Can't access array values outside of function - Swift - swift

Question

I'm trying to query my Parse database in order to search for a username and show all posts related to the username. The posts are split into two fields and I "paste" them back together inside the function.
func searchDataBase() -> ([String]) {
if let username = PFUser.currentUser()?.username {
userHeading.text = username + "'s Profile"
var query = PFQuery(className:"Wish")
query.whereKey("user", equalTo:username)
query.findObjectsInBackgroundWithBlock {
(objects: [AnyObject]?, error: NSError?) -> Void in
if error == nil {
// The find succeeded.
println("Successfully retrieved \(objects!.count) wishes.")
// Do something with the found objects
if let objects = objects as? [PFObject] {
for object in objects {
//println(object.objectId)
var parseID = object.objectId!
var query = PFQuery(className:"Wish")
query.getObjectInBackgroundWithId(parseID) {
(detailedWish: PFObject?, error: NSError?) -> Void in
if error == nil {
let partOne = detailedWish!["wishFieldOne"] as! String
let partTwo = detailedWish!["wishFieldTwo"] as! String
let fullWish = "I wish I " + partOne + " when I " + partTwo
self.wishes.append(fullWish)
} else {
println(error)
}
}
}
}
} else {
// Log details of the failure
println("Error: \(error!) \(error!.userInfo!)")
}
}
} else {
println("No user logged in")
}
return wishes
}
After the function above runs, I want to place the user's posts inside a UITableView:
//TABLE VIEW FUNCTIONS
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
searchDataBase()
return wishes.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = recentPosts.dequeueReusableCellWithIdentifier(textCellIdentifier, forIndexPath: indexPath) as! UITableViewCell
searchDataBase()
let row = indexPath.row
cell.textLabel?.text = wishes[row]
return cell
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
recentPosts.deselectRowAtIndexPath(indexPath, animated: true)
searchDataBase()
let row = indexPath.row
println(wishes[row])
}
When I build the app the UITableView doesn't show the posts I queried in the searchDataBase function. If I println(wishes) immediately after the array is appended, it works, but when I print the array outside of the function it is empty. How can I make the contents of the wishes array accessible outside the function - after the query is successful?
Thanks for your help!

Answer 1

This is an odd approach. Your calling searchDataBase() on every tableView method. You surely dont want to make a call to parse every time? Also your searchDataBase() method doesnt need to return an array. You can simply just append the results to this array and reload your table when complete. Im assuming this would be a much better approach for you.
So, my solution to you would be to remove your searchDatabase() function call from all your tableView methods and to place it inside your viewDidLoad(). Also you should change you searchDataBase() to look like so
func searchDataBase(){
if let username = PFUser.currentUser()?.username {
userHeading.text = username + "'s Profile"
var query = PFQuery(className:"Wish")
query.whereKey("user", equalTo:username)
query.findObjectsInBackgroundWithBlock {
(objects: [AnyObject]?, error: NSError?) -> Void in
if error == nil {
// The find succeeded.
println("Successfully retrieved \(objects!.count) wishes.")
// Do something with the found objects
if let objects = objects as? [PFObject] {
for object in objects {
//println(object.objectId)
var parseID = object.objectId!
var query = PFQuery(className:"Wish")
query.getObjectInBackgroundWithId(parseID) {
(detailedWish: PFObject?, error: NSError?) -> Void in
if error == nil {
let partOne = detailedWish!["wishFieldOne"] as! String
let partTwo = detailedWish!["wishFieldTwo"] as! String
let fullWish = "I wish I " + partOne + " when I " + partTwo
self.wishes.append(fullWish)
} else {
println(error)
}
}
}
}
self.tableView.reloadData() // <- This will populate your tableView with your wishes
} else {
// Log details of the failure
println("Error: \(error!) \(error!.userInfo!)")
}
}
} else {
println("No user logged in")
}
}

Answer 2

You can't do what you are trying to do that way.
What you need to do is to rewrite your searchDataBase method to take a completion closure as a parameter. Then in the completion block to your call to query.getObjectInBackgroundWithId, build your result array and pass to the searchDataBase completion closure.

Answer 3

searchDataBase() performs the returns the array. Where's the variable wishes that you're accessing?
Instead:
let wishes = searchDataBase()
and then you'll have the array for your table view delegate functions.