Swift：如何使用touchesBegan / Moved管理多个可拖动的uiimageviews

Question

我刚创建了两个移动/可拖动的UIImageView，它们应该在下方更大的UIImageView上移动，如下面的屏幕截图所示：

这是我的代码：

class PhotoViewController: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate {


@IBOutlet weak var imageView: UIImageView!
@IBOutlet weak var redA: UIImageView!
@IBOutlet weak var redB: UIImageView!

var imagePicker: UIImagePickerController!
var redLocationA:CGPoint = CGPoint(x:0, y:0)
var redLocationB:CGPoint = CGPoint(x:0, y:0)

override func viewDidLoad() {
    super.viewDidLoad()
    self.redA.center = CGPointMake(80, 330)
    self.redB.center = CGPointMake(80, 360)
    // Do any additional setup after loading the view, typically from a nib.
}


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
    self.redLocationA = (touches.first?.locationInView(self.view))!
    self.redA.center = redLocationA

    self.redLocationB = (touches.first?.locationInView(self.view))!
    self.redB.center = redLocationB
}

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

    self.redLocationA = (touches.first?.locationInView(self.view))!

    if ((redLocationA.x >= 26 && redLocationA.x <= 292) && (redLocationA.y >= 71 && redLocationA.y <= 461)){
        redA.center = redLocationA
    }

    if ((redLocationB.x >= 26 && redLocationB.x <= 292) && (redLocationB.y >= 71 && redLocationB.y <= 461)){
        redB.center = redLocationB
    }

    print("redA: \(redLocationA)")
    print("redB: \(redLocationB)")
}

...
}

你可以想象当我点击一个别针然后另一个被移动到第一个的位置，我认为，因为我总是从touches: Set<UITouch>执行相同的提取。 在每次攻丝时，在没有第一个位置的情况下管理两个引脚的正确方法是什么？ 谢谢

Answer 1

如果你想按下并拖动图像，你应该为每个imageView添加panGestureRecognizer