uicollectionview cell frame in portrait and landscape - ios

Question

I am stuck in frame of uicollectionview cell frame
what I want to do is,
in landscape mode of iPad I want to show 3 cells,
and in portrait 2 cells.
when I write the code of frame in method - (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
its not affecting the size of frame.
I checked by applying debugger whether its coming in this method or not.
but its coming and returning the size.
by default I have to launch my application in landscape and then if required in portrait.
Here is how its showing in landscape
Here how this cells looking in portrait
Here is my code for frame
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
//return [self.cellSizes[indexPath.item] CGSizeValue];
if (UIDeviceOrientationIsLandscape([[UIApplication sharedApplication] statusBarOrientation]))
{
return CGSizeMake(100, 100);
}
return CGSizeMake(200, 200);
}
What ever value I pass, frame is not at all changing.
I didn't passed any other frame value any where.
I want to give hardcoded value to cell frame first then will go for dynamic.
but I'm stuck at the first place only.
Can any one please help me.
Thanks in advance.

Answer 1

i faced similiar problem so basically you should implement UICollectionViewDelegateFlowLayout in your view controller otherwise design a custom collectionviewcell and register in your view controller , it will definitely work . Try it .
in my case
i added xib by subclassing UICollectionViewCell and designed it accordingly and it works so you may try .

Answer 2

For dynamic collection view cell you can use collection view methods like this.
-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{
return 1;
}
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection: (NSInteger)section{
return [_elements count];
}
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
static NSString *cellIdentifier = #"cell";
MosaicCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];
MosaicData *data = [_elements objectAtIndex:indexPath.row];
cell.mosaicData = data;
float randomWhite = (arc4random() % 40 + 10) / 255.0;
cell.backgroundColor = [UIColor colorWithWhite:randomWhite alpha:1];
return cell;
}
For details you can see this example. This is an perfect example of your need
https://github.com/betzerra/MosaicLayout

Answer 3

You need to reload the collection view when orientation will get change. so the CGRect size method will be called for the cell to recreate cell.
- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
// do something after rotation
[_collectView reloadData];
}
Add this method and reload your collection view so - (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath will get called and size will get changed.
Thanks