NSImage in a CALayer and Liveness - swift

Question

I'm missing something here. I got Liveness to work in Interface Builder. I can draw the image in the NSView with NSImage.draw rect. So the image loads correctly. However when I put this inside a CALayer it doesn't show up.
Did I miss something about behaviour on NSView? CALayer? Layer Hosting? Or something else?
Here's the code of the view:
import Foundation
import AppKit
import QuartzCore
#IBDesignable public class CircularImageView: NSView {
var imageLayer: CALayer?
#IBInspectable public var edgeInset: CGFloat = 10
public var image: NSImage? {
didSet {
if let newImage = image {
imageLayer?.contents = newImage
}
}
}
// MARK: New in this class
private func prepareLayer() {
self.layer = CALayer()
self.wantsLayer = true
}
private func drawImage() {
// What am I doing wrong here?
var newImageLayer = CALayer()
newImageLayer.contentsGravity = kCAGravityResizeAspect
if let imageToSet = image {
newImageLayer.contents = imageToSet
}
let insetBounds = CGRectInset(self.bounds, edgeInset, edgeInset)
newImageLayer.frame = insetBounds
newImageLayer.backgroundColor = NSColor(calibratedWhite: 0.8, alpha: 1).CGColor
self.layer!.addSublayer(newImageLayer)
imageLayer = newImageLayer
}
private func test(){
image?.drawInRect(self.bounds)
}
// MARK: NSView stuff
public override init(frame frameRect: NSRect) {
super.init(frame: frameRect)
prepareLayer()
}
public required init?(coder: NSCoder) {
super.init(coder: coder)
prepareLayer()
}
public override func viewWillDraw() {
super.viewWillDraw()
drawImage()
}
public override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
// Load default test image.
println("\(self): prepareForInterfaceBuilder")
let processInfo = NSProcessInfo.processInfo()
let environment = processInfo.environment
let projectSourceDirectories : AnyObject = environment["IB_PROJECT_SOURCE_DIRECTORIES"]!
let directories = projectSourceDirectories.componentsSeparatedByString(":")
if directories.count != 0 {
let firstPath = directories[0] as! String
let imagePath = firstPath.stringByAppendingPathComponent("CircularView/Bz1dSvR.jpg")
let image = NSImage(contentsOfFile: imagePath)
image!.setName("Test Image")
self.image = image
}
}
}
Thanks in advance.

Answer 1

Okay, guys I found the answer.
I did two things wrong in this code. I was working on a layer hosting view and I simply needed a layer-backed view. I didn't new there was a difference. And before adding an NSImage to the CALayer's contents I needed to embrace it with lockFocus() and unlockFocus().
Here's the full code that solved the issue.
import Foundation
import AppKit
#IBDesignable public class CircularImageView: NSView {
var imageLayer: CALayer?
#IBInspectable public var edgeInset: CGFloat = 10
public var image: NSImage? {
didSet {
if let newImage = image {
imageLayer?.contents = newImage
}
}
}
// MARK: New in this class
private func prepareLayer() {
// I had to remove my own created layer.
self.wantsLayer = true
}
private func drawImage() {
var newImageLayer = CALayer()
newImageLayer.contentsGravity = kCAGravityResizeAspect
if let imageToSet = image {
// I didn't lock the focus on the imageToSet.
imageToSet.lockFocus()
newImageLayer.contents = imageToSet
// I didn't unlock the focus either.
imageToSet.unlockFocus()
}
let insetBounds = CGRectInset(self.bounds, edgeInset, edgeInset)
newImageLayer.frame = insetBounds
newImageLayer.backgroundColor = NSColor(calibratedWhite: 0.8, alpha: 1).CGColor
self.layer!.addSublayer(newImageLayer)
imageLayer = newImageLayer
}
// MARK: NSView stuff
public override init(frame frameRect: NSRect) {
super.init(frame: frameRect)
prepareLayer()
}
public required init?(coder: NSCoder) {
super.init(coder: coder)
prepareLayer()
}
public override func viewWillDraw() {
super.viewWillDraw()
drawImage()
}
public override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
// Load default test image.
println("\(self): prepareForInterfaceBuilder")
let processInfo = NSProcessInfo.processInfo()
let environment = processInfo.environment
let projectSourceDirectories : AnyObject = environment["IB_PROJECT_SOURCE_DIRECTORIES"]!
let directories = projectSourceDirectories.componentsSeparatedByString(":")
if directories.count != 0 {
let firstPath = directories[0] as! String
let imagePath = firstPath.stringByAppendingPathComponent("CircularView/Bz1dSvR.jpg")
let image = NSImage(contentsOfFile: imagePath)
image!.setName("Test Image")
self.image = image
}
}
}