UIPopoverPresentationController showing full screen modal popup always

I am trying to show a view controller as UIPopoverPresentationController below the button or in center of window. But it is always showing as full window modal popup.

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    MySecondViewController *controller = [storyboard instantiateViewControllerWithIdentifier:@"Pop"];

    // present the controller
    // on iPad, this will be a Popover
    // on iPhone, this will be an action sheet
    controller.modalPresentationStyle = UINavigationControllerOperationPop;
    [self presentViewController:controller animated:YES completion:nil];
    controller.preferredContentSize = CGSizeMake(280, 230);
    // configure the Popover presentation controller
    UIPopoverPresentationController *popController = [controller popoverPresentationController];
    popController.permittedArrowDirections = UIPopoverArrowDirectionUp;
    popController.delegate = self;

    // in case we don't have a bar button as reference
    popController.sourceView = self.showPop;
    popController.sourceRect = CGRectMake(384, -120, 280, 230);


-(UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller {
    return UIModalPresentationNone;
}

Try this code it is working

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
SecondViewController *controller = [storyboard instantiateViewControllerWithIdentifier:@"pop"];

controller.modalPresentationStyle = UIModalPresentationPopover;
controller.preferredContentSize = CGSizeMake(280, 230);
// configure the Popover presentation controller

controller.popoverPresentationController.delegate = self;
controller.popoverPresentationController.permittedArrowDirections = UIPopoverArrowDirectionUp;


// in case we don't have a bar button as reference
controller.popoverPresentationController.sourceView = self.view;
controller.popoverPresentationController.sourceRect = CGRectMake(384, -120, 280, 230);
//    controller.presentationController.delegate = self;
[self presentViewController:controller animated:YES completion:nil];