Crash in file Core.swift

[fred]

public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
public override func touchesBegan(_ touches: Set, with event: UIEvent) {
super.touchesBegan(touches, with: event)
initialLocation = touches.first?.location(in: view) ?? .zero
if floatingPanel.transitionAnimator != nil || floatingPanel.moveAnimator != nil {
self.state = .began
}
}
}

initialLocation = touches.first?.location(in: view) ?? .zero
In this sentence， the view of UIPanGestureRecognizer is option value