RunTime Permissions in Android M

AndroidRunTimePermissions.java

package application.arkthepro.com.samplebluetoothapp;
import android.Manifest;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
public class MainActivity extends AppCompatActivity {
    private static final int MY_PERMISSIONS_REQUEST =100 ;
    private static final int REQUEST_OPEN_SETTINGS =007 ;
    String TAG = "RESULT";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        CheckAllPermissions();
    }
    public void CheckAllPermissions(){
         boolean isContactPermissionGranted=checkPermissions(Manifest.permission.READ_CONTACTS);
         boolean isLocationPermissionGranted=checkPermissions(Manifest.permission.ACCESS_COARSE_LOCATION);
         boolean isBluetoothPermissionGranted=checkPermissions(Manifest.permission.BLUETOOTH);
        if(isContactPermissionGranted&&isLocationPermissionGranted&&isBluetoothPermissionGranted){
            //All Permissions Granted Do What You want
            Log.i(TAG, "-------------------------User Granted All Permissions ");
        }else {
            //Some Permission were Denied Request Permissions from User
            Log.e(TAG, "-------------------------Asking for Permissions ");
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.READ_CONTACTS,
                            Manifest.permission.ACCESS_COARSE_LOCATION
                    }, MY_PERMISSIONS_REQUEST);
        }


    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        Log.d(TAG, "--------------------------------onRequestPermissionsResult"+permissions[0]+" ="+grantResults[0]);
        Log.d(TAG, "--------------------------------onRequestPermissionsResult"+permissions[1]+" ="+grantResults[1]);
        for(int i:grantResults){
            if(i!=0){
               ShowAlert("With out Required Permissions we can't Proceed.Please Enable Req Permissions in App Setting ");
              break;
            }
        }
/*
//Customized Message for Each Permission
        if(grantResults[0]!=0){
            ShowAlert("To Access Contact Details You need to enable the Contact Related Permission in Settings ");
        }else if(grantResults[1]!=0) {
           ShowAlert("To Access Location Details You need to enable the Location Permission in Settings ");
        }else {
            Log.i(TAG, "-------------------------User Granted All Permissions ");
        }
*/
  }

    public boolean checkPermissions(String per){
        boolean result= true;
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
            int check=checkSelfPermission(per);
            result = check == PackageManager.PERMISSION_GRANTED;
            Log.i(TAG, "----------------------Checking RunTime Permissions Since the Device VERSION_CODE >= M :" + result);
            return result;
        }else {
            Log.i(TAG, "----------------------No Need of RunTime Permissions for Devices with VERSION_CODE < M"+result);
            return result;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch (requestCode){
            case 007:
            {
                CheckAllPermissions();
                break;
            }    }
    }


    public void ShowAlert(String msg){
        AlertDialog alertDialog = new AlertDialog.Builder(
                MainActivity.this).create();
        // Setting Dialog Title
        alertDialog.setTitle("Please Enable Location Permissions");
        // Setting Dialog Message
        alertDialog.setMessage(msg);
        // Setting Icon to Dialog
        // alertDialog.setIcon(R.draw);
        // Setting OK Button
        alertDialog.setButton("Open Settings", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
                // Write your code here to execute after dialog closed
                startActivityForResult(new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + BuildConfig.APPLICATION_ID)), REQUEST_OPEN_SETTINGS);
            }
        });
  // Showing Alert Message
        alertDialog.show();


    }
}