Intermittent UI Glitch in Legacy macOS App When Adapting for Mobile Compatibility
I'm maintaining legacy code that I'm trying to configure I need some guidance on I'm reviewing some code and I'm stuck on something that should probably be simple. Currently developing a legacy macOS application intended for mobile compatibility, I've run into an odd UI glitch. As I was adapting the user interface, I noticed that some components fail to render correctly when switching between views. For instance, transitioning from a settings view back to the main view occasionally results in misaligned buttons and overlapping labels. The app is built using AppKit, and I've attempted several approaches to debug this. Initially, I verified that layout constraints were set up appropriately. Here's a snippet of the relevant code where I configure the views: ```swift let mainView = NSView() let button = NSButton(title: "Save", target: self, action: #selector(saveSettings)) mainView.addSubview(button) NSLayoutConstraint.activate([ button.centerXAnchor.constraint(equalTo: mainView.centerXAnchor), button.topAnchor.constraint(equalTo: mainView.topAnchor, constant: 20) ]) ``` Even though the constraints appear solid, I started to suspect that the view lifecycle might not be refreshing correctly. To investigate further, I added logging to track when the views appear and disappear: ```swift override func viewWillAppear() { super.viewWillAppear() print("Main view will appear") } override func viewWillDisappear() { super.viewWillDisappear() print("Main view will disappear") } ``` Despite this, the logs indicate that the views are properly initialized, but the glitches persist sporadically. I've also experimented with calling `setNeedsDisplay(_:)` on the main view after transitions, but that hasn’t resolved the issue either. With the new mobile compatibility, I suspect that the Auto Layout behavior under varying screen sizes may be a contributing factor. I’ve explored the possibility of using `NSAnimationContext` to manage view transitions more smoothly. Implementing it like so: ```swift NSAnimationContext.runAnimationGroup({ context in context.duration = 0.25 mainView.animator().alphaValue = 1.0 }, completionHandler: nil) ``` While the animation seems to enhance the transition visually, it hasn't fixed the alignment issues. Any insights into potential pitfalls or best practices for managing view states in this context would be much appreciated. Is there a way to ensure that the views are always in a consistent state when adapting a legacy app for mobile? I’m open to any debugging strategies or architectural suggestions that could help resolve this. I'd really appreciate any guidance on this. I recently upgraded to Swift stable. What's the correct way to implement this? This issue appeared after updating to Swift LTS. Thanks for taking the time to read this! I'm coming from a different tech stack and learning Swift. Could this be a known issue? Any ideas how to fix this?