👀 Views: 59 💬 Answers: 1 📅 Created: 2025-06-12

macos cocoa nsview swift

I've been struggling with this for a few days now and could really use some help. I'm experiencing a question with a custom `NSView` subclass where the drawing isn't updating properly when the view is resized on macOS 13.6. I've overridden the `draw(_:)` method to perform some custom drawing, but when I resize the window, the contents do not redraw as expected, leading to visual artifacts. Here’s a simplified version of my `NSView` subclass: ```swift class CustomDrawingView: NSView { override func draw(_ dirtyRect: NSRect) { super.draw(dirtyRect) NSColor.blue.setFill() dirtyRect.fill() // Fills the dirty rectangle with blue // Add custom drawing logic here } } ``` I’ve also set the view to `wantsLayer = true` in the `init` method, but that doesn’t seem to help. I tried calling `setNeedsDisplay(_:)` in `viewDidAppear` to force a redraw, but the question continues when I resize the window. I also noticed that when I resize the window slowly, the content appears flickered, as if it’s not redrawing correctly. I’ve checked the constraints in Interface Builder, and everything seems fine. Here is how I initialize the view in my view controller: ```swift class ViewController: NSViewController { override func viewDidLoad() { super.viewDidLoad() let customView = CustomDrawingView(frame: self.view.bounds) customView.autoresizingMask = [.width, .height] self.view.addSubview(customView) } } ``` I’m unsure if I’m missing something regarding how the drawing system works on macOS or if there’s a better approach to ensure the view updates properly on resize. Has anyone encountered a similar scenario or have suggestions for resolving this? For context: I'm using Swift on Windows. I'd really appreciate any guidance on this. I'm working on a CLI tool that needs to handle this. What am I doing wrong? I'm working in a CentOS environment. Hoping someone can shed some light on this. The stack includes Swift and several other technologies.