自定义UISearchController动画

Question

底线问题:

如何覆盖属于UISearchController的searchBar的默认动画？

---

标准搜索控制器行为:

好的,所以我正在尝试为附加到UISearchController的UISearchBar变为活动状态时创建自定义动画.似乎标准动画期望searchBar以占据屏幕的宽度开始.动画开始时缩小搜索栏并在其右侧的取消按钮中淡入淡出.

我想要实现的目标:

我希望我的searchBar以小的状态开始,大约是屏幕宽度的一半,以便允许两个按钮放在它旁边的导航栏中.

现在动画:

当searchBar变为活动状态时,我希望动画扩展searchBar并使取消按钮淡入.

解雇动画:

当searchBar被解除时,我希望发生完全相反的动画:取消按钮淡出和searchBar缩小到它的原始大小.

---

问题:

我找到了一种方法,通过使用UISearchControllerDelegate方法presentSearchController来实现所需的呈现动画:

func presentSearchController(searchController: UISearchController) {

    // Animate Buttons
    UIView.animateWithDuration(0.1, animations: {

        // First Hide Buttons
        self.createMoxyButton.alpha = 0
        self.centerMapButton.alpha  = 0
    })

    // Animate Search Bar
    UIView.animateWithDuration(0.5, animations: {

        // Search Bar
        searchController.searchBar.frame = CGRectMake(searchController.searchBar.frame.origin.x, searchController.searchBar.frame.origin.y, self.wBounds - 40, searchController.searchBar.frame.height)
        self

    })

}

但我无法实现解雇动画.我已经尝试使用didDismissSearchController:和willDismissSearchController:委托方法但它导致奇怪的行为,并且不使用我在这些相应的委托方法中设置的帧的动画.当searchBar被解除时,它将扩展到全屏宽度,同时淡出取消按钮,然后它会立即将searchBar的帧更改回原始大小,忽略我的动画.我也尝试使用removeAllAnimation()方法尝试阻止默认动画发生,但无济于事.

func didDismissSearchController(searchController: UISearchController) {
    searchController.searchBar.layer.removeAllAnimations()

    // Animate
    UIView.animateWithDuration(0.5, animations: {

        // Show hidden buttons
        self.createMoxyButton.alpha = 1
        self.centerMapButton.alpha  = 1

        // Search Bar
        searchController.searchBar.frame = CGRectMake(searchController.searchBar.frame.origin.x, searchController.searchBar.frame.origin.y, self.wBounds - 10 - self.createMoxyButton.frame.size.width - 20 - self.centerMapButton.frame.size.width - 20, searchController.searchBar.frame.height)
        self

    })
}

解决SearchBar问题的图像

Gif动画以处于活动状态的searchBar开始,并且可以看到取消按钮

Answer 1

我不能声称这会产生超级平滑的动画，但它看起来并不可怕，并且可能会有所帮助（甚至正是您所需要的）。如果您想尝试一下，可以创建一个新项目（单视图应用程序），然后添加导航控制器作为初始控制器，并将类对象添加ViewController为其根控制器（只是为了快速获取导航栏）。下面的代码是我的完整实现ViewController

import UIKit

class ViewController: UIViewController,UISearchBarDelegate,UISearchControllerDelegate,UISearchResultsUpdating {

    lazy var createMoxyButton:UIBarButtonItem = {
        //customize this as your equire
        let button = UIBarButtonItem(title: "Done", style: .Plain, target: nil, action: nil)
        return button
    }()

    lazy var centerMapButton:UIBarButtonItem = {
        //customize this as your equire
        let button = UIBarButtonItem(title: "Done", style: .Plain, target: nil, action: nil)
        return button
        }()

    lazy var searchController:UISearchController = {
        let controller = UISearchController(searchResultsController: self)
        controller.delegate = self
        controller.searchResultsUpdater = self
        controller.dimsBackgroundDuringPresentation = false
        controller.hidesNavigationBarDuringPresentation = false
        return controller
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        self.navigationItem.titleView = self.searchController.searchBar
        self.navigationItem.rightBarButtonItems = [self.centerMapButton,self.createMoxyButton]
        self.edgesForExtendedLayout = UIRectEdge.None
        self.searchController.searchBar.delegate = self
    }

    func updateSearchResultsForSearchController(searchController: UISearchController) {

    }

    func searchBarTextDidBeginEditing(searchBar: UISearchBar) {
        //this needs to be done because in shouldEndEditing
        //we need to set it to false to smooth animation
        searchBar.showsCancelButton = true
        self.navigationItem.setRightBarButtonItems(nil, animated: true)
    }

    func searchBarShouldEndEditing(searchBar: UISearchBar) -> Bool {
        searchBar.showsCancelButton = false
        self.navigationItem.rightBarButtonItems = [self.centerMapButton,self.createMoxyButton]
        return true
    }
}