如何通过按钮开启/关闭ARKit？附实现代码求优化建议

Hey there! Let's work through this to get a cleaner, more reliable ARKit toggle for your button. First, let's quickly note the issues with your current approaches:

• Your first arSwitch() function has a couple of problems: the case labels have inconsistent capitalization (btnPressed vs btnpressed), and it's hardcoding boolean values instead of toggling the current state. That won't work for a proper on/off switch.
• The second approach is closer, but sceneView.scene.stop() isn't a valid method—SCNScene doesn't have a stop() function. To control ARKit, you need to interact with the ARSession rather than just the scene.

Here's a more robust, Apple-recommended implementation that handles state properly and uses ARKit's native APIs:

// Connect these outlets to your storyboard elements
@IBOutlet weak var arToggleSwitch: UISwitch!
@IBOutlet weak var sceneView: ARSCNView!

// Store your AR and non-AR scenes (adjust the non-AR one to fit your needs)
private let arScene = ARSCNScene()
private let staticScene = SCNScene(named: "StaticScene.scn")! // Or use an empty scene if needed

// Track the current state of the AR session to avoid mismatches
private var isARSessionActive = false

@IBAction func arButtonTapped(_ sender: Any) {
    // Toggle the active state first
    isARSessionActive = !isARSessionActive
    arToggleSwitch.isOn = isARSessionActive
    
    if isARSessionActive {
        // Start the AR session with a standard tracking configuration
        let arConfig = ARWorldTrackingConfiguration()
        sceneView.session.run(arConfig)
        
        // Switch to the AR scene and enable AR-specific UI
        sceneView.scene = arScene
        sceneView.showsStatistics = true // Optional: Show FPS/tracking info
    } else {
        // Pause the AR session to stop tracking and save resources
        sceneView.session.pause()
        
        // Switch back to your non-AR scene and disable AR UI
        sceneView.scene = staticScene
        sceneView.showsStatistics = false
    }
}

Why this works better: #

• State consistency: We use a dedicated isARSessionActive variable to keep track of whether AR is running, so the switch and actual session state never get out of sync.
• Proper ARSession control: Apple recommends using session.run() and session.pause() to manage ARKit's lifecycle—this stops camera capture and motion tracking when paused, which saves battery and processing power.
• Clear scene separation: It explicitly swaps between your AR and non-AR scenes, making the logic easy to follow and extend later.

A few extra tips: #

• If you don't need a separate non-AR scene, you can just pause the session and leave the current scene (but the camera feed will freeze).
• Always pause the AR session when your view disappears (add sceneView.session.pause() to viewWillDisappear) to prevent background resource usage.
• Make sure you've requested camera permissions in your Info.plist (add NSCameraUsageDescription)—ARKit won't run without user approval.

内容的提问来源于stack exchange，提问作者jon