如何更改 CGRect 的 x 和 y？

Question

我画了一个矩形。当我触摸屏幕时，我可以改变宽度和高度。默认情况下，我让 x = 50，y = self.view.frame.height/2。我需要相对于 x 和 y 拉伸矩形。如何更改 x 和 y？

var scanRectangleRect = CGRect.zero
var scanRectangle: UIView = UIView()


func drawLine() {
    self.view.addSubview(scanRectangle)
    scanRectangle.backgroundColor = UIColor.gray
    scanRectangleRect = CGRect(x: 50, y: self.view.frame.height/2, width: 400, height: 150)

    scanRectangle.frame  = scanRectangleRect
    scanRectangle.center = CGPoint(x: scanRectangle.center.x, y: self.view.frame.height/2)
    scanRectangle.isHidden = false
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    scanRectangle.frame.size.height += 10
    scanRectangle.frame.size.width += 10
}

Answer 1

scanRectangle.frame.origin.x += 10
scanRectangle.frame.origin.y += 10

见https://developer.apple.com/documentation/coregraphics/cgrect/1454354-origin

如果您想增加矩形但保持其在同一位置居中：

let delta = 10

scanRectangle.frame.origin.x -= delta / 2
scanRectangle.frame.origin.y -= delta / 2
scanRectangle.frame.size.width += delta
scanRectangle.frame.size.height += delta

或

scanRectangle.frame = scanRectangle.frame.insetBy(dx: -10, dy: -10)

Answer 2

scanRectangle.frame.origin.x += 10;
scanRectangle.frame.origin.y += 10;

这是你要的吗？

Answer 3

let distance: CGFloat = 10
scanRectangle.frame = CGRect(x: scanRectangle.frame.origin.x + distance, 
                             y: scanRectangle.frame.origin.y + distance, 
                         width: scanRectangle.frame.size.width - distance, 
                        height: scanRectangle.frame.size.height - distance)

我想你的意思是在某个基点上缩放矩形。

如何更改 CGRect 的 x 和 y？

How to change x and y of CGRect?

ios

cgrect

swift