UICollectionView reload error

Question

I have a problem reloading data using a UICollectionView . I have this array on viewDidLoad to populate a UICollectionView.

 array = [[NSMutableArray alloc] init]; [array addObject:@"1"]; [array addObject:@"2"]; [array addObject:@"3"]; [array addObject:@"4"]; [array addObject:@"5"]; [array addObject:@"6"]; 

and method:

 -(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath { NSString *cellIdentifier = @"Cell"; //cell = [[UICollectionViewCell alloc] initWithFrame:CGRectMake(0, 0, 100, 100)]; myCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath]; UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(5, 0, 100, 20)]; [titleLabel setText:[array objectAtIndex:indexPath.row]]; titleLabel.textColor = [UIColor whiteColor]; titleLabel.backgroundColor = [UIColor clearColor]; [cell addSubview:titleLabel]; return cell; } 

I UIButton and the data is reloaded:

 [myCollectionView reloadData]; 

Here's what the data looks like before and after the reboot:

Answer 1

Each time you press the reload button, you add a new label. You must add the label once and change the label text to match.

Here is a simple example.

 - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath { MyCell *cell = (MyCell *)[collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath]; [cell setMyTextLabel:indexPath.row]; return cell; } 

where MyCell will contain the UILabel and the property to change its text.

I really suggest taking a look at Fun with the UICollectionView code from @Ben Scheirman .

Hope this helps.

PS Rename MyCell to MyCell . The class must begin with an uppercase letter.

Answer 2

You add your shortcut when you press the reset button. In this case, you add the shortcut again and again ...

So there are three solutions:

• Make your cell reusable
• Remove your cell from the supervisor in reboot mode.
• You can check if the length of the text label is not equal to zero. In this case, there is no need to add this label and change the text.

Answer 3

  - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath { UICollectionViewCell *cell=[collectionView dequeueReusableCellWithReuseIdentifier:@"cellIdentifier" forIndexPath:indexPath]; dispatch_async(dispatch_get_main_queue(), ^{ // ********* Changed ******* for (UIView *v in [cell.contentView subviews]) [v removeFromSuperview]; // ********** Changed ********** if ([self.collectionviewFlow.indexPathsForVisibleItems containsObject:indexPath]) { NSString *img_name=[NSString stringWithFormat:@"%@_thumb%d.png",self.VaritiesName,(int)indexPath.row+1]; imageVw=[[UIImageView alloc]initWithImage:[UIImage imageNamed: img_name]]; imageVw.frame=CGRectMake(10,10,100,100); [cell.contentView addSubview:imageVw]; } }); cell.backgroundColor=[UIColor clearColor]; return cell; } 

Answer 4

It is already late, but here is my solution.

if you used the custom viewviewcell collection try using the func function prepareForReuse () '