ios - UIImage 去我点击的地方(但我需要它所以你只能拖动它)

Question

我有一个 UIImage 并将其链接到我的代码中并将其命名为“Person”在我点击屏幕的那一刻，UIImage 跳转到那个位置，但我想要它，所以图像只能在我拖动它时移动。这是我的代码:

var location = CGPointMake(0, 0)

@IBOutlet var Person: UIImageView!

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {

    let touch : UITouch = touches.first as UITouch!

    location = touch.locationInView(self.view)

    Person.center = location

}

override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {

    let touch : UITouch = touches.first as UITouch!

    location = touch.locationInView(self.view)

    Person.center = location

}

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    Person.center = CGPointMake(160, 330)


}

Answer 1

我会使用手势识别器——更不用说编码了。此外，如果要移动的元素不止一个，我会使用“三步”手势。

第 1 步:用户点击 subview ，虚线边框表示 subview 处于编辑模式。

第 2 步:用户平移 subview 到父 View 中的新位置。

第 3 步:用户点击父 View 中的任何其他位置(包括接下来要编辑的新 subview )以使第一个 subview 退出编辑模式。

subview 代码:

var _editMode = false
var editMode:Bool {
    return _editMode
}
var borderPath = UIBezierPath()
var dashedBorder = CAShapeLayer()

func drawDashedBorder() {
    borderPath = UIBezierPath()
    borderPath.move(to: CGPoint(x: 3, y: 3))
    borderPath.addLine(to: CGPoint(x: self.frame.width-3, y: 3))
    borderPath.addLine(to: CGPoint(x: self.frame.width-3, y: self.frame.height-3))
    borderPath.addLine(to: CGPoint(x: 3, y: self.frame.height-3))
    borderPath.close()
    dashedBorder = CAShapeLayer()
    dashedBorder.strokeColor = UIColor.white.cgColor
    dashedBorder.fillColor = UIColor.clear.cgColor
    dashedBorder.lineDashPattern = [2, 2]
    dashedBorder.lineDashPhase = 0.0
    dashedBorder.lineJoin = kCALineJoinMiter
    dashedBorder.lineWidth = 1.0
    dashedBorder.miterLimit = 10.0
    dashedBorder.path = borderPath.cgPath
    let animation = CABasicAnimation(keyPath: "lineDashPhase")
    animation.fromValue = 0.0
    animation.toValue = 15.0
    animation.duration = 0.75
    animation.repeatCount = 10000
    dashedBorder.add(animation, forKey: "linePhase")
    self.addSublayer(dashedBorder)
    _editMode = true
}

func removeDashedBorder() {
    dashedBorder.removeFromSuperlayer()
    _editMode = false
}

这不是生产代码，所以我从来没有完全弄清楚如何让“移动虚线”动画永远运行(这可能很好，因为它可能是一个性能问题)。但是 10000 秒似乎相当慷慨用于编辑。

这是 super View 代码，假设您有 imageView1 和 imageView2 作为 subview :

var editMode = false

override func viewDidLoad() {
    super.viewDidLoad()
    let tapGesture = UITapGestureRecognizer()
    let panGesture = UIPanGestureRecognizer()
    tapGesture.numberOfTapsRequired = 1
    tapGesture.addTarget(self, action: #selector(editImage))
    self.addGestureRecognizer(tapGesture)
    panGesture.addTarget(self, action: #selector(moveImage))
    self.addGestureRecognizer(panGesture)
}

func editEye(_ recognizer:UITapGestureRecognizer) {
    let p = recognizer.location(in: self)
    if !editMode {
        if (imageView1.layer.hitTest(p) != nil) {
            imageView1.drawDashedBorder()
            self.editMode = true
        } else if (imageView2.layer.hitTest(p) != nil) {
            imageView2.drawDashedBorder()
            self.editMode = true
        }
    } else {
        if imageView1.editMode {
            imageView1.removeDashedBorder()
            self.editMode = false
        } else if imageView2.editMode {
            imageView2.removeDashedBorder()
            self.editMode = false
        }
    }
}

func moveEye(_ recognizer:UIPanGestureRecognizer) {
    let p = recognizer.location(in: self)
    if imageView1.editMode {
        imageView1.position = p
    }
    if imageView2.editMode {
        imageView2.position = p
    }
}

这可能不符合您的确切需求，但点击和平移与点击的组合似乎更自然。我敢肯定，至少，做一个“无声”的点击和平移(在用户看来他们只是在四处拖动一些东西，但他们仍然必须先点击它)更合适。