我正在学习 SwiftUI,目前我的重点是实现一种我能够使用 UIKit 实现的方法。我需要创建一个方法,该方法根据布尔值确定是应该推送视图还是以模态方式呈现视图。
在 UIKit 中,我的代码是:
var presentVC = true // boolean that determines whether VC will be presented or pushed
let vc = ViewController() //Your VC that will be pushed or presented
if (presentVC == true) {
self.presentViewController(vc, animated: true, completion: nil)
} else {
self.navigationController.pushViewController(vc, animated: true)
}
但在 SwiftUI 中,我不确定如何使用以下内容正确实现:
NavigationLink 和 .sheet 修饰符似乎与视图实现结合在一起。 有没有人已经在 SwiftUI 中遇到并解决了这种情况?谢谢
我使用 SwiftUI 1.0,因为我需要支持 iOS 13。
答案 0 :(得分:1)
一个可能的解决方案是创建一个具有可用演示类型的自定义枚举:
enum PresentationType {
case push, sheet // ...
}
并创建用于激活不同视图的自定义绑定:
func showChildView(presentationType: PresentationType) -> Binding<Bool> {
.init(
get: { self.showChildView && self.presentationType == presentationType },
set: { self.showChildView = $0 }
)
}
完整代码:
struct ContentView: View {
@State var presentationType = PresentationType.push
@State var showChildView = false
func showChildView(as presentationType: PresentationType) -> Binding<Bool> {
.init(
get: { self.showChildView && self.presentationType == presentationType },
set: { self.showChildView = $0 }
)
}
var body: some View {
NavigationView {
VStack {
Button(action: {
self.presentationType = .push
self.showChildView = true
}) {
Text("Present new view as Push")
}
Button(action: {
self.presentationType = .sheet
self.showChildView = true
}) {
Text("Present new view as Sheet")
}
}
.navigationBarTitle("Main view", displayMode: .inline)
.background(
NavigationLink(
destination: ChildView(),
isActive: self.showChildView(presentationType: .push),
label: {}
)
)
}
.sheet(isPresented: self.showChildView(presentationType: .sheet)) {
ChildView()
}
}
}
struct ChildView: View {
var body: some View {
ZStack {
Color.red
Text("Child view")
}
}
}