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WifiManeger#scanResults() always returning empty in Android 6.0

Yes, I did take a look at all other similar question but they are not working for me. I'm trying to scan all the access points near me. This exact code works for Android 10, but in Android 6.0, specifically in Galaxy J5, the getScanResult() is always returning empty, the code:
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_lista_alunos);
setTitle(TITULO_APPBAR);
listaAlunosView = new ListaAlunosView(this);
configuraFabNovoAluno();
configuraLista();
wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
//Check for permissions
if ((ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
!= PackageManager.PERMISSION_GRANTED)
|| (ContextCompat.checkSelfPermission(this, Manifest.permission.CHANGE_WIFI_STATE)
!= PackageManager.PERMISSION_GRANTED))
{
Log.i("TAG", "Requesting permissions");
//Request permission
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.ACCESS_FINE_LOCATION,
Manifest.permission.ACCESS_WIFI_STATE,
Manifest.permission.CHANGE_WIFI_STATE,
Manifest.permission.ACCESS_NETWORK_STATE},
123);
}
else
Log.i("TAG", "Permissions already granted");
wifiScan();
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
Log.i("TAG,", "onRequestPermissionsResult");
switch (requestCode)
{
case 123:
{
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED)
{
// permission was granted
Log.i("TAG", "permission granted: " + permissions[0]);
}
else
{
// permission denied, boo! Disable the
// functionality that depends on this permission.
Log.i("TAG", "permission denied: " + permissions[0]);
}
return;
}
// other 'case' lines to check for other
// permissions this app might request.
}
}
private void wifiScan() {
wifiManager.startScan();
BroadcastReceiver wifiScanReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
boolean success = intent.getBooleanExtra(WifiManager.EXTRA_RESULTS_UPDATED, false);
if(success) {
List<ScanResult> scanResults = wifiManager.getScanResults();
Log.i("SCAN RESULT:", "" + scanResults);
} else {
}
}
};
Android Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="br.com.alura.agenda"
tools:ignore="GoogleAppIndexingWarning">
<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_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme"
tools:ignore="AllowBackup">
<activity android:name=".ui.activity.ListaAlunosActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ui.activity.FormularioAlunoActivity" />
</application>
</manifest>
I also turned my Location Services ON.
Can someone tell me where is the error?

storage permissions not being asked

I have added to the manifest files these permissions
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-feature android:name="android.hardware.location.gps" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
But when the user installs the app the only permission he is being asked and allows is location.
I also want to ask the user for storage permission.How is this possible?

Use runtime permission code where you add the data inside the internal storage. You can use dexture or easy permission lib for this.

Have you tried what the Android documentation points out:
// Here, thisActivity is the current activity
if (ContextCompat.checkSelfPermission(thisActivity,
Manifest.permission.READ_CONTACTS)
!= PackageManager.PERMISSION_GRANTED) {
// Permission is not granted
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(thisActivity,
Manifest.permission.READ_CONTACTS)) {
// 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.
} else {
// No explanation needed; request the permission
ActivityCompat.requestPermissions(thisActivity,
new String[]{Manifest.permission.READ_CONTACTS},
MY_PERMISSIONS_REQUEST_READ_CONTACTS);
// MY_PERMISSIONS_REQUEST_READ_CONTACTS is an
// app-defined int constant. The callback method gets the
// result of the request.
}
} else {
// Permission has already been granted
}
https://developer.android.com/training/permissions/requesting#java

For "dangerous" permissions (includes Storage, Location, Camera, Calendar and more), you need to request the user for their permission not at installation, but when it's required.
It's important that you check every time the permission is required, because the user can revoke the permission anytime.
To check for permission (in Kotlin) (in this example it's FINE_LOCATION, change it to whatever permission you need to request):
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED
) {
//if permission not granted, start function to request permission
//MY_PERMISSIONS_REQUEST is the requestCode, an int > 0
ActivityCompat.requestPermissions(
this,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
MY_PERMISSIONS_REQUEST
)
}
and then then override the onRequestPermissionsResult function:
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<String>, grantResults: IntArray
) {
when (requestCode) {
MY_PERMISSIONS_REQUEST -> {
// If request is cancelled, the result arrays are empty.
if ((grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED)) {
//granted - you are not able to use Location Functionality
} else {
// permission denied
Toast.makeText(this, "Location Functionality Disabled.", Toast.LENGTH_LONG).show()
}
return
}
// Add other 'when' lines to check for other
// permissions this app might request.
else -> {
// Ignore all other requests.
}
}
}
You can also request multiple permissions at once.
Android 6.0 multiple permissions

Android: How to make a default dialer app?

Today I got a rejection from Google for my app Facetocall
Your app does not appear to prompt the user to be a default handler prior to requesting related permissions as required by the policy.
Please make necessary changes in order to comply with policy
requirements and resubmit your app through a Declaration Form.
Default handler capability was listed on your declaration form, but your app has no default handler capability.
My goal is to make a default dialer app.
Here is my Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.gazman.beep"
android:installLocation="preferExternal">
<uses-permission android:name="android.permission.CALL_PHONE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.READ_CALL_LOG" />
<uses-permission android:name="android.permission.WRITE_CALL_LOG" />
<uses-permission android:name="android.permission.SEND_SMS" />
... and other permissions
<application
android:name=".application.BeepApp"
android:allowBackup="false"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
tools:ignore="GoogleAppIndexingWarning">
<activity
android:name=".system_intents.IntentsActivity"
android:launchMode="singleTask"
android:noHistory="true"
android:theme="#style/Theme.Transparent">
<intent-filter>
<action android:name="android.intent.action.DIAL" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.DIAL" />
<category android:name="android.intent.category.DEFAULT" />
<data android:scheme="tel" />
</intent-filter>
</activity>
<activity
android:name=".call.CallActivity"
android:launchMode="singleTop"
android:screenOrientation="portrait"
android:showForAllUsers="true" />
<service
android:name="com.gazman.beep.call.MyInCallService"
android:permission="android.permission.BIND_INCALL_SERVICE">
<meta-data
android:name="android.telecom.IN_CALL_SERVICE_UI"
android:value="true" />
<intent-filter>
<action android:name="android.telecom.InCallService" />
</intent-filter>
</service>
... And other declarations
</application>
</manifest>
And here is what I do when my app launches:
private void checkDefaultHandler() {
if (isAlreadyDefaultDialer()) {
return;
}
Intent intent = new Intent(TelecomManager.ACTION_CHANGE_DEFAULT_DIALER);
intent.putExtra(TelecomManager.EXTRA_CHANGE_DEFAULT_DIALER_PACKAGE_NAME, getPackageName());
if (intent.resolveActivity(getPackageManager()) != null) {
startActivityForResult(intent, REQUEST_CODE_SET_DEFAULT_DIALER);
}
else{
throw new RuntimeException("Default phone functionality not found");
}
}
private boolean isAlreadyDefaultDialer() {
TelecomManager telecomManager = (TelecomManager) getSystemService(TELECOM_SERVICE);
return getPackageName().equals(telecomManager.getDefaultDialerPackage());
}
What am I missing here?
I tried submitting the form again and this time I add a video that shows my app on an emulator(I see the same behavior on all the real devices too) here is the reply that I got back:
Your app does not appear to prompt the user to be a default handler prior to requesting related permissions as required by the policy.
Please make necessary changes in order to comply with policy
requirements and resubmit your app through a Declaration Form.

to make default dialer app, you need to do 2 things :
1. add the following permissions in your android manifest
<activity>
<intent-filter>
<action android:name="android.intent.action.DIAL"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</activity>
actually performing the check :
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.main_layout)
...
checkDefaultDialer()
...
}
const val REQUEST_CODE_SET_DEFAULT_DIALER=200
private fun checkDefaultDialer() {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M)
return
val telecomManager = getSystemService(TELECOM_SERVICE) as TelecomManager
val isAlreadyDefaultDialer = packageName == telecomManager.defaultDialerPackage
if (isAlreadyDefaultDialer)
return
val intent = Intent(TelecomManager.ACTION_CHANGE_DEFAULT_DIALER)
.putExtra(TelecomManager.EXTRA_CHANGE_DEFAULT_DIALER_PACKAGE_NAME, packageName)
startActivityForResult(intent, REQUEST_CODE_SET_DEFAULT_DIALER)
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
when (requestCode) {
REQUEST_CODE_SET_DEFAULT_DIALER -> checkSetDefaultDialerResult(resultCode)
}
}
private fun checkSetDefaultDialerResult(resultCode: Int) {
val message = when (resultCode) {
RESULT_OK -> "User accepted request to become default dialer"
RESULT_CANCELED -> "User declined request to become default dialer"
else -> "Unexpected result code $resultCode"
}
Toast.makeText(this, message, Toast.LENGTH_SHORT).show()
}

You don't need to panic. This kind of conversation happened with me also, regarding AdMob content on my app. I declared everything perfectly but still they were saying content rating not fine due to type of Ads my app was showing. When more mails exchanged they sent me screenshot with the proof of wrong Ads, so finally i checked my whole code again and found my mistake.
The point here is that Google is good at what they do, and if they said so, then your app lacks something.
To be very honest, your app did not ask the user anywhere to allow it to be set as default, instead it set itself default in the background. You should ask for every permission required by your app that are critical and can be used by any app or virus or spyware to interfere with user privacy.
You can do that with a function like in the following example, which is asking for Camera permission from the user:
private void requestCameraPermission() {
Log.i(TAG, "CAMERA permission has NOT been granted. Requesting permission.");
// BEGIN_INCLUDE(camera_permission_request)
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.CAMERA)) {
// Provide an additional rationale to the user if the permission was not granted
// and the user would benefit from additional context for the use of the permission.
// For example if the user has previously denied the permission.
Log.i(TAG,
"Displaying camera permission rationale to provide additional context.");
Snackbar.make(mLayout, R.string.permission_camera_rationale,
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, new View.OnClickListener() {
#Override
public void onClick(View view) {
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.CAMERA},
REQUEST_CAMERA);
}
})
.show();
} else {
// Camera permission has not been granted yet. Request it directly.
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},
REQUEST_CAMERA);
}
// END_INCLUDE(camera_permission_request)
}
You can see the complete repository at Google Samples
And don't worry. If you rectify this problem, they will accept your application, as they did for mine.

in case anyone comes cross this post . . .
I used this for asking the user for changing the default dailer.
Know that the there gonna be 2 windows prompting(for me it was fine).
private void setDefaultDialer()
{
AlertDialog.Builder builder;
builder = new AlertDialog.Builder(this);
builder.setMessage("Do you want to make Cricket your default Dialer?(it will not cover or replace your dialer)")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
defaultDialerPackage = "cricket";
Intent intent = new Intent(TelecomManager.ACTION_CHANGE_DEFAULT_DIALER);
startActivityForResult(intent.putExtra(TelecomManager.EXTRA_CHANGE_DEFAULT_DIALER_PACKAGE_NAME,getPackageName()),REQUEST_CODE_SET_DEFAULT_DIALER);
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
Toast.makeText(getApplicationContext(),"Cancelled - No action was taken",
Toast.LENGTH_SHORT).show();
}
});
AlertDialog alert = builder.create();
alert.setTitle("Cricket need default dialer permission!!");
alert.show();
}

WifiManger.getScanResults() returns empty list on android

Yes, I did take a look at all other similar question but they are not working for me.
I am trying to get a list of wifi connections available near me.
This is how I am doing it:
public class WifiFunction {
private final String tag = WifiFunction.class.getSimpleName();
private WifiManager wifiManager;
public List<WifiDetail> getListofWifi(Context context) {
List<WifiDetail> wifiDetails = new ArrayList<>();
List<ScanResult> results = wifiManager.getScanResults();
Log.d(tag,"Wifi Details " + wifiManager.getScanResults().size());
for (ScanResult result : results) {
wifiDetails.add(new WifiDetail(result.BSSID, result.SSID));
Log.d(tag, result.BSSID + result.SSID);
}
return wifiDetails;
}
public void startScan(Context context)
{
wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
wifiManager.startScan();
IntentFilter filter = new IntentFilter();
filter.addAction(SCAN_RESULTS_AVAILABLE_ACTION);
context.registerReceiver(new resultReciever(this),filter);
}
}
Receiver class :
public class resultReciever extends BroadcastReceiver {
private WifiFunction wifiFunction;
resultReciever(WifiFunction wifiFunction)
{
this.wifiFunction = wifiFunction;
}
#Override
public void onReceive(Context context, Intent intent) {
Log.d("Receiver","started");
wifiFunction.getListofWifi(context);
}
}
From Main Activity I am just calling:
(new WifiFunction()).startScan(this);
that is after checking for permissions.
Yes, I did declare receiver in the manifest.
I am asking for access and change of wifi state and access coarse location.
Still, Log prints the size of the returned list to be 0. What am I doing wrong? How to solve it?
Edit: Manifest
<?xml version="1.0" encoding="utf-8"?>
<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_NETWORK_STATE" />
<uses-permission android:name="android.permisiion.ACCESS_COARSE_LOCATION" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
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>
<receiver android:name=".resultReciever"/>
</application>
EDIT 2:
Runtime Permission:
private boolean checkPermission() {
List<String> permissionsList = new ArrayList<String>();
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_WIFI_STATE) != PackageManager.PERMISSION_GRANTED) {
permissionsList.add(Manifest.permission.ACCESS_WIFI_STATE);
}
if (ContextCompat.checkSelfPermission(this, Manifest.permission.CHANGE_WIFI_STATE) != PackageManager.PERMISSION_GRANTED) {
permissionsList.add(Manifest.permission.CHANGE_WIFI_STATE);
}
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
permissionsList.add(Manifest.permission.ACCESS_COARSE_LOCATION);
}
if (permissionsList.size() > 0) {
ActivityCompat.requestPermissions(this, permissionsList.toArray(new String[permissionsList.size()]),
1);
return false;
}
return true;
}
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions,
int[] grantResults) {
switch (requestCode) {
case 1:
(new WifiFunction()).startScan(this);
break;
}
}

This worked. I just had to give Access_Fine_Location permission.

Adding the following line to your manifest is not necessarily enough to fix the problem!
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
If your targetSdkVersion is 23 or greater, then (because this is one of the dangerous permissions) you must also do something like this
ActivityCompat.requestPermissions(Main.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION }, 1);
Doing this fixed the problem for both me and the OP. I double-checked the assertion by reversing the changes to recreate the problem.
NB: There are 2 highly remarkable elements here:
(1) Nowhere is it documented that WifiManager.startScan() requires this permission.
(2) My app is based on a working (pre-API 23) app that does NOT have Manifest.permission.ACCESS_FINE_LOCATION

You were missing permission to access Access_Fine_Location, but starting from Android 6 granting all the permissions won't yield the expected output. You have to enable location services in order to get desired results. Granting permissions is just the half work done.
You can also fire an intent to redirect user to this setting:
Intent myIntent = new Intent( Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(myIntent);
Location services are necessary because when you access the scan results, you can access the information like BSSID (address of the access point). This information can also be used to detect the location of device. By requiring location services, OS ensures that user understands their location information is being accessed when they use your app.

Set permission in your AndroidManifest.xml
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Now go to settings > Apps > your app > Permissions. Make sure Location is switched on.
Now go to Settings > Location make sure its switched on.
You should be able to get results in WifiManger.getScanResults()

A successful call to WifiManager.getScanResults() requires any one of the following permissions:
ACCESS_FINE_LOCATION
ACCESS_COARSE_LOCATION
CHANGE_WIFI_STATE
If the calling app does not have any of these permissions, the call fails with a SecurityException.
So Android 8 able to retrive all wifi APs by just enabling the CHANGE_WIFI_STATE

MediaStore permission denied error android

I am trying to access mp3 files in externalStorage and this is my code:
public class MainActivity extends AppCompatActivity {
private LinearLayout viewL;
private String[] STAR = { "*" };
String fullpath;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewL = (LinearLayout) findViewById(R.id.linear);
try{
String provider = "com.android.providers.media.MediaProvider";
Uri uri = Uri.parse("content://media/external/audio/media");
grantUriPermission(provider, uri, Intent.FLAG_GRANT_READ_URI_PERMISSION);
grantUriPermission(provider, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
grantUriPermission(provider, uri, Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION);
Cursor cursor;
Uri allsongsuri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
String selection = android.provider.MediaStore.Audio.Media.IS_MUSIC + " != 0";
cursor = getContentResolver().query(allsongsuri, STAR, selection, null, null);
for(int i =0;i<1;i++){
cursor.moveToFirst();
fullpath = cursor.getString(cursor
.getColumnIndex(MediaStore.Audio.Media.DATA));
}
MediaPlayer mp = new MediaPlayer();
Uri myUri = Uri.parse(fullpath);
mp.setDataSource(this,myUri);
mp.prepare();
mp.start();
}
catch (Exception e){
Snackbar.make(viewL,e.toString(),Snackbar.LENGTH_LONG).show();
}
}
}
This is my manifestFile:
<?xml version="1.0" encoding="utf-8"?>
<manifest package="com.grassa"
xmlns:android="http://schemas.android.com/apk/res/android">
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.STORAGE" />
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS" />
<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"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
</manifest>
This is my logcat:
Writing exception to parcel
java.lang.SecurityException: Permission Denial: reading com.android.providers.media.MediaProvider uri content://media/external/audio/media from pid=20241, uid=10113 requires android.permission.READ_EXTERNAL_STORAGE, or grantUriPermission()
at android.content.ContentProvider.enforceReadPermissionInner(ContentProvider.java:605)
at android.content.ContentProvider$Transport.enforceReadPermission(ContentProvider.java:480)
at android.content.ContentProvider$Transport.query(ContentProvider.java:211)
at android.content.ContentProviderNative.onTransact(ContentProviderNative.java:112)
at android.os.Binder.execTransact(Binder.java:453)
As you can see i have added all the permissions required but still I am getting permission Denied error Can someone help me out with this?? ThankYou

If you are running it on marshmallow, you need to request the permission at the runtime.
Here's the official doc : http://developer.android.com/training/permissions/requesting.html
You have to check the permission using ContextCompat.checkSelfPermission function. Then, if you don't have the permission,
request it via ActivityCompat.requestPermissions method and implement
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) method to receive the user results.

If the device is running Android 5.1 or lower, or your app's target SDK is 22 or lower: If you list a dangerous permission in your manifest, the user has to grant the permission when they install the app; if they do not grant the permission, the system does not install the app at all.
If the device is running Android 6.0 or higher, and your app's target SDK is 23 or higher: The app has to list the permissions in the manifest, and it must request each dangerous permission it needs while the app is running. The user can grant or deny each permission, and the app can continue to run with limited capabilities even if the user denies a permission request.
use below code,
if (ContextCompat.checkSelfPermission(thisActivity,
Manifest.permission.READ_CONTACTS)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(thisActivity,
Manifest.permission.READ_CONTACTS)) {
// Show an expanation 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.
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(thisActivity,
new String[]{Manifest.permission.READ_CONTACTS},
MY_PERMISSIONS_REQUEST_READ_CONTACTS);
// MY_PERMISSIONS_REQUEST_READ_CONTACTS is an
// app-defined int constant. The callback method gets the
// result of the request.
}
}
and handle you permission status by,
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_READ_CONTACTS: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// contacts-related task you need to do.
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
Source : http://developer.android.com/training/permissions/requesting.html