Swift:UIPanGestureRecognizer 反向滑动错误

Question

我创建了一个UIPanGestureRecognizer，但问题是当我将 View 向右滑动时， View 会向左移动。

当我向左滑动 View 时，它会向右滑动。为什么？

let panGesture = UIPanGestureRecognizer(target: self, action: #selector(detectPan(recognizer:)))
panGesture.delaysTouchesBegan = false
panGesture.delaysTouchesEnded = false
separatorView.addGestureRecognizer(panGesture)

和我的功能:

@objc func detectPan(recognizer: UIPanGestureRecognizer) {
    switch recognizer.state {
    case .began:
        self.startingConstant = self.centerConstraint.constant
    case .changed:
        let translation = recognizer.translation(in: self.view)
        self.centerConstraint.constant = self.startingConstant + translation.x
    default:
        break
    }
}

Answer 1

我没有靠近 XCode 来测试这个，但我认为你正在反向进行数学计算:

self.centerConstraint.constant = self.startingConstant + translation.x

应该是:

self.centerConstraint.constant = self.startingConstant - translation.x