UICollectionView reloadData doesn't work correctly - ios

Question

I'm face a strange problem, when I execute from an action (button) the reloadData of my UICollectionView the cells are not displayed correctly, only the background image of the cells are ok.
My "INVPropertyCell" is composed with a background image and 2 labels (title & price). When I execute the reloadData the above labels from cells disappeared randomly.
I have done a lot of searches in the different forums, some people have the same problem but I didn't find out a fix.
Below, you will find my code, if someone can help me it would be very very appreciated.
Jérôme.
- (void)viewDidLoad
{
NSLog (#"INVPropertiesViewController -- viewDidLoad");
[super viewDidLoad];
// Enregistrement de la cellule.
[self.clProperties registerNib:[UINib nibWithNibName:#"INVPropertyCell" bundle:nil] forCellWithReuseIdentifier:#"propertyCell"];
// Enregistrement du header de section
[self.clProperties registerNib:[UINib nibWithNibName:#"INVPropertyHeaderSection" bundle:nil] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:#"headerCollectionCell" ];
self.clProperties.delegate = self;
self.clProperties.dataSource =self;
NSLog (#"INVPropertiesViewController -- End of viewDidLoad");
}
- (void)viewWillAppear:(BOOL)animated
{
NSLog (#"INVPropertiesViewController -- viewWillAppear");
[super viewWillAppear:animated];
categoryDictionary = [ServiceDatas getCategoriesDictionary];
tblProperties = [(NSArray*)[ServiceDatas getListPropertiesByLieuFromLocalDataStore:self.selectedResidence] mutableCopy];
if(tblProperties.count==0 & self.selectedResidence.propertiesCount.longValue >0)
tblProperties = [(NSArray*)[ServiceDatas getListPropertiesByLieuFromServer:self.selectedResidence] mutableCopy];
tblPropertiesByCategory = [ServiceDatas createCategoryBreakDown:tblProperties];
keysCategories = [tblPropertiesByCategory allKeys];
[self.clProperties reloadData];
NSLog (#"INVPropertiesViewController -- End of viewWillAppear");
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{
// [self.clProperties.collectionViewLayout invalidateLayout];
return tblPropertiesByCategory.count;
}
- (UICollectionReusableView *)collectionView: (UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath{
UICollectionReusableView *reusableview = nil;
if(kind == UICollectionElementKindSectionHeader){
INVPropertyHeaderSection *headerSection = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:#"headerCollectionCell" forIndexPath:indexPath];
id categoryId = [keysCategories objectAtIndex:indexPath.section];
CategoryModel *category = categoryDictionary[categoryId];
if(category!=nil){
headerSection.backgroundColor = [Utils colorFromHexString:category.color];
headerSection.lblCategory.text = [category.title uppercaseString];
}
reusableview = headerSection;
}else if(kind == UICollectionElementKindSectionFooter){
if (reusableview==nil) {
reusableview=[[UICollectionReusableView alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];
}
}
return reusableview;
}
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
// Return the number of rows in the section.
id categoryId = [keysCategories objectAtIndex:section];
NSMutableArray *tblProperties = [tblPropertiesByCategory objectForKey:categoryId];
return [tblProperties count];
}
// The cell that is returned must be retrieved from a call to -dequeueReusableCellWithReuseIdentifier:forIndexPath:
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
INVPropertyCell *cell = nil;
id categoryId = [keysCategories objectAtIndex:indexPath.section];
NSMutableArray *tblProperties = [tblPropertiesByCategory objectForKey:categoryId];
if(tblProperties!=nil){
cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"propertyCell" forIndexPath:indexPath];
PropertyModel *property = [tblProperties objectAtIndex:indexPath.item];
NSLog(#"Ligne %ld - Colonne %ld - Lieux %#",indexPath.section, (long)indexPath.item, property.title );
CategoryModel *category = categoryDictionary[categoryId];
if(category!=nil){
[cell initWithProperty:property backgroundColor:[Utils colorFromHexString:category.color]];
}
}
return cell;
}
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
// Récupération du bien courant.
id categoryId = [keysCategories objectAtIndex:indexPath.section];
NSMutableArray *tblProperties = [tblPropertiesByCategory objectForKey:categoryId];
PropertyModel *property = [tblProperties objectAtIndex:indexPath.row];
NSLog(#"Property sélectionnée : %#",property.title);
self.selectedProperty = property;
if(property!=nil && [property.title isEqualToString:EMPTY_PROPERTY]){
self.selectedProperty = nil;
}
// Déclenche le Segue pour aller à l'écran "Property"
[self performSegueWithIdentifier:#"segueEditPropertyView" sender:self];
}
// Layout: Set cell size
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
CGSize mElementSize = CGSizeMake(107, 106);
if(indexPath.item==0){
mElementSize = CGSizeMake(106, 106);
}
return mElementSize;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 0.0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
return 0.0;
}
// Layout: Set Edges
- (UIEdgeInsets)collectionView:
(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(0,0,0,0); // top, left, bottom, right
}
- (IBAction)btnRefresh:(id)sender {
[self.clProperties reloadData];
}

Answer 1

i think,you have to register class before register nib for both INVPropertyCell and INVPropertyHeaderSection cell.

Answer 2

You try check and alloc cell if it is null in collectionView..cellForItemAtIndexPath
cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"propertyCell" forIndexPath:indexPath];
if (cell == null) {
Array *xibs = [[NSBundle mainBundle] loadNibWithNamed:#"propertycell"
...];
cell = xibs[0];
}
I'm coding in swift, so maybe above syntax is wrong, but this is idea :)