the result arrays are empty. if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { // permission was granted, yay! Do the // location-related task you need to do. if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { //Request location updates: locationManager.requestLocationUpdates(provider, 400, 1, this); } } else { // permission denied, boo! Disable the // functionality that depends on this permission. } return; } } }
然后在中调用checkLocationPermission()方法onCreate()：
checkLocationPermission()
onCreate()
@Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //......... checkLocationPermission(); }
然后onResume()，您可以使用和onPause()完全按照问题中的说明进行操作。
onResume()
onPause()
这是一个精简版本，更加简洁：
@Override protected void onResume() { super.onResume(); if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { locationManager.requestLocationUpdates(provider, 400, 1, this); } } @Override protected void onPause() { super.onPause(); if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { locationManager.removeUpdates(this); } }
