Display strings from an array in a column on screen in Swift?

Question

I have a ScrollView on my page and I have an array with a bunch of strings in it. I'm trying to display the strings on the page in a column with one string on each line.

---

For example I run:

let usernameData = documents.map { $0["playername"]! }

print(usernameData)

My Output shows:

[UsernameOne, UsernameTwo, UsernameThree, UsernameFour, UsernameFive]

---

And when I run:

let usernameData = documents.map { $0["playername"]! }

for usernames in usernameData {
   print(usernames)
}

My Output shows:

UsernameOne
UsernameTwo
UsernameThree
UsernameFour
UsernameFive

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When I try to add these strings to show on my ScrollView in a column I was trying to just add them to a SKLabelNode and assign my string as text, then I would just increment the y position of the SKLabelNode for each string. For example:

I ran this:

let stringOne = SKLabelNode(fontNamed: "Times New Roman")
let usernameData = documents.map { $0["playername"]! }

for usernames in usernameData {
   self.stringOne.text = usernames as? String
   self.stringOne.fontSize = 150
   self.stringOne.fontColor = SKColor.white
   self.stringOne.position = CGPoint(x: self.frame.midX * 1.50, y: self.contrainer.frame.maxY * 2.90)
   self.stringOne.zPosition = 100
   self.moveableNode.addChild(self.stringOne)

}

But it failed because:

 Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Attemped to add a SKNode which already has a parent: <SKLabelNode> name:'(null)' text:'UsernameOne' fontName:'Times New Roman' position:{1536, 1978.031982421875}'

How can I display all of the strings that I have stored in this array on my screen in a column with one string on each column? I tried using a ScrollView since I have used it other places and my actual array contains about 100 strings that I need to break apart and display in a column on the users screen. Thanks.

Answer 1

The error occurs because you are adding the same SKLabelNode again and again in the for loop. Instead, you should be creating a new SKLabelNode in each iteration:

let usernameData = documents.map { $0["playername"]! }

for usernames in usernameData {
    let label = SKLabelNode(fontNamed: "Times New Roman")
    label.text = usernames as? String
    label.fontSize = 150
    label.fontColor = SKColor.white
    label.position = CGPoint(x: self.frame.midX * 1.50, y: self.contrainer.frame.maxY * 2.90)
    label.zPosition = 100
    self.moveableNode.addChild(label)

}