根据滚动视图使用自动布局水平滚动更改视图的高度和宽度 [英] Change height and width of view according to scrollview scroll horizontally using auto layout

问题描述

容器视图层次结构:-

• 容器视图
  • 滚动视图
    • 向左查看
    • 查看中心
    • 查看权限
    • Container View
      • Scrollview
        • view left
        • view center
        • view right

        我需要根据scrollview水平滚动来更改FloatingBottomView的height和width约束.

        I need to change height and width constrain of FloatingBottomView according to scrollview scroll horizontally.

        初始出口:-

        @IBOutlet weak var constantFloatingBottomViewWidth: NSLayoutConstraint! // 300
        @IBOutlet weak var constantFloatingBottomViewHeight: NSLayoutConstraint! // 70
        
        override func viewWillAppear(_ animated: Bool) {
                 self.scrollView.contentOffset.x = self.view.bounds.width
                 // view center in scrollview
        }
        
        func scrollViewDidScroll(_ scrollView: UIScrollView) {
             if scrollView.contentOffset.x < self.view.bounds.width {
                // when scrollview move view center to view left, constantFloatingBottomViewWidth and height goes to down at some point  
             }
             else if scrollView.contentOffset.x > self.view.bounds.width {
               // when scrollview move view left to view center, constantFloatingBottomViewWidth & height goes up to same point range while it down and back to original constantFloatingBottomViewWidth and height
             }
        }
        

        我尝试使用这种方法在scrollViewDidScroll方法中获得一定的比例. 从左向右快速滚动，反之亦然

        i have tried using this way to get some scale in scrollViewDidScroll method. scroll quick left to right or vice-versa did not get exactly out-put

        let scale =  abs(scrollView.contentOffset.x / self.view.bounds.width)
                    print("scale:=\(scale)")
        

        推荐答案

        我认为您需要提供这样的按钮动画

        I think you need to give button animation like this

        为此，您无需执行任何操作，只需将动画添加到按钮即可，如下所示 在viewDidLoad中调用setupButtonanimation

        For this you have nothing to do just add animation to button like follow call setupButtonanimation in viewDidLoad

         func setupButtonAnimation()
                {
                    let animation = CABasicAnimation.init(keyPath: "transform.scale")
                    animation.fromValue = 1.0
                    animation.toValue = 0.45
                    animation.duration = 1.0
                    //Set the speed of the layer to 0 so it doesn't animate until we tell it to
                    self.btn1.layer.speed = 0.0;
                    self.btn1.layer.add(animation, forKey: "transform");
                }
                func scrollViewDidScroll(_ scrollView: UIScrollView)
                {
                    let screenSize = self.view.bounds.size
                    if let btn =  self.btn1
                    {
                        var factor:CGFloat = 1.0
                        factor = scrollView.contentOffset.x / screenSize.width
                        if factor > 1
                        {
                                factor = 2 - factor
                        }
                        print(factor)
                        //This will change the size
                        let timeOffset = CFTimeInterval(1-factor)
                        btn.layer.timeOffset = timeOffset
                       }
                }
        

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