how to fix my UI button which freezes when I tap it?

- (IBAction)btnMenuTapped:(id)sender
{
    if (self.popoverController)
    {
        [self.popoverController dismissPopoverAnimated:YES];
        self.popoverController = nil;
    }
    else
    {
        MainMenuViewController *contentViewController = [[MainMenuViewController alloc] initWithNibName:@"MainMenuViewController" bundle:nil];
        contentViewController.delegate = self;
        self.popoverController = [[WEPopoverController alloc] initWithContentViewController:contentViewController];
        self.popoverController.delegate = self;
        self.popoverController.popoverContentSize = contentViewController.view.frame.size;

        [self.popoverController presentPopoverFromRect:[sender frame]
                                                inView:self.view
                              permittedArrowDirections:UIPopoverArrowDirectionDown
                                              animated:YES];

    }
}

@interface MainViewController : UIViewController <LoginDelegate,WEPopoverParentView,PopoverControllerDelegate,MainMenuDelegate,MKMapViewDelegate,UIActionSheetDelegate,UIAccelerometerDelegate, CLLocationManagerDelegate, NSObject>
{
    AppDelegate *appDelegate;
    IBOutlet MKMapView *userMap;
    CLLocationManager *locationManager;

}
@property (strong, nonatomic) IBOutlet UILabel *speedView;
@property(nonatomic) int speedCount;
@property (nonatomic,retain) CLLocationManager *locationManager;
@property (nonatomic, strong) WEPopoverController *popoverController;

+ (NSString *) speedToMPH: (float) value;


- (IBAction)btnMenuTapped:(id)sender;

@end