Swift: UIRefreshControl does not pull through when dragging down - swift

Question

I have a working UITableView in which I added a UIRefreshControl like this:
var refresher: UIRefreshControl!
...
// this is ViewDidLoad()
// pull to refresh
refresher = UIRefreshControl()
refresher.tintColor = globalClass.blue
refresher.attributedTitle = NSAttributedString(string: "")
refresher.addTarget(self, action: "loadFriends", forControlEvents: UIControlEvents.ValueChanged)
friendTableView.addSubview(refresher)
This works well on other UITableViews, but not on this one for some reason. The spinner never really spins and just snaps to the top when the dragging stops. What could cause this?
EDIT: loadFriends function
//load friends
func loadFriends() {
globalClass.requestsIn = []
globalClass.requestsOut = []
globalClass.finalSections = []
globalClass.myFriends = []
finalSections = []
sectionsG1 = []
let queryIn1 = PFQuery(className:"Friendship")
queryIn1.whereKey("toUser", equalTo: PFUser.currentUser()!.username!)
let queryOut = PFQuery(className:"Friendship")
queryOut.whereKey("fromUser", equalTo: PFUser.currentUser()!.username!)
let query = PFQuery.orQueryWithSubqueries([queryIn1, queryOut])
query.orderByDescending("createdAt")
query.findObjectsInBackgroundWithBlock {
(objects: [AnyObject]?, error: NSError?) -> Void in
if error == nil {
if objects!.count == 0 {
self.friendtTableView.reloadData()
self.text()
} else {
for object in objects! {
let toUser:String = object["toUser"] as! String
let status:String = object["status"] as! String
if toUser == PFUser.currentUser()?.username {
if status == "pending" {
globalClass.requestsIn.append(object["fromUser"] as! String)
self.update()
} else if status == "approved" {
globalClass.myFriends.append(object["fromUser"] as! String)
globalClass.myFriends = globalClass.myFriends.sorted { $0.localizedCaseInsensitiveCompare($1) == NSComparisonResult.OrderedAscending }
self.update()
}
} else { if status == "pending" || status == "rejected" {
globalClass.requestsOut.append(object["toUser"] as! String)
self.update()
} else if status == "approved" {
globalClass.myFriends.append(object["toUser"] as! String)
globalClass.myFriends = globalClass.myFriends.sorted { $0.localizedCaseInsensitiveCompare($1) == NSComparisonResult.OrderedAscending }
self.update()
}
}
}
}
if self.tableSegment == 1 {
if globalClass.requestsIn.count == 0 {
self.friendTableView.reloadData()
self.text()
} else {
}
} else if self.tableSegment == 2 {
if globalClass.requestsOut.count == 0 {
self.friendTableView.reloadData()
self.text()
} else {
}
} else if self.tableSegment == 0 {
if globalClass.myFriends.count == 0 {
self.friendTableView.reloadData()
self.text()
} else {
}
}
self.refresher.endRefreshing()
} else {
}
}
}