UICollectionViewCell subclass init never run - ios

Question

I have added a collection view in viewDidLoad like this...
self.collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, 10, 10) collectionViewLayout:flowLayout];
self.collectionView.delegate = self;
self.collectionView.dataSource = self;
self.collectionView.backgroundColor = [UIColor whiteColor];
[self.collectionView registerClass:[CameraCell class] forCellWithReuseIdentifier:CameraCellReuseIdentifier];
[self.collectionView setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.view addSubview:self.collectionView];
And I have a UICollectionViewCell subclass called CameraCell with an init like this...
- (id)init
{
self = [super init];
if (self) {
// Add customisation here...
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(imageChanged:) name:#"image" object:nil];
self.contentView.backgroundColor = [UIColor yellowColor];
self.imageView = [[UIImageView alloc] initWithFrame:CGRectZero];
self.imageView.contentMode = UIViewContentModeScaleAspectFill;
self.imageView.clipsToBounds = YES;
[self.imageView setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.contentView addSubview:self.imageView];
NSDictionary *views = NSDictionaryOfVariableBindings(_imageView);
[self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"V:|[_imageView]|"
options:0
metrics:nil
views:views]];
[self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"|[_imageView]|"
options:0
metrics:nil
views:views]];
}
return self;
}
But when I run the app the collection view is there and I can scroll it but I can't see any cells. I have added a breakpoint in the cell's init and it never gets called. Is there another method I have to override?
EDIT
When I log the cell in cellForItemAtIndexPath...
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CameraCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:CameraCellReuseIdentifier forIndexPath:indexPath];
NSLog(#"%#", cell);
return cell;
}
It displays the correct class...
<CameraCell: 0x1f07ba30; baseClass = UICollectionViewCell; frame = (0 20; 320 280); layer = <CALayer: 0x1f07bb40>>

Answer 1

The method you need to implement is - (instancetype)initWithFrame:(CGRect)rect

Answer 2

I recently tried this in the iOS7 SDK, and I had to override initWithCoder because initWithFrame was never called.

Answer 3

If the cell is loaded from a StoryBoard then you will want to override the initializers like this:
Swift
override init?(coder aDecoder: NSCoder) {
super.init(coder:aDecoder)
//You Code here
}
Objective-C
- (id)initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
//You code here
}
If you are loading from a nib, then you will want to override the initializers like this:
Swift
override init(frame: CGRect) {
super.init(frame:frame)
//You Code here
}
Objective-C
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
//You code here
}

Answer 4

I know the question is way old, but personally I was lazy and wanted to copy-paste code from somewhere. Unfortunately, there is no 100% correct solution above so I wrote common pattern (for both IB-based and code-based cells)
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
override func awakeFromNib() {
commonInit()
}
private func commonInit() {
}

Answer 5

In my case, when I am using [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, 10, 10) collectionViewLayout:flowLayout] to programatically instantiate a collectionView, initWithFrame never get called, but initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout did.

Answer 6

Swift 5:
required init?(coder aDecoder: NSCoder) {
super.init(coder:aDecoder)
// Your code here.
}