How to customize disclosure cell in view-based NSOutlineView

Question

I\'m trying to customize the disclosure arrow appearance in my view-based NSOutlineView. I saw that it\'s recommended to use

- (void)outlineView:(NSOutlineVi         


        

Answer 1

For Swift 4.2 macOS 10.14, @WetFish's answer can be implemented as follows:

class SidebarView: NSOutlineView {

  override func makeView(withIdentifier identifier: NSUserInterfaceItemIdentifier, owner: Any?) -> NSView? {
    let view = super.makeView(withIdentifier: identifier, owner: owner)

    if identifier == NSOutlineView.disclosureButtonIdentifier {
      if let btnView = view as? NSButton {
        btnView.image = NSImage(named: "RightArrow")
        btnView.alternateImage = NSImage(named: "DownArrow")

        // can set properties of the image like the size
        btnView.image?.size = NSSize(width: 15.0, height: 15.0)
        btnView.alternateImage?.size = NSSize(width: 15.0, height: 15.0)
      }
    }
    return view
  }

}

Looks quite nice!