Custom SKShapeNode Child Not Appearing

Question

I am trying to make a number appear in the middle of an SKShapeNode. However, for some reason when I add the SKLabelNode as a child of the shape node, it does not appear despite the fact that the SKShapeNode does appear. I added the same label as a child of the SKScene and it appeared just fine. Here is the code for the custom class:

class Dot: SKShapeNode {
    var numLabel = SKLabelNode(fontNamed: "MarkerFelt-Wide")
    func setNumber(i: Int) {
        numLabel.text = String(i)
        numLabel.fontColor = UIColor.whiteColor()
        numLabel.fontSize = 200
        numLabel.setScale(numLabel.frame.width / self.frame.width / 2)
        numLabel.position = CGPointMake(self.frame.midX ,self.frame.midY)
        self.addChild(numLabel)
    }
}

I call dot.setNumber(1) but nothing happens. Please let me know if you find the issue. Thanks!

Answer 1

After much trial and error, reteaching myself how SKNodes work differently than UIViews, I think the reason for your problem is as follows: the .position property in sprite kit is not the position of the corner of the node, but the center of it. Also, when setting an SKNode as a child of another SKNode, its position is based on its parent, not the scene. So instead of setting the numLabel to midX and midY it should rather be:

numLabel.position = CGPointMake(0, 0)

However, for some reason the y value is still not correct, at least in the code that I am using. It may be due to the way that you are scaling the numLabel. So I sort of fixed it with the code:

numLabel.position = CGPointMake(0, -(numLabel.frame.height / 2))

Still, this is not perfect.

With this new information, if you are still not able to figure it out, I will look further into getting the exact position. But keep in mind my answer at the beginning of this post.