ANDROID MULTIPAL RUNTIME PERMISSION:

Think of a scenario where you might need to ask for multiple permissions. For this, instead of requesting multiple permissions in multiple dialogs, we can prompt all the permissions in a single dialog where permissions will be scrolled through one after another.

eg:
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

Step 1: We checked for multiple permission with checkSelfPermission() similar as Single permission.

if(ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[0]) != PackageManager.PERMISSION_GRANTED

                        || ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[1]) != PackageManager.PERMISSION_GRANTED

                        || ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[2]) != PackageManager.PERMISSION_GRANTED){

..............

}

else{

.............

}

Step 2: We used shouldShowRequestPermissionRationale() method to check if we should show the explanation for the permission or not similar as single permission.

if(ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[0])

                            || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[1])

                            || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[2])){

}

Now, how we achieve this is by creating string array with required permissions. While checking for permissions, checked by all elements of the array. The only exception is in while checking with SharedPreferences, here we’ve checked with only the first string, the reason is that for storing shared preferences on string is enough and only one shared preference can tell us whether we’ve already requested for permissions or not (as we are requesting for all permissions in one go).

In the onRequestPermissionsResult() method we used a for loop to determine whether all permissions are granted or not. If a single permission is not granted then we will not proceed further.

Just like: 

 @Override

    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {

        super.onRequestPermissionsResult(requestCode, permissions, grantResults);

        if(requestCode == PERMISSION_CALLBACK_CONSTANT){

            //check if all permissions are granted

            boolean allgranted = false;

            for(int i=0;i<grantResults.length;i++){

                if(grantResults[i]==PackageManager.PERMISSION_GRANTED){

                    allgranted = true;

                } else {

                    allgranted = false;

                    break;

                }

            }

            if(allgranted){

                proceedAfterPermission();

            }

FINAL CODE:
public class MultiplePermissionsActivity extends AppCompatActivity {

    private static final int PERMISSION_CALLBACK_CONSTANT = 100;
    private static final int REQUEST_PERMISSION_SETTING = 101;
    String[] permissionsRequired = new String[]{Manifest.permission.CAMERA,
            Manifest.permission.ACCESS_FINE_LOCATION,
            Manifest.permission.ACCESS_COARSE_LOCATION};
    private TextView txtPermissions;
    private Button btnCheckPermissions;
    private SharedPreferences permissionStatus;
    private boolean sentToSettings = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_multiple_permissions);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        permissionStatus = getSharedPreferences("permissionStatus",MODE_PRIVATE);

        txtPermissions = (TextView) findViewById(R.id.txtPermissions);
        btnCheckPermissions = (Button) findViewById(R.id.btnCheckPermissions);

        btnCheckPermissions.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[0]) != PackageManager.PERMISSION_GRANTED
                        || ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[1]) != PackageManager.PERMISSION_GRANTED
                        || ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[2]) != PackageManager.PERMISSION_GRANTED){
                    if(ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[0])
                            || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[1])
                            || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[2])){
                        //Show Information about why you need the permission
                        AlertDialog.Builder builder = new AlertDialog.Builder(MultiplePermissionsActivity.this);
                        builder.setTitle("Need Multiple Permissions");
                        builder.setMessage("This app needs Camera and Location permissions.");
                        builder.setPositiveButton("Grant", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.cancel();
                                ActivityCompat.requestPermissions(MultiplePermissionsActivity.this,permissionsRequired,PERMISSION_CALLBACK_CONSTANT);
                            }
                        });
                        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.cancel();
                            }
                        });
                        builder.show();
                    } else if (permissionStatus.getBoolean(permissionsRequired[0],false)) {
                        //Previously Permission Request was cancelled with 'Dont Ask Again',
                        // Redirect to Settings after showing Information about why you need the permission
                        AlertDialog.Builder builder = new AlertDialog.Builder(MultiplePermissionsActivity.this);
                        builder.setTitle("Need Multiple Permissions");
                        builder.setMessage("This app needs Camera and Location permissions.");
                        builder.setPositiveButton("Grant", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.cancel();
                                sentToSettings = true;
                                Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                                Uri uri = Uri.fromParts("package", getPackageName(), null);
                                intent.setData(uri);
                                startActivityForResult(intent, REQUEST_PERMISSION_SETTING);
                                Toast.makeText(getBaseContext(), "Go to Permissions to Grant  Camera and Location", Toast.LENGTH_LONG).show();
                            }
                        });
                        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.cancel();
                            }
                        });
                        builder.show();
                    }  else {
                        //just request the permission
                        ActivityCompat.requestPermissions(MultiplePermissionsActivity.this,permissionsRequired,PERMISSION_CALLBACK_CONSTANT);
                    }

                    txtPermissions.setText("Permissions Required");

                    SharedPreferences.Editor editor = permissionStatus.edit();
                    editor.putBoolean(permissionsRequired[0],true);
                    editor.commit();
                } else {
                    //You already have the permission, just go ahead.
                    proceedAfterPermission();
                }
            }
        });
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == PERMISSION_CALLBACK_CONSTANT){
            //check if all permissions are granted
            boolean allgranted = false;
            for(int i=0;i<grantResults.length;i++){
                if(grantResults[i]==PackageManager.PERMISSION_GRANTED){
                    allgranted = true;
                } else {
                    allgranted = false;
                    break;
                }
            }

            if(allgranted){
                proceedAfterPermission();
            } else if(ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[0])
                    || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[1])
                    || ActivityCompat.shouldShowRequestPermissionRationale(MultiplePermissionsActivity.this,permissionsRequired[2])){
                txtPermissions.setText("Permissions Required");
                AlertDialog.Builder builder = new AlertDialog.Builder(MultiplePermissionsActivity.this);
                builder.setTitle("Need Multiple Permissions");
                builder.setMessage("This app needs Camera and Location permissions.");
                builder.setPositiveButton("Grant", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                        ActivityCompat.requestPermissions(MultiplePermissionsActivity.this,permissionsRequired,PERMISSION_CALLBACK_CONSTANT);
                    }
                });
                builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                    }
                });
                builder.show();
            } else {
                Toast.makeText(getBaseContext(),"Unable to get Permission",Toast.LENGTH_LONG).show();
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_PERMISSION_SETTING) {
            if (ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[0]) == PackageManager.PERMISSION_GRANTED) {
                //Got Permission
                proceedAfterPermission();
            }
        }
    }

    private void proceedAfterPermission() {
        txtPermissions.setText("We've got all permissions");
        Toast.makeText(getBaseContext(), "We got All Permissions", Toast.LENGTH_LONG).show();
    }

    @Override
    protected void onPostResume() {
        super.onPostResume();
        if (sentToSettings) {
            if (ActivityCompat.checkSelfPermission(MultiplePermissionsActivity.this, permissionsRequired[0]) == PackageManager.PERMISSION_GRANTED) {
                //Got Permission
                proceedAfterPermission();
            }
        }
    }

}


Writer : Stuti Kasliwal