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[SwiftUI教程]9、与UIKit接口

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SwiftUI可与所有Apple平台上的现有UI框架无缝协作。例如,您可以在SwiftUI视图中放置UIKit视图和视图控制器,反之亦然。

本教程将向您展示如何从主屏幕转换特色地标以包装和的实例您将使用显示SwiftUI视图的轮播,并使用状态变量和绑定来协调整个用户界面中的数据更新。UIPageViewControllerUIPageControlUIPageViewController

按照步骤构建此项目,或者下载完成的项目以自行探索。

预计的时间:25分钟
项目文件:https://docs-assets.developer.apple.com/published/113d95da00/InterfacingWithUIKit.zip

一、创建视图以表示UIPageViewController

要在SwiftUI中表示UIKit视图和视图控制器,可以创建符合协议的类型您的自定义类型创建和配置它们所代表的UIKit类型,而SwiftUI管理它们的生命周期并在需要时更新它们。UIViewRepresentableUIViewControllerRepresentable

第1步

创建一个名为的新SwiftUI视图文件,并将类型声明为符合PageViewController.swiftPageViewControllerUIViewControllerRepresentable.

页面视图控制器存储一组实例。这些是在地标之间滚动的页面。UIViewController

接下来,添加协议的两个要求UIViewControllerRepresentable

1 import SwiftUI
2 import UIKit
3 
4 struct PageViewController: UIViewControllerRepresentable {
5     var controllers: [UIViewController]
6 }

第2步

添加一个使用所需配置创建方法makeUIViewController(context:)UIPageViewController

当SwiftUI准备好显示视图时,它会调用此方法一次,然后管理视图控制器的生命周期。

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeUIViewController(context: Context) -> UIPageViewController {
 8         let pageViewController = UIPageViewController(
 9             transitionStyle: .scroll,
10             navigationOrientation: .horizontal)
11 
12         return pageViewController
13     }
14 }

第3步

添加一个方法,方法调用以在数组中显示第一个视图控制器以供显示。updateUIViewController(_:context:)setViewControllers(_:direction:animated:)

创建另一个SwiftUI视图以显示您的视图。UIViewControllerRepresentable

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeUIViewController(context: Context) -> UIPageViewController {
 8         let pageViewController = UIPageViewController(
 9             transitionStyle: .scroll,
10             navigationOrientation: .horizontal)
11 
12         return pageViewController
13     }
14 
15     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
16         pageViewController.setViewControllers(
17             [controllers[0]], direction: .forward, animated: true)
18     }
19 }

第4步

创建一个名为的新SwiftUI视图文件,并更新要声明为子视图类型PageView.swiftPageViewPageViewController

请注意,通用初始化程序采用一组视图,并将每个视图嵌套在一个视图中是一个子类,表示UIKit上下文中的SwiftUI视图。UIHostingControllerUIHostingControllerUIViewController

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5 
 6     init(_ views: [Page]) {
 7         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 8     }
 9 
10     var body: some View {
11         PageViewController(controllers: viewControllers)
12     }
13 }
14 
15 struct PageView_Preview: PreviewProvider {
16     static var previews: some View {
17         PageView()
18     }
19 }

第5步

更新预览提供程序以传递所需的视图数组,预览开始工作。

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5 
 6     init(_ views: [Page]) {
 7         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 8     }
 9 
10     var body: some View {
11         PageViewController(controllers: viewControllers)
12     }
13 }
14 
15 struct PageView_Preview: PreviewProvider {
16     static var previews: some View {
17         PageView(features.map { FeatureCard(landmark: $0) })
18             .aspectRatio(3/2, contentMode: .fit)
19     }
20 }

第6步

在继续之前预览固定到画布上 - 此视图是所有操作的位置。PageView 

二、创建View Controller的数据源

在几个简短的步骤中,您已经做了很多 - 使用a 来从SwiftUI视图中显示内容SwiftUI。现在是时候启用滑动交互以从一个页面移动到另一个页面。PageViewControllerUIPageViewController

流程图,中心是Turtle Rock的图像。 该图像标记为UIPageViewController,并且具有指向右侧的指针,标记为View。 图像下方是一个从图像延伸出来的协调器块;  这标记为数据源。

表示UIKit视图控制器的SwiftUI视图可以定义CoordinatorSwiftUI管理类型,并将其作为可表示视图的上下文的一部分提供。

第1步

Coordinator在里面声明一个嵌套PageViewController

SwiftUI管理您的类型的协调器,并在调用上面创建的方法时将其作为上下文的一部分提供。UIViewControllerRepresentable

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeUIViewController(context: Context) -> UIPageViewController {
 8         let pageViewController = UIPageViewController(
 9             transitionStyle: .scroll,
10             navigationOrientation: .horizontal)
11 
12         return pageViewController
13     }
14 
15     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
16         pageViewController.setViewControllers(
17             [controllers[0]], direction: .forward, animated: true)
18     }
19 
20     class Coordinator: NSObject {
21         var parent: PageViewController
22 
23         init(_ pageViewController: PageViewController) {
24             self.parent = pageViewController
25         }
26     }
27 }

第2步

添加另一个方法来创建协调器。PageViewController

SwiftUI 之前调用此方法,以便在配置视图控制器时可以访问协调器对象。makeCoordinator()makeUIViewController(context:)

提示:

您可以使用此协调器实现常见的Cocoa模式,例如委托,数据源以及通过目标操作响应用户事件。

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeCoordinator() -> Coordinator {
 8         Coordinator(self)
 9     }
10 
11     func makeUIViewController(context: Context) -> UIPageViewController {
12         let pageViewController = UIPageViewController(
13             transitionStyle: .scroll,
14             navigationOrientation: .horizontal)
15 
16         return pageViewController
17     }
18 
19     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
20         pageViewController.setViewControllers(
21             [controllers[0]], direction: .forward, animated: true)
22     }
23 
24     class Coordinator: NSObject {
25         var parent: PageViewController
26 
27         init(_ pageViewController: PageViewController) {
28             self.parent = pageViewController
29         }
30     }
31 }

第3步

添加类型的一致性,并实现两个必需的方法。UIPageViewControllerDataSourceCoordinator

这两种方法建立了视图控制器之间的关系,因此您可以在它们之间来回滑动。

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeCoordinator() -> Coordinator {
 8         Coordinator(self)
 9     }
10 
11     func makeUIViewController(context: Context) -> UIPageViewController {
12         let pageViewController = UIPageViewController(
13             transitionStyle: .scroll,
14             navigationOrientation: .horizontal)
15 
16         return pageViewController
17     }
18 
19     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
20         pageViewController.setViewControllers(
21             [controllers[0]], direction: .forward, animated: true)
22     }
23 
24     class Coordinator: NSObject, UIPageViewControllerDataSource {
25         var parent: PageViewController
26 
27         init(_ pageViewController: PageViewController) {
28             self.parent = pageViewController
29         }
30 
31         func pageViewController(
32             _ pageViewController: UIPageViewController,
33             viewControllerBefore viewController: UIViewController) -> UIViewController?
34         {
35             guard let index = parent.controllers.firstIndex(of: viewController) else {
36                 return nil
37             }
38             if index == 0 {
39                 return parent.controllers.last
40             }
41             return parent.controllers[index - 1]
42         }
43 
44         func pageViewController(
45             _ pageViewController: UIPageViewController,
46             viewControllerAfter viewController: UIViewController) -> UIViewController?
47         {
48             guard let index = parent.controllers.firstIndex(of: viewController) else {
49                 return nil
50             }
51             if index + 1 == parent.controllers.count {
52                 return parent.controllers.first
53             }
54             return parent.controllers[index + 1]
55         }
56     }
57 }

第4步

添加协调器作为数据源UIPageViewController

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6 
 7     func makeCoordinator() -> Coordinator {
 8         Coordinator(self)
 9     }
10 
11     func makeUIViewController(context: Context) -> UIPageViewController {
12         let pageViewController = UIPageViewController(
13             transitionStyle: .scroll,
14             navigationOrientation: .horizontal)
15         pageViewController.dataSource = context.coordinator
16 
17         return pageViewController
18     }
19 
20     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
21         pageViewController.setViewControllers(
22             [controllers[0]], direction: .forward, animated: true)
23     }
24 
25     class Coordinator: NSObject, UIPageViewControllerDataSource {
26         var parent: PageViewController
27 
28         init(_ pageViewController: PageViewController) {
29             self.parent = pageViewController
30         }
31 
32         func pageViewController(
33             _ pageViewController: UIPageViewController,
34             viewControllerBefore viewController: UIViewController) -> UIViewController?
35         {
36             guard let index = parent.controllers.firstIndex(of: viewController) else {
37                 return nil
38             }
39             if index == 0 {
40                 return parent.controllers.last
41             }
42             return parent.controllers[index - 1]
43         }
44 
45         func pageViewController(
46             _ pageViewController: UIPageViewController,
47             viewControllerAfter viewController: UIViewController) -> UIViewController?
48         {
49             guard let index = parent.controllers.firstIndex(of: viewController) else {
50                 return nil
51             }
52             if index + 1 == parent.controllers.count {
53                 return parent.controllers.first
54             }
55             return parent.controllers[index + 1]
56         }
57     }
58 }

第5步

启用实时预览并测试滑动互动。 

三、在SwiftUI视图的状态中跟踪页面

要准备添加自定义,您需要一种从内部跟踪当前页面的方法UIPageControlPageView

为此,您将声明一个@State属性,并将绑定传递给该属性到视图。更新绑定,以匹配可见页面。PageViewPageViewControllerPageViewController

描述页面视图和UIPageViewController之间绑定如何工作的流程图。

第1步

首先添加一个绑定作为属性。currentPagePageViewController

除了声明@Binding属性之外,还要更新调用,传递绑定的值。setViewControllers(_:direction:animated:)currentPage

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6     @Binding var currentPage: Int
 7 
 8     func makeCoordinator() -> Coordinator {
 9         Coordinator(self)
10     }
11 
12     func makeUIViewController(context: Context) -> UIPageViewController {
13         let pageViewController = UIPageViewController(
14             transitionStyle: .scroll,
15             navigationOrientation: .horizontal)
16         pageViewController.dataSource = context.coordinator
17 
18         return pageViewController
19     }
20 
21     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
22         pageViewController.setViewControllers(
23             [controllers[currentPage]], direction: .forward, animated: true)
24     }
25 
26     class Coordinator: NSObject, UIPageViewControllerDataSource {
27         var parent: PageViewController
28 
29         init(_ pageViewController: PageViewController) {
30             self.parent = pageViewController
31         }
32 
33         func pageViewController(
34             _ pageViewController: UIPageViewController,
35             viewControllerBefore viewController: UIViewController) -> UIViewController?
36         {
37             guard let index = parent.controllers.firstIndex(of: viewController) else {
38                 return nil
39             }
40             if index == 0 {
41                 return parent.controllers.last
42             }
43             return parent.controllers[index - 1]
44         }
45 
46         func pageViewController(
47             _ pageViewController: UIPageViewController,
48             viewControllerAfter viewController: UIViewController) -> UIViewController?
49         {
50             guard let index = parent.controllers.firstIndex(of: viewController) else {
51                 return nil
52             }
53             if index + 1 == parent.controllers.count {
54                 return parent.controllers.first
55             }
56             return parent.controllers[index + 1]
57         }
58     }
59 }

第2步

声明@State变量,并在创建子项时将绑定传递给属性。PageViewPageViewController

重要

请记住使用$语法创建绑定到存储为状态的值。

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5     @State var currentPage = 0
 6 
 7     init(_ views: [Page]) {
 8         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 9     }
10 
11     var body: some View {
12         PageViewController(controllers: viewControllers, currentPage: $currentPage)
13     }
14 }
15 
16 struct PageView_Preview: PreviewProvider {
17     static var previews: some View {
18         PageView(features.map { FeatureCard(landmark: $0) })
19             .aspectRatio(3/2, contentMode: .fit)
20     }
21 }

第3步

通过更改其初始值来测试值是否通过绑定流向。PageViewController

实验

添加一个按钮,使页面视图控制器跳转到第二个视图。PageView

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5     @State var currentPage = 1
 6 
 7     init(_ views: [Page]) {
 8         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 9     }
10 
11     var body: some View {
12         PageViewController(controllers: viewControllers, currentPage: $currentPage)
13     }
14 }
15 
16 struct PageView_Preview: PreviewProvider {
17     static var previews: some View {
18         PageView(features.map { FeatureCard(landmark: $0) })
19             .aspectRatio(3/2, contentMode: .fit)
20     }
21 }

第4步

添加带有属性的文本视图,以便您可以关注属性的值。currentPage@State

请注意,当您从一个页面滑动到另一个页面时,该值不会更改。

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5     @State var currentPage = 0
 6 
 7     init(_ views: [Page]) {
 8         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 9     }
10 
11     var body: some View {
12         VStack {
13             PageViewController(controllers: viewControllers, currentPage: $currentPage)
14             Text("Current Page: \(currentPage)")
15         }
16     }
17 }
18 
19 struct PageView_Preview: PreviewProvider {
20     static var previews: some View {
21         PageView(features.map { FeatureCard(landmark: $0) })
22     }
23 }

第5步

在,使协调器符合,并添加方法。PageViewController.swiftUIPageViewControllerDelegatepageViewController(_:didFinishAnimating:previousViewControllers:transitionCompleted completed: Bool)

因为只要页面切换动画完成,SwiftUI就会调用此方法,您可以找到当前视图控制器的索引并更新绑定。

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6     @Binding var currentPage: Int
 7 
 8     func makeCoordinator() -> Coordinator {
 9         Coordinator(self)
10     }
11 
12     func makeUIViewController(context: Context) -> UIPageViewController {
13         let pageViewController = UIPageViewController(
14             transitionStyle: .scroll,
15             navigationOrientation: .horizontal)
16         pageViewController.dataSource = context.coordinator
17 
18         return pageViewController
19     }
20 
21     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
22         pageViewController.setViewControllers(
23             [controllers[currentPage]], direction: .forward, animated: true)
24     }
25 
26     class Coordinator: NSObject, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
27         var parent: PageViewController
28 
29         init(_ pageViewController: PageViewController) {
30             self.parent = pageViewController
31         }
32 
33         func pageViewController(
34             _ pageViewController: UIPageViewController,
35             viewControllerBefore viewController: UIViewController) -> UIViewController?
36         {
37             guard let index = parent.controllers.firstIndex(of: viewController) else {
38                 return nil
39             }
40             if index == 0 {
41                 return parent.controllers.last
42             }
43             return parent.controllers[index - 1]
44         }
45 
46         func pageViewController(
47             _ pageViewController: UIPageViewController,
48             viewControllerAfter viewController: UIViewController) -> UIViewController?
49         {
50             guard let index = parent.controllers.firstIndex(of: viewController) else {
51                 return nil
52             }
53             if index + 1 == parent.controllers.count {
54                 return parent.controllers.first
55             }
56             return parent.controllers[index + 1]
57         }
58 
59         func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
60             if completed,
61                 let visibleViewController = pageViewController.viewControllers?.first,
62                 let index = parent.controllers.firstIndex(of: visibleViewController)
63             {
64                 parent.currentPage = index
65             }
66         }
67     }
68 }

第6步

除数据源外,还将协调器指定为该委托的委托。UIPageViewController

在两个方向上连接绑定后,文本视图会在每次滑动后更新以显示正确的页码。

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageViewController: UIViewControllerRepresentable {
 5     var controllers: [UIViewController]
 6     @Binding var currentPage: Int
 7 
 8     func makeCoordinator() -> Coordinator {
 9         Coordinator(self)
10     }
11 
12     func makeUIViewController(context: Context) -> UIPageViewController {
13         let pageViewController = UIPageViewController(
14             transitionStyle: .scroll,
15             navigationOrientation: .horizontal)
16         pageViewController.dataSource = context.coordinator
17         pageViewController.delegate = context.coordinator
18 
19         return pageViewController
20     }
21 
22     func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
23         pageViewController.setViewControllers(
24             [controllers[currentPage]], direction: .forward, animated: true)
25     }
26 
27     class Coordinator: NSObject, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
28         var parent: PageViewController
29 
30         init(_ pageViewController: PageViewController) {
31             self.parent = pageViewController
32         }
33 
34         func pageViewController(
35             _ pageViewController: UIPageViewController,
36             viewControllerBefore viewController: UIViewController) -> UIViewController?
37         {
38             guard let index = parent.controllers.firstIndex(of: viewController) else {
39                 return nil
40             }
41             if index == 0 {
42                 return parent.controllers.last
43             }
44             return parent.controllers[index - 1]
45         }
46 
47         func pageViewController(
48             _ pageViewController: UIPageViewController,
49             viewControllerAfter viewController: UIViewController) -> UIViewController?
50         {
51             guard let index = parent.controllers.firstIndex(of: viewController) else {
52                 return nil
53             }
54             if index + 1 == parent.controllers.count {
55                 return parent.controllers.first
56             }
57             return parent.controllers[index + 1]
58         }
59 
60         func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
61             if completed,
62                 let visibleViewController = pageViewController.viewControllers?.first,
63                 let index = parent.controllers.firstIndex(of: visibleViewController)
64             {
65                 parent.currentPage = index
66             }
67         }
68     }
69 }

四、添加自定义页面控件

您已准备好在视图中添加自定义,包含在SwiftUI 视图中。UIPageControlUIViewRepresentable

描述UIPageViewController和UIPageControl之间绑定流程的流程图。

第1步

创建一个名为的新SwiftUI视图文件更新类型以符合协议。PageControl.swiftPageControlUIViewRepresentable

UIViewRepresentable类型具有相同的生命周期,其方法与其基础UIKit类型相对应。UIViewControllerRepresentable

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageControl: UIViewRepresentable {
 5     var numberOfPages: Int
 6     @Binding var currentPage: Int
 7 
 8     func makeUIView(context: Context) -> UIPageControl {
 9         let control = UIPageControl()
10         control.numberOfPages = numberOfPages
11 
12         return control
13     }
14 
15     func updateUIView(_ uiView: UIPageControl, context: Context) {
16         uiView.currentPage = currentPage
17     }
18 }

第2步

用页面控件替换文本框,从a切换VStackZStackfor布局。

因为您正在将页面计数和绑定传递给当前页面,所以页面控件已显示正确的值。

接下来,使页面控件具有交互性,以便用户可以点击一侧或另一侧在页面之间移动。

 

 1 import SwiftUI
 2 
 3 struct PageView<Page: View>: View {
 4     var viewControllers: [UIHostingController<Page>]
 5     @State var currentPage = 0
 6 
 7     init(_ views: [Page]) {
 8         self.viewControllers = views.map { UIHostingController(rootView: $0) }
 9     }
10 
11     var body: some View {
12         ZStack(alignment: .bottomTrailing) {
13             PageViewController(controllers: viewControllers, currentPage: $currentPage)
14             PageControl(numberOfPages: viewControllers.count, currentPage: $currentPage)
15                 .padding(.trailing)
16         }
17     }
18 }
19 
20 struct PageView_Preview: PreviewProvider {
21     static var previews: some View {
22         PageView(features.map { FeatureCard(landmark: $0) })
23     }
24 }

第3步

在其中创建嵌套Coordinator类型,并添加一个方法来创建和返回新的协调器。PageControlmakeCoordinator()

因为UIControl子类使用目标操作模式而不是委托,所以这实现了一种更新当前页面绑定的方法。UIPageControlCoordinator@objc

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageControl: UIViewRepresentable {
 5     var numberOfPages: Int
 6     @Binding var currentPage: Int
 7 
 8     func makeCoordinator() -> Coordinator {
 9         Coordinator(self)
10     }
11 
12     func makeUIView(context: Context) -> UIPageControl {
13         let control = UIPageControl()
14         control.numberOfPages = numberOfPages
15 
16         return control
17     }
18 
19     func updateUIView(_ uiView: UIPageControl, context: Context) {
20         uiView.currentPage = currentPage
21     }
22 
23     class Coordinator: NSObject {
24         var control: PageControl
25 
26         init(_ control: PageControl) {
27             self.control = control
28         }
29 
30         @objc func updateCurrentPage(sender: UIPageControl) {
31             control.currentPage = sender.currentPage
32         }
33     }
34 }

第4步

添加协调器作为事件的目标,将方法指定为要执行的操作。valueChangedupdateCurrentPage(sender:)

 

 1 import SwiftUI
 2 import UIKit
 3 
 4 struct PageControl: UIViewRepresentable {
 5     var numberOfPages: Int
 6     @Binding var currentPage: Int
 7 
 8     func makeCoordinator() -> Coordinator {
 9         Coordinator(self)
10     }
11 
12     func makeUIView(context: Context) -> UIPageControl {
13         let control = UIPageControl()
14         control.numberOfPages = numberOfPages
15         control.addTarget(
16             context.coordinator,
17             action: #selector(Coordinator.updateCurrentPage(sender:)),
18             for: .valueChanged)
19 
20         return control
21     }
22 
23     func updateUIView(_ uiView: UIPageControl, context: Context) {
24         uiView.currentPage = currentPage
25     }
26 
27     class Coordinator: NSObject {
28         var control: PageControl
29 
30         init(_ control: PageControl) {
31             self.control = control
32         }
33 
34         @objc func updateCurrentPage(sender: UIPageControl) {
35             control.currentPage = sender.currentPage
36         }
37     }
38 }

第5步

现在尝试所有不同的交互 - 显示UIKit和SwiftUI视图和控制器如何协同工作。PageView 

posted @ 2019-08-23 11:15  为敢技术  阅读(1453)  评论(0编辑  收藏  举报