Handle trackpad and mouse input

1:49 - UIHoverGestureRecognizer

let controlsHover = UIHoverGestureRecognizer(target: self, action: #selector(handleHover))

@objc func handleHover(_ recognizer: UIHoverGestureRecognizer) {
    switch recognizer.state {
    case .began:
        // Pointer entered our view - show controls
        self.showsPlaybackControls = true
    case .ended:
        // Pointer exited our view - hide controls
        self.showsPlaybackControls = false
    default:
        break
    }
}

5:33 - prefersPointerLocked

class GameViewController: UIViewController {
    
    var shouldLockPointer: Bool = true
    
    override var prefersPointerLocked: Bool {
        return self.shouldLockPointer
    }
    
    func disablePointerLock() {
        self.shouldLockPointer = false
        self.setNeedsUpdateOfPrefersPointerLocked()
    }
}

5:53 - UIPointerLockState.isLocked

if let pointerLockState = self.window.windowScene?.pointerLockState {
    self.observer = notificationCenter.addObserver(forName: UIPointerLockState.didChangeNotification,
                                                   object: pointerLockState,
                                                   queue: OperationQueue.main) { (note) in
        guard let lockState = note.object as? UIPointerLockState else { return }
        gameEngine.performExpensiveOperationWhile(lockState.isLocked)
    }
}

9:54 - UIPanGestureRecognizer.allowedScrollTypesMask

// Enable scroll input for touch surface devices
    
self.drawerPan.allowedScrollTypesMask = [.continuous]
        

// Enable scroll input for scroll wheel devices as well

self.pullToRefreshPan.allowedScrollTypesMask = [.all]

14:48 - Requiring a 3rd mouse button click

self.thirdMouseButtonTap.buttonMaskRequired = .button(3)

15:07 - Changing response for .alternate keyboard modifier

func handleHover(_ recognizer: UIHoverGestureRecognizer) {
        
    // Show chapter controls if alt is pressed
    let showChapterControls = recognizer.modifierFlags.contains(.alternate)
        
    // ...
}

16:38 - Only handle secondary clicks

class SecondaryClickGesture: UIGestureRecognizer {
    
    override func shouldReceive(_ event: UIEvent) -> Bool {
        // Must look at the event’s mask, not the gesture’s 
        return event.buttonMask == .secondary
    }
    
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
        // Touch handling code ...
    }
}

17:36 - Only handle secondary clicks or control clicks

class SecondaryClickGesture: UIGestureRecognizer {
    
    override func shouldReceive(_ event: UIEvent) -> Bool {
        // Must look at the event’s properties, not the gesture’s
        let secondaryClick = event.buttonMask == .secondary

        let controlClick = event.buttonMask == .primary && event.modifierFlags == .control 

        return secondaryClick || controlClick
    }
    
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
        // Touch handling code ...
    }
}

18:10 - Only receive hover events with the .alternate modifier pressed

let ccHover = UIHoverGestureRecognizer(target: self, 
                                       action: #selector(handleClosedCaptionHover))

ccHover.delegate = self
    
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, 
                       shouldReceive event: UIEvent) -> Bool {

    if gestureRecognizer == self.closedCaptionHover {
        return event.modifierFlags.contains(.alternate)
    }

    return true
}