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似乎anchor pointmybuttonView的 正在根据 的位置而变化view。我希望buttonView缩小到自身的中间而不是view. 我想知道我做错了什么？或者如果我完全误解了锚点？我尝试阅读一些文章，但它们似乎暗示一个对象的锚点指的是它自己的坐标而不是它的超级视图。

import UIKit

class ViewController: UIViewController {
    var buttonView:UIView!
    var toggleButton:UIButton!
    var isVisible = false

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

        let buttonTitles = ["1", "2", "3"]
        let size:CGFloat = 100.0

        let viewSize = CGFloat(buttonTitles.count) * size
        buttonView = UIView(frame: CGRectMake(40, 40, viewSize, viewSize))

        setAnchorPoint(CGPointMake(0.5, 0), forView: buttonView)
        buttonView.layer.anchorPoint = CGPointMake(0.5, 0.0)
        view.addSubview(buttonView)

        for (index, title) in buttonTitles.enumerate() {
            let button = UIButton(type: .Custom) as UIButton
            button.frame = CGRectMake(0, size * CGFloat(index), size, size)
            button.setTitle(title, forState: .Normal)
            button.backgroundColor = UIColor.redColor()
            buttonView.addSubview(button)
        }

        toggleButton = UIButton(type: .Custom) as UIButton
        toggleButton.frame = CGRectMake(200, 100, 80, 50)
        toggleButton.setTitle("Toggle", forState: .Normal)
        toggleButton.backgroundColor = UIColor.purpleColor()
        toggleButton.addTarget(self, action: #selector(ViewController.animate), forControlEvents: .TouchUpInside)
        view.addSubview(toggleButton)
    }

    func setAnchorPoint(anchorPoint: CGPoint, forView view: UIView) {
        var newPoint = CGPointMake(view.bounds.size.width * anchorPoint.x, view.bounds.size.height * anchorPoint.y)
        var oldPoint = CGPointMake(view.bounds.size.width * view.layer.anchorPoint.x, view.bounds.size.height * view.layer.anchorPoint.y)

        newPoint = CGPointApplyAffineTransform(newPoint, view.transform)
        oldPoint = CGPointApplyAffineTransform(oldPoint, view.transform)

        var position = view.layer.position
        position.x -= oldPoint.x
        position.x += newPoint.x

        position.y -= oldPoint.y
        position.y += newPoint.y

        view.layer.position = position
        view.layer.anchorPoint = anchorPoint
    }

    func animate() {

        if (isVisible) { // collapse it
            isVisible = false

            UIView.animateWithDuration(0.5, animations: { 
                self.buttonView.transform = CGAffineTransformMakeScale(0.2, 0.2)
            })
        }

        else { // expand it
            isVisible = true

            UIView.animateWithDuration(0.5, animations: {
                self.buttonView.transform = CGAffineTransformMakeScale(1.0, 1.0)
            })
        }
    }   
}

在单击切换之前：在此处输入图像描述

点击切换后：在此处输入图像描述

4

1 回答 1

-1

没关系，原来我只是把我的buttonView's宽度设置得太大了。

于 2016-05-01T06:05:09.387 回答