UIPopoverController' is deprecated: first deprecated in iOS 9.0

I know this question have been asked before and I have checked the answers but still have problems. I need to update my XCODE game, which is written in Objective-C to keep it in AppStore, and i have not actively touched OBC for quite a few years now. I have been able to fix all the other issues except the UIPopoverController issue.

I have marked the Warnings with ">" in the code.

I would really appreciate some help here.

I have the following code:

#import "DetailViewController.h"

@interface DetailViewController ()

>>@property (strong, nonatomic) UIPopoverController *masterPopoverController;


- (void)configureView;
@end

@implementation DetailViewController

@synthesize detailItem = _detailItem;
@synthesize detailDescriptionLabel = _detailDescriptionLabel;
>>@synthesize masterPopoverController = _masterPopoverController;

#pragma mark - Managing the detail item

- (void)setDetailItem:(id)newDetailItem
{
if (_detailItem != newDetailItem) {
    _detailItem = newDetailItem;

    // Update the view.
    [self configureView];
}

>>if (self.masterPopoverController != nil) {
>>    [self.masterPopoverController dismissPopoverAnimated:YES];
>>}        
}

- (void)configureView
{
// Update the user interface for the detail item.

if (self.detailItem) {
    self.detailDescriptionLabel.text = [[self.detailItem valueForKey:@"timeStamp"] description];
}
}

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
[self configureView];
}

- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
self.detailDescriptionLabel = nil;
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
} else {
    return YES;
}
}

#pragma mark - Split view

>>- (void)splitViewController:(UISplitViewController *)splitController willHideViewController:(UIViewController *)viewController withBarButtonItem:(UIBarButtonItem *)barButtonItem forPopoverController:(UIPopoverController *)popoverController
{
barButtonItem.title = NSLocalizedString(@"Master", @"Master");
[self.navigationItem setLeftBarButtonItem:barButtonItem animated:YES];
self.masterPopoverController = popoverController;
}

- (void)splitViewController:(UISplitViewController *)splitController willShowViewController:(UIViewController *)viewController invalidatingBarButtonItem:(UIBarButtonItem *)barButtonItem
{
// Called when the view is shown again in the split view, invalidating the button and popover controller.
[self.navigationItem setLeftBarButtonItem:nil animated:YES];
>>self.masterPopoverController = nil;
}

@end