Can I integrate UIViewController and UICollectionViewController in one app?

Question

In an app I'm making, I'm trying to mix a UIViewContoller and a UICollectionViewController in two different view controllers. The CollectionViewController Cells won't show up in the app. I was wondering how I incorporate it in to my interface in the viewcontroller.h.

Current ViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface ViewController : UIViewController <UIImagePickerControllerDelegate, UINavigationControllerDelegate>
- (IBAction)cameraButtonClicked:(id)sender;
@property (strong, nonatomic) IBOutlet UIImageView *imageView;


@end

Answer 1

@interface ViewController : UIViewController <UIImagePickerControllerDelegate, UINavigationControllerDelegate, UICollectionViewDelegate, UICollectionViewDataSource>
- (IBAction)cameraButtonClicked:(id)sender;
@property (strong, nonatomic) IBOutlet UIImageView *imageView;
@property (strong, nonatomic) UICollectionView *collectionView
@end

Then, on your ViewController.m:

- (void)viewDidload{
    self.collectionView = ({
        UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc]init];
        flowLayout.itemSize = CGSizeMake(300, 107);
        flowLayout.minimumLineSpacing = 10.f;
        [[UICollectionView alloc]initWithFrame:self.view.frame collectionViewLayout:flowLayout];
    });

    [self.collectionView setAlwaysBounceVertical:YES];
    [self.collectionView setContentInset:UIEdgeInsetsMake(60, 0, 0, 0)];
    self.collectionView.backgroundColor = [UIColor whiteColor];
    [self.view addSubview:self.collectionView];

    self.collectionView.dataSource = self;
    self.collectionView.delegate = self;
    [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"Cell"];
}

Also, I think you're kind of confused on the term "View Controller" and "View." A UICollectionViewController is the object you drag onto your Storyboard from the Objects Library (on your Utilities panel). A UICollectionView is a subclass of UIScrollView (just like UITableView) that incorporates a series of methods that give it it's behavior.

Please note that, since you're conforming to the UICollectionViewDataSource and the UICollectionViewDelegate protocols, you should implement the @required methods from those protocols:

1. - (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView;
2. - (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section;
3. - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath;

Hope I helped.