如何在运行时请求Android位置权限6

Question

在清单文件中，我添加了粗略和细致的权限，并且当我在Android 6设备上运行时，没有任何反应！我尝试 一切，但没有办法获得位置更新...

我做错了什么？

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); 


    } 

} 

Answer 1

您需要在运行时实际请求位置权限（请注意代码中的注释说明此问题）。

这里是测试和工作代码来请求位置权限。

一定要导入android.Manifest：

import android.Manifest; 

然后把这个代码的活动：

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; 
     } 

    } 
} 

然后调用checkLocationPermission()方法onCreate()：

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    //......... 

    checkLocationPermission(); 
} 

然后，您可以使用onResume()和onPause()正如它在问题中一样。

这里是一个浓缩版本，是一个比较干净的：

@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); 
    } 
}