Question

我正在寻找最好的方法来反转两个UIView的位置，如果可能的话动画（首先我需要改变位置，动画是可选的）。

viewController ：

所以，我希望view1用view2来反转他的位置。 views在init的故事板中使用autolayout设置。

if state == true {
    view1 at the top
    view2 at the bot
} else {
    view 2 at the top
    view 1 at the top
}

我试图从另一个视图中取出view.frame.(x, y, width, height)并将其设置为视图，但它无法正常工作。

Answer 1

我认为最好的方法是为连接到标题的两个视图设置topConstraint，然后更改它们的值并为过渡设置动画。你可以用类似的方式做到这一点：

class MyViewController: UIViewController {

 var view1TopConstraint: NSLayoutConstraint!
 var view2TopConstraint: NSLayoutConstraint!

 override func viewDidLoad() {
    super.viewDidLoad()

   view1TopConstraint = view1.topAnchor.constraintEqualToAnchor(header.bottomAnchor, constant: 0)
    view1TopConstraint.isActive = true

  view2TopConstraint = view2.topAnchor.constraintEqualToAnchor(header.bottomAnchor, constant: view1.frame.height)
    view2TopConstraint.isActive = true
}

func changeView2ToTop() {
    UIView.animateWithDuration(0.2, animations: { //this will animate the change between 2 and 1 where 2 is at the top now
    self.view2TopConstraint.constant = 0
    self.view1TopConstraint.constant = view2.frame.height
    //or knowing that view2.frame.height represents 30% of the total view frame you can do like this as well
    //      self.view1TopConstraint.constant = view.frame.height * 0.3

    self.view.layoutIfNeeded()
   }) 
 }

您还可以在故事板中创建NSLayoutConstraint并使用插座而不是我创建的变量，或者在故事板中设置两个视图的顶部约束，然后在构建时删除＆＃34;如果你两个都做。这样你就不会有2个顶级约束而且没有约束变换

Answer 2

我做了一个例子：https://dl.dropboxusercontent.com/u/24078452/MovingView.zip

我刚创建了一个包含3个视图，标题，视图1（红色）和视图2（黄色）的故事板。然后我添加了IBoutlets并在viewDid中显示它们动画，这里是代码：

import UIKit

class ViewController: UIViewController {

    var position1: CGRect?
    var position2: CGRect?

    @IBOutlet weak var view1: UIView!
    @IBOutlet weak var view2: UIView!
    override func viewDidLoad() {
        super.viewDidLoad()

    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        position1 = view1.frame
        position2 = view2.frame
        UIView.animate(withDuration: 2.5) {
            self.view1.frame = self.position2!
            self.view2.frame = self.position1!
        }
    }


}

Answer 3

你好@Makaille我试着解决你的问题。我已经做了一个例子，它将帮助您实现所需的实现。点击此处：Source Code

我希望，它会帮助你。

@IBAction func toggle(_ sender: UIButton) {

    sender.isUserInteractionEnabled = false

    if(sender.isSelected){
        let topPinConstantValue = layout_view2TopPin.constant
        layout_view1TopPin.constant = topPinConstantValue
        layout_view2TopPin.priority = 249
        layout_view1BottomPin_to_View2Top.priority = 999

        layout_view1TopPin.priority = 999
        layout_view2BottomPin_ToView1Top.priority = 249

        UIView.animate(withDuration: 0.3, animations: {
            self.view.layoutIfNeeded()
        }, completion: { (value) in
            if(value){
                sender.isUserInteractionEnabled = true
            }
        })

    } else {
        let topPinConstantValue = layout_view1TopPin.constant
        layout_view2TopPin.constant = topPinConstantValue
        layout_view1TopPin.priority = 249
        layout_view2BottomPin_ToView1Top.priority = 999

        layout_view2TopPin.priority = 999
        layout_view1BottomPin_to_View2Top.priority = 249

        UIView.animate(withDuration: 0.3, animations: {
            self.view.layoutIfNeeded()
            }, completion: { (value) in
                if(value){
                    sender.isUserInteractionEnabled = true
                }
        })
    }

    sender.isSelected = !sender.isSelected
}

用动画反转UIView的地方

3 个答案: