UICollectionView reloadData not functioning properly in iOS 7

Question

I\'ve been updating my apps to run on iOS 7 which is going smoothly for the most part. I have noticed in more than one app that the reloadData method of a

Answer 1

You can use this method

[collectionView reloadItemsAtIndexPaths:arayOfAllIndexPaths];

You can add all indexPath objects of your UICollectionView into array arrayOfAllIndexPaths by iterating the loop for all sections and rows with use of below method

[aray addObject:[NSIndexPath indexPathForItem:j inSection:i]];

I hope you understood and it can resolve your problem. If you need any more explanation please reply.

Answer 2

Reloading some items didn't work for me. In my case, and only because the collectionView I'm using has just one section, I simply reload that particular section. This time the contents are correctly reloaded. Weird that this is only happening on iOS 7 (7.0.3)

[self.collectionView reloadSections:[NSIndexSet indexSetWithIndex:0]];

Answer 3

Swift 5 – 4 – 3

// GCD    
DispatchQueue.main.async(execute: collectionView.reloadData)

// Operation
OperationQueue.main.addOperation(collectionView.reloadData)

Swift 2

// Operation
NSOperationQueue.mainQueue().addOperationWithBlock(collectionView.reloadData)

Answer 4

Force this on the main thread:

dispatch_async(dispatch_get_main_queue(), ^ {
    [self.collectionView reloadData];
});

Answer 5

It happened with me too in iOS 8.1 sdk, but I got it correct when I noticed that even after updating the datasource the method numberOfItemsInSection: was not returning the new count of items. I updated the count and got it working.

Answer 6

Here is how it worked for me in Swift 4

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

let cell = campaignsCollection.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! Cell

cell.updateCell()

    // TO UPDATE CELLVIEWS ACCORDINGLY WHEN DATA CHANGES
    DispatchQueue.main.async {
        self.campaignsCollection.reloadData()
    }

    return cell
}