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javaandroidandroid-wifiwifimanager

Android WifiManager getScanResult complains Need ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission although declared permission


I am developing an App to check Wifi points.

I am getting error "java.lang.SecurityException: Need ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission to get scan results" at wifiManager.getScanResults() even though I already declared those permissions.

main 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 am on SDK 6.0

I observed similar question, but solution does not apply since I already declared permission.

Anyone know what might be problem? Thank you.


Solution

  • In Android M, you need to ask for the permission which is defined as dangerous in PermissionModel to the user before start using each time, it 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 during runtime with:

    loadPermissions(Manifest.permission.ACCESS_FINE_LOCATION,REQUEST_FINE_LOCATION);
    

    To evaluate the results of your permission request, you can override 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;
            }
    
    }