Mac开发跬步积累(二):NSViewController 转场动画精耕细作

   1. 内嵌在同一个窗口中形式弹出新的ViewController
    open func presentViewControllerAsSheet(_ viewController: NSViewController)
    
   2. 新窗口的形式弹出新的ViewController
    open func presentViewControllerAsModalWindow(_ viewController: NSViewController)

   3. Popover的形式弹出新的ViewController
    open func presentViewController(_ viewController: NSViewController, asPopoverRelativeTo positioningRect: NSRect, of positioningView: NSView, preferredEdge: NSRectEdge, behavior: NSPopover.Behavior)

   4. 从fromViewController转换到toViewController
    open func transition(from fromViewController: NSViewController, to toViewController: NSViewController, options: NSViewController.TransitionOptions = [], completionHandler completion: (() -> Swift.Void)? = nil)

 @available(OSX 10.10, *)
    public struct TransitionOptions : OptionSet {

        public static var crossfade: NSViewController.TransitionOptions { get }
        
        public static var slideUp: NSViewController.TransitionOptions { get }

        public static var slideDown: NSViewController.TransitionOptions { get }

        public static var slideLeft: NSViewController.TransitionOptions { get }

        public static var slideRight: NSViewController.TransitionOptions { get }

        public static var slideForward: NSViewController.TransitionOptions { get }

        public static var slideBackward: NSViewController.TransitionOptions { get }

        public static var allowUserInteraction: NSViewController.TransitionOptions { get }
    }

class ViewController: NSViewController {
 
1. 从Storyboard中的CustomView 连线的控件属性,用来作为容器视图,显示每个ChildViewController的内容      
    @IBOutlet weak var containView: MYContainView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
2. 添加需要切换的子控制器: RedController 和BlueController 为自定义的两个控制器,仅显示不同的视图颜色.
        addChildViewController(RedController())
        addChildViewController(BlueController())
3. 需要将第一个ChildViewController的view添加到容器视图中;
        containView.addSubview(childViewControllers[0].view)
4. 设置容器视图的颜色
        containView.layer?.backgroundColor = NSColor.orange.cgColor
    
    }
5. 点击下一个按钮, 从RedController 切换到BlueController
    @IBAction func clickBtn(_ sender: Any) {
        transition(from: childViewControllers[0], to: childViewControllers[1], options: .slideLeft, completionHandler: nil)
    }
6. 点击上一个按钮, 从BlueController 切换到RedController
    @IBAction func clickUpButton(_ sender: Any) {
        transition(from: childViewControllers[1], to: childViewControllers[0], options: .slideRight, completionHandler: nil)
    }
}
6. 修改4,5 步骤中的option 参数,可以实现不同的transition 效果.

 @IBAction func presentTest(_ sender: Any) {
        let greenVC = GreenController()
       1. 以AsSheet方式弹出控制器
        presentViewControllerAsModalWindow(greenVC)
    }

        let greenVC = GreenController()
       1. 以Popover方式弹出控制器
        presentViewController(greenVC, asPopoverRelativeTo: sender.bounds, of: sender, preferredEdge: NSRectEdge.maxX, behavior: NSPopover.Behavior.transient)

public protocol NSViewControllerPresentationAnimator : NSObjectProtocol {
1. present 动画时,执行这个方法,因此在这个方法中实现自定义的动画效果
    public func animatePresentation(of viewController: NSViewController, from fromViewController: NSViewController)

2. dismiss动画时,执行这个方法 ,在这个方法中可以实在自定义的动画效果
    public func animateDismissal(of viewController: NSViewController, from fromViewController: NSViewController)
}

class PresentAnimator: NSObject {
  
}
// MARK:  NSViewControllerPresentationAnimator
extension PresentAnimator: NSViewControllerPresentationAnimator{
    func animatePresentation(of viewController: NSViewController, from fromViewController: NSViewController) {
        // 这里实现present的动画效果
        /**viewController: 将要被present出来的视图控制器, fromViewcontroller --> presented动作 ---> viewController */
        1. 获取容器view
        let containerView = fromViewController.view
        
        2. 计算最终显示的frame
        let finalFrame = NSInsetRect(containerView.bounds, 50, 50)
        3. 需要显示的view
        let modalView = viewController.view
        
        4. 设置将要显示视图的初始frame
        modalView.frame = finalFrame
        modalView.setFrameOrigin(NSMakePoint(finalFrame.origin.x, finalFrame.origin.y - 200))

        5 .添加视图到容器视图中
        containerView.addSubview(modalView)

        6. 执行动画效果
        NSAnimationContext.runAnimationGroup({ (animationContext) in
            animationContext.duration = 0.5
            modalView.animator().frame = finalFrame
            
        }, completionHandler: nil)    
    }
    
    func animateDismissal(of viewController: NSViewController, from fromViewController: NSViewController) {
        // 这里实现dismiss时的动画效果
        1. 获取开始动画的frame
        let startFrame = viewController.view.frame
        2. 执行动画
        NSAnimationContext.runAnimationGroup({ (animationContext) in
            animationContext.duration = 0.5
            viewController.view.animator().setFrameOrigin(NSMakePoint(startFrame.origin.x, startFrame.origin.y - fromViewController.view.bounds.size.height - 100))
        }) {
       3. 动画完成后,移除子视图
            viewController.view.removeFromSuperview()
        }
    }
}