Im just learning following beginner tutorial book , i have this code :
- (void) presentImagePickerUsingCamera:(BOOL)useCamera
{
    UIImagePickerController *cameraUI = [UIImagePickerController new];
    cameraUI.sourceType = (useCamera? UIImagePickerControllerSourceTypeCamera:
                                      UIImagePickerControllerSourceTypePhotoLibrary);
    cameraUI.mediaTypes = @[(NSString*)kUTTypeImage];
    cameraUI.delegate = self;
    [[self presentingViewController] dismissViewControllerAnimated:YES completion:nil]; 
    [self presentingViewController:cameraUI];
}
and this is the interface :
#import <UIKit/UIKit.h>
#import "MyWhatsit.h"
    @interface MSDetailViewController : UIViewController <UISplitViewControllerDelegate,
                                                           UIActionSheetDelegate,
                                                           UIImagePickerControllerDelegate,
                                                           UINavigationControllerDelegate>
    @property (strong,nonatomic) MyWhatsit* detailItem;
    @property (weak,nonatomic) IBOutlet UITextField *nameField;
    @property (weak,nonatomic) IBOutlet UITextField *locationField;
    @property (weak,nonatomic) IBOutlet UIImageView *imageView;
    - (IBAction)changeDetail:(id)sender;
    - (IBAction)chooseImage:(id)sender;
    - (void) presentImagePickerUsingCamera:(BOOL)useCamera;
    @end
gives me the error:
code/MSDetailViewController.m:89:11: No visible @interface for 'MSDetailViewController' declares the selector 'presentingViewController:'
i did try to find answers like here
but nothing help , what I'm doing wrong here ?