How to rotate CollectionView Cell so item stays centered? - ipad

Question

I have a UIcollectionView in an iPad app set up to display one photo at a time. When I rotate the from an image in Landscape I'd like to have the image resize so that the image shown when the rotation starts is centered when the rotation ends in Portrait. The resizing works, but the border between two items is shown when the rotation ends. I have no idea how keep the image centered as I would like.
Maybe "centered" is the wrong way to put it, maybe I mean keeping the left side of the image at the left side of the frame. Being new to iOS and Swift, part of my problem is I don't know enough to even frame (no pun intended) the issue properly.
This image shows the problem and what I am trying to accomplish.
Is it possible to do what I want to do and, if so, what's the best way?
Here is the code so far:
class PhotoCollectionViewController: UICollectionViewController {
var businessData = [BData]()
var theBusiness:BData?
var currentDevice: UIDevice = UIDevice.currentDevice()
override func viewDidLoad() {
super.viewDidLoad()
definesPresentationContext = true
businessData = appData.getBusinessData()
}
override func numberOfSectionsInCollectionView(collectionView:
UICollectionView) -> Int {
return 1
}
override func collectionView(collectionView: UICollectionView,numberOfItemsInSection section: Int) -> Int {
return businessData.count
}
override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell{
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("photoCell", forIndexPath: indexPath) as! PhotoCell
// Configure the cell
let dirPaths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let docsDir = dirPaths[0]
let theBusinessPhoto = docsDir+"/bPhotos/"+businessData[indexPath.row].bPhotoFilename!
cell.splashPhoto.image = UIImage(contentsOfFile: theBusinessPhoto)
return cell
}
override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
if let cell = collectionView.cellForItemAtIndexPath(indexPath) {
performSegueWithIdentifier("gotoBusinessInfo", sender: cell)
} else {
// Error.
}
}
override func viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) {
showViewSettings()
self.collectionView!.collectionViewLayout.invalidateLayout()
view.layoutIfNeeded()
}
func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
if (currentDevice.orientation.isLandscape){
return CGSizeMake(1024, 704)
} else {
return CGSizeMake(768, 528)
}
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
assert(sender as? UICollectionViewCell != nil, "sender is not a collection view")
if let indexPath = self.collectionView?.indexPathForCell(sender as! UICollectionViewCell) {
if segue.identifier == "gotoBusinessInfo" {
let businessDetailVC = segue.destinationViewController as! BusinessInfoVC
businessDetailVC.businessData = businessData[indexPath.row]
}
} else {
// Error.
}
}
func showViewSettings(){
print ("Device......: " + UIDevice.currentDevice().name)
print ("Model.......: " + UIDevice.currentDevice().localizedModel)
print ("Orientation.: " + String(UIDevice.currentDevice().orientation.rawValue))
print ("View width..: " + String(self.view.bounds.size.width))
print ("View height.: " + String(self.view.bounds.size.height))
print ("S.bar height: " + String(UIApplication.sharedApplication().statusBarFrame.height))
print ("S.bar hidden: " + String(UIApplication.sharedApplication().statusBarHidden))
print ("N.bar height: " + String(self.navigationController?.navigationBar.frame.height))
}
}
showViewSettings() is just a debug aid.