Permission helper

    PermissionsHelper helper = new PermissionsHelper(context);

    if(helper.isPermissionGranted(CAMERA))
    {
        //granted
    }else{
       // not granted
    }

    helper.requestPermissions(new String[]{CAMERA}, new PermissionCallback() {
               @Override
               public void onResponseReceived(final HashMap<String, PermissionsHelper.PermissionGrant> mapPermissionGrants) {
                         PermissionsHelper.PermissionGrant permissionGrant = mapPermissionGrants
                                  .get(CAMERA);

                            switch (permissionGrant) {
                                case GRANTED:
                                    //permission has been granted
                                    Toast.makeText(MainActivity.this,"Granted",Toast.LENGTH_SHORT).show();
                                    break;
                                case DENIED:
                                    //permission has been denied
                                    Toast.makeText(MainActivity.this,"Denied",Toast.LENGTH_SHORT).show();
                                    break;
                                case NEVERSHOW:
                                    //permission has been denied and never show has been selected. Open permission settings of the app.
                                    Toast.makeText(MainActivity.this,"Denied with Never show",Toast.LENGTH_SHORT).show();
                                    break;
                            }
                        }
                    });

@Override
public void onRequestPermissionsResult(final int requestCode, @NonNull final String[] permissions, @NonNull final int[] grantResults) {
    helper.onRequestPermissionsResult(permissions, grantResults);
}

    compile 'com.neurenor:permission-helper:1.0.1'