How to add PFObjects to a tableview in swift - ios

Question

I am building a checkin app, and am having trouble filling my tableview with guests stored using Parse. I get an error when trying to append the objects. I also have a user login that I followed from a Udemy course. In the course he showed how to display PFUsers, but I can't get it to work using PFObjects. Any help would be great on this.
Here is the working code with PFUsers.
var users = [""]
override func viewDidLoad() {
super.viewDidLoad()
var query = PFUser.query()
query!.findObjectsInBackgroundWithBlock({ (objects: [AnyObject]?, error: NSError?) -> Void in
self.users.removeAll(keepCapacity: true)
for object in objects! {
var user:PFUser = object as! PFUser
self.users.append(user.username!)
}
self.tableView.reloadData()
})
}
And here is the nonworking code with PFObjects.
var users = [""]
override func viewDidLoad() {
super.viewDidLoad()
var query = PFQuery(className: "TestObject")
query.findObjectsInBackgroundWithBlock({ (objects: [AnyObject]?, error: NSError?) -> Void in
self.users.removeAll(keepCapacity: true)
for object in objects! {
var guest = object as! PFObject
self.users.append(guest.foo!)
}
})
}
The error shows on the line
self.users.append(guest.foo!)
And the error says "'PFObject' does not have a member named 'foo'"

Answer 1

You define your PFUser object with the variable user, this will make the first example work (you get the name of the user) The second example doesn’t work cause you still define the PFObject as user but try to access the name of guest which is not defined.
You could either go with the first example or change
var user:PFObject = object as! PFObject
With
var guest:PFObject = object as! PFObject
Either way, it doesn’t matter for your code, it is just the name of the variable.
This explanation will fix your “Use of unresolved identifier ‘guest’”
But this isn’t your only problem,
the PFUser object which the first example uses is a special kind of a PFObject, the PFUser class does have a .name which refers to (obviously) the name of the user. Not every PFObject has a name though so you can’t just access the .name of a PFObject. Parse has an excellent documentation about retrieving objects I would first access this documentation. If this is still unclear to you, you can open another specific question about your new problem.
To retreive the data from an object you need to use []
Let’s suggest we have a class named gameScore with the following info
score: 1337, playerName: “Sean Plott”, cheatMode: false
We would do that as follows
var gameScore = PFObject(className:"GameScore")
gameScore["score"] = 1337
gameScore["playerName"] = "Sean Plott"
gameScore["cheatMode"] = false
gameScore.saveInBackgroundWithBlock {
(success: Bool, error: NSError?) -> Void in
if (success) {
// The object has been saved.
} else {
// There was a problem, check error.description
}
}
To retrieve the object you need to query (as you already did in your post)
Ones you’ve received the data you can extract it as follows:
let score = gameScore["score"] as Int
let playerName = gameScore[“playerName"] as String
let cheatMode = gameScore["cheatMode"] as Bool

Answer 2

I figured it out, I needed to get the object label as a string before I could append it to the array to then add it to the tableview.
Here is the working code:
var users = [""]
override func viewDidLoad() {
super.viewDidLoad()
var query = PFQuery(className: "TestObject")
query.findObjectsInBackgroundWithBlock({ (objects: [AnyObject]?, error: NSError?) -> Void in
self.users.removeAll(keepCapacity: true)
for object in objects! {
var foo = object.objectForKey("foo") as? String
self.users.append(foo!)
}
self.tableView.reloadData()
})
}