Android WifiManager getScanResult complains about ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission, although permission is declared

Question

I am developing an application for checking Wi-Fi points.

I get the error "java.lang.SecurityException: ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission is required to get scan results" in wifiManager.getScanResults (), although I already declared these permissions.

Primary activity

public class MainActivity extends AppCompatActivity { WifiManager wifiManager; String[] wifis; WifiReceiver wifiReceiver; ListView wifiListView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); wifiListView = (ListView) findViewById(R.id.wifi_list); wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE); wifiReceiver = new WifiReceiver(); wifiManager.startScan(); } protected void onPause() { unregisterReceiver(wifiReceiver); super.onPause(); } protected void onResume() { registerReceiver(wifiReceiver, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)); super.onResume(); } private class WifiReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { List<ScanResult> wifiScanList = wifiManager.getScanResults(); wifis = new String[wifiScanList.size()]; for (int i = 0; i < wifiScanList.size(); i++) { wifis[i] = wifiScanList.get(i).toString(); } wifiListView.setAdapter(new ArrayAdapter<>(getApplicationContext(), android.R.layout.simple_list_item_1, wifis)); } } 

manifest

 <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.sample"> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" /> <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: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> </application> 

I'm on SDK 6.0

I observed a similar question , but the solution does not apply, since I already announced the permission.

Does anyone know what could be the problem? Thanks.

Answer 1

In Android M, you need to ask for permission, which in PermissionModel is defined as dangerous for the user, before you start using it every time, it is as such:

 private boolean mayRequestLocation() { if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) { return true; } if (checkSelfPermission(ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { return true; } if (shouldShowRequestPermissionRationale(ACCESS_FINE_LOCATION)) { Snackbar.make(mView, R.string.permission_rationale, Snackbar.LENGTH_INDEFINITE) .setAction(android.R.string.ok, new View.OnClickListener() { @Override @TargetApi(Build.VERSION_CODES.M) public void onClick(View v) { requestPermissions(new String[]{ACCESS_FINE_LOCATION}, REQUEST_FINE_LOCATION); } }); } else { requestPermissions(new String[]{ACCESS_FINE_LOCATION}, REQUEST_FINE_LOCATION); } return false; } 

Add this to your activity:

 private static final int REQUEST_FINE_LOCATION=0 

and load it at runtime:

 loadPermissions(Manifest.permission.ACCESS_FINE_LOCATION,REQUEST_FINE_LOCATION); 

To evaluate the results of your permission request, you can override the onRequestPermissionsResult method:

 @Override public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) { switch (requestCode) { case REQUEST_FINE_LOCATION: { // If request is cancelled, the result arrays are empty. if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { // The requested permission is granted. } else{ // The user disallowed the requested permission. } return; } } 

Answer 2

MADAO is right : you must enable GPS to get a list of WIFI access points.

But I'm not sure about PEERS_MAC_ADDRESS. If you look at the source code (line 957):

 /** * Return the results of the most recent access point scan, in the form of * a list of {@link ScanResult} objects. * @return the list of results */ public List<ScanResult> getScanResults(String callingPackage) { enforceAccessPermission(); int userId = UserHandle.getCallingUserId(); int uid = Binder.getCallingUid(); boolean canReadPeerMacAddresses = checkPeersMacAddress(); boolean isActiveNetworkScorer = NetworkScorerAppManager.isCallerActiveScorer(mContext, uid); boolean hasInteractUsersFull = checkInteractAcrossUsersFull(); long ident = Binder.clearCallingIdentity(); try { if (!canReadPeerMacAddresses && !isActiveNetworkScorer && !isLocationEnabled()) { return new ArrayList<ScanResult>(); } if (!canReadPeerMacAddresses && !isActiveNetworkScorer && !checkCallerCanAccessScanResults(callingPackage, uid)) { return new ArrayList<ScanResult>(); } if (mAppOps.noteOp(AppOpsManager.OP_WIFI_SCAN, uid, callingPackage) != AppOpsManager.MODE_ALLOWED) { return new ArrayList<ScanResult>(); } if (!isCurrentProfile(userId) && !hasInteractUsersFull) { return new ArrayList<ScanResult>(); } return mWifiStateMachine.syncGetScanResultsList(); } finally { Binder.restoreCallingIdentity(ident); } } 

The first if checks canReadPeerMacAddresses , for which the code is checkPeersMacAddress() :

 /** * Returns true if the caller holds PEERS_MAC_ADDRESS. */ private boolean checkPeersMacAddress() { return mContext.checkCallingOrSelfPermission( android.Manifest.permission.PEERS_MAC_ADDRESS) == PackageManager.PERMISSION_GRANTED; } 

If you add permission, you can bypass if (!canReadPeerMacAddresses && !isActiveNetworkScorer && !isLocationEnabled()) { . I tested, but I can not get the WIFI MAC list, just using permission and turning off the location.

Answer 3

ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION . To get a reliable result, you also need to turn on GPS or get PEERS_MAC_ADDRESS permission, such as Setting .