Delegate does not get called - objective-c

Question

I have a UIPageViewController which I setup in the viewDidLoad method of the RootViewController as follows:
[self addChildViewController:self.pageViewController];
[self.view addSubview:self.pageViewController.view];
The delegate pageViewControllerspineLocationForInterfaceOrientation is called successfully and I can set the spine accordingly.
However, I want to setup the PageViewController on a button click so I moved the code to the event handler of the button pressed event. Now the delegate is not called.
Any ideas how I can fix it?

Answer 1

It is some what complicated but can be achieved through the code below :
Step 1: Add below code to .h file of rootViewController.
#property (strong, nonatomic) IBOutlet UIButton *previousClick;
#property (strong, nonatomic) IBOutlet UIButton *nextClick;
Step 2: Connect them to the xib or storyboard which ever you use.
Step 3: Add two IBAction methods to .m file.
#pragma mark - IBAction Methods
- (IBAction)previousClick:(id)sender
{
[_modelController pageViewController:self.pageViewController viewControllerBeforeViewController:_dataViewController];
}
- (IBAction)nextClick:(id)sender
{
[_modelController pageViewController:self.pageViewController viewControllerAfterViewController:_dataViewController];
}
Step 4: You also need to put below lines too to .m file
#interface RootViewController ()
#property (readonly, strong, nonatomic) ModelController *modelController;
#property (readonly, strong, nonatomic) DataViewController *dataViewController;
#end
And synthesize them as below
#synthesize modelController = _modelController;
#synthesize dataViewController = _dataViewController;
Step 5: Last and final add below line to - (UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation method.
_dataViewController = currentViewController;
after the currentViewController's alloc init call.
If you find that the added buttons are hidden by the pageViewController just bring them to the front using the code below in side the -viewDidLoad method
[self.view bringSubviewToFront:self.previousClick];
[self.view bringSubviewToFront:self.nextClick];