如何防止意外触摸触发 swift 4.2 中的 touchesBegan?

How to prevent that an accidental touch triggering the touchesBegan in swift 4.2?

我有一个使用 touchesBegan 为用户执行操作的应用程序。但是,有时触摸屏幕只是留下一个textField。

有什么方法可以将 touchesBeagan 设置为仅在保持触摸 2 或 3 秒后启动,如果触摸小于此时间,则触发 resignFirstResponder 而不是触发操作?

为了帮助理解这里是我的触摸方法:

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    Feedback.share.hapticFeedback()
    startPoint = nil
    guard let touch = touches.first else {return}
    startPoint = touch.location(in: imageView)

    //Initialize whatever you need to begin showing selected rectangle below.
    rectShapeLayer.path = nil
    imageView.layer.addSublayer(rectShapeLayer)
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    guard let touch = touches.first, let startPoint = startPoint else {return}
    let currentPoint: CGPoint
    if let predicted = event?.predictedTouches(for: touch), let lastPoint = predicted.last {
        currentPoint = lastPoint.location(in: imageView)
    } else {
        currentPoint = touch.location(in: imageView)
    }
    let frame = rect(from: startPoint, to: currentPoint)

    //Show bounding box
    rectShapeLayer.path = UIBezierPath(rect: frame).cgPath
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    guard let touch = touches.first, let startPoint = startPoint else {return}
    let currentPoint = touch.location(in: imageView)
    let frame = rect(from: startPoint, to: currentPoint)

    //Remove bounding box but take snapshot of selected `CGRect` by frame
    rectShapeLayer.removeFromSuperlayer()
    let memeImage = imageView.snapshot(rect: frame, afterScreenUpdates: true)

    save(imageView: imageView, image: memeImage)

}

我找到了一种方法来保证触摸屏幕时它只执行 resignFirstResponder 而不是其他函数。

我只更改了 touchesEnded(_:) 方法添加了一个 "if frame.size.width < 1".

这对我来说效果很好。

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    guard let touch = touches.first, let startPoint = startPoint else {return}
    let currentPoint = touch.location(in: ivPhoto)
    let frame = rect(from: startPoint, to: currentPoint)

    rectShapeLayer.removeFromSuperlayer()

    if frame.size.width < 1 {
        tfTop.resignFirstResponder()
        tfBottom.resignFirstResponder()
    } else {

        let memeImage = ivPhoto.snapshot(rect: frame, afterScreenUpdates: true)

        saveCrop(cropImage: memeImage)
    }
}