iOS

check space

func deviceRemainingFreeSpaceInBytes() -> Int64? {
  let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
  let systemAttributes = NSFileManager.defaultManager().attributesOfFileSystemForPath(documentDirectoryPath.last as String, error: nil)
  let freeSize = (systemAttributes?[NSFileSystemFreeSize] as? NSNumber)?.longLongValue
  return freeSize
}

if let bytes = deviceRemainingFreeSpaceInBytes() {
  println("free space: \(bytes)")
} else {
  println("failed")
}

displayAlert

func displayErrorAlert (title :String, error :String) {
  var alert = UIAlertController(title: title, message: error, preferredStyle: UIAlertControllerStyle.Alert)
  alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { (action) -> Void in
    self.dismissViewControllerAnimated(true, completion: nil)
  }))
  self.presentViewController(alert, animated: true, completion: nil)
}

loadSpinner

var activityIndicator = UIActivityIndicatorView()

func loadSpinner() {
  activityIndicator = UIActivityIndicatorView(frame: CGRectMake(0, 0, 50, 50))
  activityIndicator.center = self.view.center
  activityIndicator.hidesWhenStopped = true
  activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.Gray
  view.addSubview(activityIndicator)
  activityIndicator.startAnimating()
  UIApplication.sharedApplication().beginIgnoringInteractionEvents()
}

pullToRefresh

var refresher: UIRefreshControl!
refresher = UIRefreshControl()
refresher.attributedTitle = NSAttributedString(string: "Pull to refresh")
refresher.addTarget(self, action: "refresh", forControlEvents: UIControlEvents.ValueChanged)
self.tableView.addSubview(refresher)

func refresh() {
  // code to execute during refresh
  refresher.endRefreshing()
}

unloadSpinner

var activityIndicator = UIActivityIndicatorView()

func unloadSpinner() {
  activityIndicator.stopAnimating()
  UIApplication.sharedApplication().endIgnoringInteractionEvents()
}