How To Set up a UIPageViewController - ios

Question

I have been looking for tutorials regarding the setup of a UIPageViewController because somebody recommended not using my navigational controller but instead to use the PageView. I am using the swipe gesture left and right as well but I am yet to find a good tutorial online in regards to the setup of the UIPageViewController via storyboard (or at least majority storyboard).
I included a picture of what I am working with at the moment: http://imgur.com/a0iuFNW
Any help in regards to the setup of the PageViewController and then following controllers would be much appreciated!
Thank you for your help in advanced

Answer 1

I'm sure you can find some tutorials out there if you Google it, but this should give you a start trying your own implementation. I created a new project starting from the "Page-Base Application" template. You should study the code that gives you to try to understand what it does (along with reading Apple's documentation on UIPageViewController).
That project creates several objects. The RootViewController creates the page view controller and adds it as a child view controller. For my test app, I didn't change anything in this file other than changing the transition style of the page view controller to UIPageViewControllerTransitionStyleScroll (instead of page curl, but you should try the original value too to see what it looks like).
The ModelController class contains the model, which in your case would be an array of image names (or pieces of the name as I have). This class implements the page view controller data source methods that handle the turning of the pages. I changed the init method in that class to this,
- (id)init {
if (self = [super init]) {
_pageData = #[#"1", #"2", #"3", #"4", #"5", #"6"]; // my images are named img1.JPG, img2.JPG, etc. I will use these numbers to construct the path to my files in the bundle
}
return self;
}
So, you can see that the model is just an array of number strings (one number for each image). You might have to try something different depending on how your images are named. When you swipe between pages, the index into this array is either incremented or decremented, and the value in the array is passed to the DataViewController into its dataObject property.
The DataViewController is the controller that actually shows your content. It's the right controller in the storyboard. I modified its view by adding a navigation bar at the top so we can put in a title and button (to go to your tips view controllers), and replaced the UIView subview with a UIImageView that takes up the whole screen under the navigation bar. I made IBOutlets to the image view and the navigation bar. Here is the changed .h file for that controller,
#interface DataViewController : UIViewController
#property (strong, nonatomic) NSString *dataObject;
Finally, in the .m file, I made it look like this,
#interface DataViewController ()
#property (weak,nonatomic) IBOutlet UINavigationBar *bar;
#property (weak,nonatomic) IBOutlet UIImageView *iv;
#end
#implementation DataViewController
- (void)viewDidLoad{
[super viewDidLoad];
UINavigationItem *titleItem = self.bar.items[0];
titleItem.title = [NSString stringWithFormat:#"Course Guide %#",self.dataObject];
NSString *imagePath = [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:#"img%#", self.dataObject] ofType:#"JPG"];
self.iv.image = [UIImage imageWithContentsOfFile:imagePath];
}
-(void)dealloc {
NSLog(#"in dealloc");
}
I'm using initWithContentsOfFile: to create the images (rather than imageNamed: because it doesn't cache the images) based on the number that's passed in to the dataObject. I implemented dealloc to illustrate the fact that as you swipe back and forth through the pages, the controllers are deallocated, thus keeping your memory footprint small. If the transition style is page curl, the controllers are deallocated as soon as they go off screen, so there's never more than one in existence at a time. If the style is scroll, then there are 3 in existence at a time, because the page view controller creates the current one as well as the previous and next ones to make the loading faster.
As you can see, I've made only a few small changes to the code the template gives you, in order to display an array of images which should suit your purpose. A structure such as this for your app will be much more memory efficient than using a stack of controllers in a navigation controller.