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Joseph Lau
5,420 PointsWhat does this mean?
I was following a tutorial for this. I see this kind of stuff once in a while but what is the point of adding (UICollectionViewCell *) within this line of code?? I tried removing it and the app ran alright.
UICollectionViewCell *cell = (UICollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];
4 Answers
Thomas Nilsen
14,957 PointsHave a look at this first: http://www.tutorialspoint.com/objective_c/objective_c_type_casting.htm
Now, if you have a look at the method
- (id)dequeueReusableCellWithReuseIdentifier:(NSString *)identifier forIndexPath:(NSIndexPath*)indexPath
it returns an 'id', which means 'any kind of object'. But since you know what kind of object you're gonna be using you can write this:
UICollectionViewCell *cell = (UICollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];
Joseph Lau
5,420 PointsStill don't really get it. What does...
[collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath]
...return anyway?
Thomas Nilsen
14,957 Pointsyou collectionView object calls the method:
- (id)dequeueReusableCellWithReuseIdentifier:(NSString *)identifier forIndexPath:(NSIndexPath*)indexPath
Which, like I said previously, returns 'id', which is a generic object.
Joseph Lau
5,420 Pointshow come it works even without
(UICollectionViewCell *)
in the expression? what for?