Unrecognized selector on custom subclass - ios

Question

I spent some time looking around other similar posts but was unable to find my exact problem. I'm new to iOS and objective c so it's probably very simple.
I'm subclassing UICollectionViewCell:
#interface FooCollectionViewCell : UICollectionViewCell
#property (weak, nonatomic) IBOutlet UILabel *cellLabel;
#end
And in my custom subclass of UIViewController, i'm trying to set a value for cellLabel:
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
FooCollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:reuseIdentifier forIndexPath:indexPath];
// Configure the cell
UILabel *label = [[UILabel alloc] init];
label.text = #"whatever";
cell.cellLabel = label;
return cell;
}
My app crashes when run:
[UICollectionViewCell setCellLabel:]: unrecognized selector sent to instance 0x7fef224144f0
If I'm understanding that error, it looks it's complaining that i'm trying to set the cellLabel property on an instance of UICollectionViewCell the superclass instead of an instance of FooCollectionViewCell the subclass.
However, when I add a breakpoint at that line and look at my variables, I see:
cell FooCollectionViewCell * 0x7fcb5340dcd0 0x00007fcb5340dcd0
It also seems obvious from my code that the object has to be of type FooCollectionViewCell because that's the type cell is instantiated as.
My process for setting up my storyboard was:
Drag a CollectionViewController to my storyboard
Set its Custom Class to FooCollectionViewController. This seems to work because my code is called.
Click the prototype cell automatically created within the automatically created Collection View, set its Custom Class to FooCollectionViewCell. Set the Identifier to "FooCell", and update the reuseIdentifier variable in my ViewController to also be "FooCell".
Is there something I'm missing?

Answer 1

you say that you follow tutorial. So have you done these steps?
With the basic collection view classes implemented and associated with the storyboard objects, it is now time to design the cell. This is, quite simply, a matter of dragging and dropping items from the object library onto the prototype cell in the storyboard view. Additionally the size of the cell may be modified by selecting it and using the resulting resize handles. The exact design of the cell is entirely dependent on what is to be displayed. For the purposes of this example, however, each cell is simply going to display an image.
Because you are creating a new label in the code, when it should be already available in prototype cell. You only have to assign cell.cellLabel.text = #"bla bla";
UILabel *label = [[UILabel alloc] init];
label.text = #"whatever";
cell.cellLabel = label;

Answer 2

I figured out the problem. When I created my view controller subclass the file automatically had
[self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];
in my viewDidLoad method. So I think that was overriding what I was doing in my storyboard. FML but I learned something. Thanks for the help!
The fix was to remove this line since I'm configuring that in my storyboard.