Question

我在stackoverflow上提出了一个问题，并得到了一个完整的答案。

要获取UIPanGestureRecognizer的起点和终点，请使用代码：

var view = UIView()

func panGestureMoveAround(gesture: UIPanGestureRecognizer) {

    var locationOfBeganTap: CGPoint

    var locationOfEndTap: CGPoint

    if gesture.state == UIGestureRecognizerState.Began {
        locationOfBeganTap = gesture.locationInView(view)
    } else if gesture.state == UIGestureRecognizerState.Ended {
        locationOfEndTap = gesture.locationInView(view)
    }
}

为了更好地观看，我会绘制一个捕捉起点的矩形并自动调整大小以完成移动。

我如何绘制一个矩形作为起点并按照我的动作结束手势？

Answer 1

你需要创建一个UIView的子类，像RectView一样调用它，就像这样：

@IBDesignable
class RectView: UIView {
    @IBInspectable var startPoint:CGPoint?{
        didSet{
            self.setNeedsDisplay()
        }
    }

    @IBInspectable var endPoint:CGPoint?{
        didSet{
            self.setNeedsDisplay()
        }
    }

    override func drawRect(rect: CGRect) {
        if (startPoint != nil && endPoint != nil){
            let path:UIBezierPath = UIBezierPath(rect: CGRectMake(min(startPoint!.x, endPoint!.x),
            min(startPoint!.y, endPoint!.y),
            fabs(startPoint!.x - endPoint!.x),
            fabs(startPoint!.y - endPoint!.y)))
        path.stroke()
    }
    }

}

然后在您的视图控制器中，您可以说：

@IBAction func panGestureMoveAround(sender: UIPanGestureRecognizer) {
        var locationOfBeganTap: CGPoint

        var locationOfEndTap: CGPoint

        if sender.state == UIGestureRecognizerState.Began {
            locationOfBeganTap = sender.locationInView(rectView)
            rectView.startPoint = locationOfBeganTap
            rectView.endPoint = locationOfBeganTap

        } else if sender.state == UIGestureRecognizerState.Ended {
            locationOfEndTap = sender.locationInView(rectView)
                        rectView.endPoint = sender.locationInView(rectView)
        } else{
            rectView.endPoint = sender.locationInView(rectView)
        }
    }

绘制一个矩形作为起点并按照我的动作结束Swift中的手势

1 个答案: