我是一个SwiftUI新手，正在努力将SwiftUI功能添加到我现有的UIKit/Storyboard代码中。我想从SwiftUI按钮调用UIKit函数。非常感谢您的帮助。以下是为本次讨论而简化的相关代码。从下面的代码中，我想从SwiftUI中的If语句中调用函数startAction((和stopAction((。。。
if (startStop_flag) {
//******** call StartAction()
} else {
//******* call StopAction()
}
下面的整个代码。一些上下文：当应用程序运行时，屏幕的下半部分将显示"UIkit情节提要视图"；并显示按钮"；打开Swift Container View"；。当用户单击此按钮时，将打开SwiftUI容器视图。该视图将显示"；这是一个swiftUI视图"；并显示一个按钮"；启动/停止"；。当用户单击此按钮时，需要调用StartAction((或StopAction((。这两个函数位于UIViewController中。我希望我清楚这个问题和要求。
ViewController.swift
class ViewController: UIViewController {
@IBOutlet weak var nativeView: UIView!
@IBOutlet weak var nativeView_Label: UILabel!
@IBOutlet weak var nativeView_openSwiftViewBtn: UIButton!
@IBOutlet weak var containerView_forSwiftUI: UIView!
@IBSegueAction func embedSwiftUIView(_ coder: NSCoder) -> UIViewController? {
return UIHostingController(coder: coder, rootView: SwiftUIView2(text: "Container View"))
}
var toggleOpenCloseContainerView : Bool = false
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
containerView_forSwiftUI.isHidden = true
}
@IBAction func openContainerView_touchInside(_ sender: Any) {
if (toggleOpenCloseContainerView) {
containerView_forSwiftUI.isHidden = false
toggleOpenCloseContainerView = false
nativeView_openSwiftViewBtn.setTitle("Close Swift Container View", for: .normal)
} else {
containerView_forSwiftUI.isHidden = true
toggleOpenCloseContainerView = true
nativeView_openSwiftViewBtn.setTitle("Open Swift Container View", for: .normal)
}
}
// These two functions need to be called from the SwiftUI's button.
func startAction() {
print("Start Action called from SwiftUI's button")
}
func stopAction() {
print("Stop Action called from SwiftUI's button")
}
}
swiftUI功能在此文件中
struct SwiftUIView2: View {
var text: String
@State var startStop_flag: Bool = true
var body: some View {
VStack {
Text(text)
HStack {
Image(systemName: "smiley")
Text("This is a SwiftUI View")
Spacer()
Button("(startStop_flag ? "Start": "Stop")") {
startStop_flag = !startStop_flag
if (startStop_flag) {
//******** call StartAction()
} else {
//******* call StopAction()
}
} .padding()
.background(Color.red)
.cornerRadius(40)
.foregroundColor(.white)
.padding(5)
.overlay(
RoundedRectangle(cornerRadius: 40)
.stroke(Color.red, lineWidth: 1)
)
}
}
.font(.largeTitle)
.background(Color.blue)
}
}
struct SwiftUIView_Previews: PreviewProvider {
static var previews: some View {
SwiftUIView2(text: "Sample Text")
}
}
您可以为此使用闭包。首先，在SwiftUI视图中定义并调用它们。
struct SwiftUIView2: View {
var text: String
var startAction: (() -> Void) /// define closure 1
var stopAction: (() -> Void) /// define closure 2
...
...
Button("(startStop_flag ? "Start": "Stop")") {
startStop_flag = !startStop_flag
if (startStop_flag) {
//******** call StartAction()
startAction()
} else {
//******* call StopAction()
stopAction()
}
}
}
然后，只需在ViewController.swift中分配闭包的内容。
@IBSegueAction func embedSwiftUIView(_ coder: NSCoder) -> UIViewController? {
return UIHostingController(
coder: coder,
rootView: SwiftUIView2(
text: "Container View",
startAction: { [weak self] in
self?.startAction()
},
stopAction: { [weak self] in
self?.stopAction()
}
)
)
}
这里是从SwiftUI按钮按下打开UIkit ViewController的最简单方法。
Button("Next Page") {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let rootViewController = storyboard.instantiateViewController(withIdentifier: "ProfileVC")
if let window = UIApplication.shared.windows.first {
window.rootViewController!.present(rootViewController, animated: true)
}
}
}