ARKit uses "UIView" as contents in "SCNNode" - ios

Question

I have an odd problem, or maybe what I am doing is odd.
I have an ARKit app that displays a SCNNode with a data view embedded when a barcode is detected. When the data view is tapped I want to detach it from the node and add it as a subview to the main view. When tapped again I want to re attach it to the SCNNode.
I found this code that does at least part of what I want.
My app works well the first time. The data appears in the SCNNode:
{
let transform = anchor.transform
let label = SimpleValueViewController(nibName: "SimpleValueViewController", bundle: nil)
let plane = SCNPlane(width: self.sceneView.bounds.width/2000, height: self.sceneView.bounds.height/2000/2) //was sceneView
label.update(dataItem.title!, andValue: dataItem.value!, withTrend: dataItem.trend)
label.delegate = self
plane.firstMaterial?.blendMode = .alpha
plane.firstMaterial?.diffuse.contents = label.view //self.contentController?.view
let planeNode = SCNNode(geometry: plane)
planeNode.opacity = 0.75
planeNode.simdPosition = float3(transform.columns.3.x + ( base * count), 0, transform.columns.3.z)
node.addChildNode(planeNode)
childControllers[label] = planeNode
label.myNode = planeNode
label.parentNode = node
if("Speed" == anchorLabels[anchor.identifier]!) {
let constraint = SCNBillboardConstraint()
planeNode.constraints = [constraint]
}
count += 1
}
SimpleValueViewController has a tap recognizer that toggles between being a subview and being inside the node.
Here is the problem.
It comes up fine. The view is inside the node.
When tapped it gets attached to the main view.
When tapped again the node just shows a white square and taps no longer work.
I finally gave up and recreate a new viewController, but it still occasionally fails with only a white square:
Here is the code to detach/attach It is pretty messy as I have been pounding on it for a while:
func detach(_ vc:Detachable) {
if let controller = vc as? SimpleValueViewController {
controller.view.removeFromSuperview();
self.childControllers.removeValue(forKey: controller)
let node = controller.myNode
let parent = controller.parentNode
let newController = SimpleValueViewController(nibName: "SimpleValueViewController", bundle: nil)
if let v = newController.view {
print("View: \(v)")
newController.myNode = node
newController.parentNode = parent
newController.update(controller.titleString!, andValue: controller.valueString!, withTrend: controller.trendString!)
newController.delegate = self
newController.scaley = vc.scaley
newController.scalex = vc.scalex
newController.refreshView()
let plane = node?.geometry as! SCNPlane
plane.firstMaterial?.blendMode = .alpha
plane.firstMaterial?.diffuse.contents = v
// newController.viewWillAppear(false)
newController.parentNode?.addChildNode(newController.myNode!)
newController.attached = false;
self.childControllers[newController] = node
}
} else {
print("Not a know type of controller")
}
}
func attach(_ vc:Detachable) {
DispatchQueue.main.async {
if let controller = vc as? SimpleValueViewController {
self.childControllers.removeValue(forKey: controller)
let newController = SimpleValueViewController(nibName: "SimpleValueViewController", bundle: nil)
let node = controller.myNode
let parent = controller.parentNode
let scaleX = vc.scalex!/self.view.frame.size.width
let scaleY = vc.scaley!/self.view.frame.size.height
let scale = min(scaleX, scaleY)
let transform = CGAffineTransform(scaleX: scale, y: scale)
newController.view.transform = transform
newController.myNode = node
newController.parentNode = parent
newController.update(controller.titleString!, andValue: controller.valueString!, withTrend: controller.trendString!)
newController.delegate = self
newController.scaley = vc.scaley
newController.scalex = vc.scalex
node?.removeFromParentNode()
self.childControllers[newController] = node
newController.attached = true
self.view.addSubview(newController.view)
} else {
print("Not a know type of controller to attach")
}
}
}
I was thinking it was a timing issue as loading a view from a nib is done lazily so I put in a sleep for 1 second after the SimpleValueViewController(nibName: "SimpleValueViewController", bundle: nil) but that did not help.
Anything else I can try? I am way off base? I would like not to have to recreate the view controller every time the data is toggled.
Thanks in Advance.
Render functions:
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
// func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {
// updateQueue.async {
//Loop through the near and far data and add stuff
let data = "Speed" == anchorLabels[anchor.identifier]! ? nearData : farData
let base = "Speed" == anchorLabels[anchor.identifier]! ? 0.27 : 0.2 as Float
print ("Getting Node for: " + self.anchorLabels[anchor.identifier]!)
var count = 0.0 as Float
for dataItem in data {
let transform = anchor.transform
let label = SimpleValueViewController(nibName: "SimpleValueViewController", bundle: nil)
let plane = SCNPlane(width: self.sceneView.bounds.width/2000, height: self.sceneView.bounds.height/2000/2) //was sceneView
label.update(dataItem.title!, andValue: dataItem.value!, withTrend: dataItem.trend)
label.delegate = self
plane.firstMaterial?.blendMode = .alpha
plane.firstMaterial?.diffuse.contents = label.view //self.contentController?.view
let planeNode = SCNNode(geometry: plane)
planeNode.opacity = 0.75
planeNode.simdPosition = float3(transform.columns.3.x + ( base * count), 0, transform.columns.3.z)
node.addChildNode(planeNode)
childControllers[label] = planeNode
label.myNode = planeNode
label.parentNode = node
if("Speed" == anchorLabels[anchor.identifier]!) {
let constraint = SCNBillboardConstraint()
planeNode.constraints = [constraint]
}
count+=1
}
and update
func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {
guard currentBuffer == nil else {
return
}
self.updateFocusSquare(isObjectVisible: false)
// Retain the image buffer for Vision processing.
self.currentBuffer = sceneView.session.currentFrame?.capturedImage
classifyCurrentImage()
}
ClassifyCurrentImage is where the barcode recognizer lives. If a barcode is found it adds an anchor at the spot in the scene.