在 MacOS SwiftUI 应用程序中列出和关闭 Windows

Question

我有这个小示例应用程序，它创建了多个 Windows 我的 SwiftUI MacOS 应用程序。
是否可以：

要在 MainView 中列出所有打开的 windows？
要从 MainView 关闭单个 window？
要从 MainView 向单个 window 发送消息？

@main
struct MultiWindowApp: App {
  @State var gvm = GlobalViewModel()
  var body: some Scene {
    WindowGroup {
      MainView()
      .environmentObject(gvm)
    }
    WindowGroup("Secondary") {
      SecondaryView(bgColor: .blue)
      .environmentObject(gvm)
    }
    .handlesExternalEvents(matching: Set(arrayLiteral: "*"))
  }
}


struct MainView: View {
  @Environment(\.openURL) var openURL
  @EnvironmentObject var vm : GlobalViewModel

  var body: some View {
    VStack {
      Text("MainView")
      Button("Open Secondary") {
        if let url = URL(string: "OpenNewWindowApp://bla") {
          openURL(url)
        }
       //List of all open Windows
          // Button to close a single window
          // Button to set color of  a single window to red
      }
    }
    .padding()
  }
}

struct SecondaryView: View {
  var bgColor : Color

  @EnvironmentObject var vm : GlobalViewModel

  var body: some View {
    VStack{
      Spacer()
      Text("Viewer")
      Text("ViewModel: \(vm.name)")
      Button("Set VM"){
        vm.name = "Tom"
      }
      Spacer()
    }
    .background(bgColor)
    .frame(minWidth: 300, minHeight: 300, idealHeight: 400, maxHeight: .infinity, alignment: .center )
  }
}

class GlobalViewModel :ObservableObject {
  @Published var name = "Frank"
}

Answer 1

可能有更以 SwiftUI 为中心的方法来执行此操作。如果还没有，我当然希望 Apple 为 Mac 方面添加一些更好的 window 管理内容——现在，一切似乎都有点乱七八糟。

这是我想出的：


@main
struct MultiWindowApp: App {
  @State var gvm = GlobalViewModel()
  var body: some Scene {
    WindowGroup {
      MainView()
      .environmentObject(gvm)
    }
    WindowGroup("Secondary") {
      SecondaryView(bgColor: .blue)
      .environmentObject(gvm)
    }
    .handlesExternalEvents(matching: Set(arrayLiteral: "*"))
  }
}


struct MainView: View {
  @Environment(\.openURL) var openURL
  @EnvironmentObject var vm : GlobalViewModel

  var body: some View {
    VStack {
      Text("MainView")
        List {
            ForEach(Array(vm.windows), id: \.windowNumber) { window in
                HStack {
                    Text("Window: \(window.windowNumber)")
                    Button("Red") {
                        vm.setColor(.red, forWindowNumber: window.windowNumber)
                    }
                    Button("Close") {
                        window.close()
                    }
                }
                
            }
        }
      Button("Open Secondary") {
        if let url = URL(string: "OpenNewWindowApp://bla") {
          openURL(url)
        }
      }
    }
    .padding()
    .frame(maxWidth: .infinity, maxHeight: .infinity)
  }
}

struct SecondaryView: View {
  var bgColor : Color
  @EnvironmentObject var vm : GlobalViewModel

    @State private var windowNumber = -1
    
  var body: some View {
    VStack{
        HostingWindowFinder { window in
            if let window = window {
                vm.addWindow(window: window)
                self.windowNumber = window.windowNumber
            }
        }
      Spacer()
      Text("Viewer")
      Text("ViewModel: \(vm.name)")
      Button("Set VM"){
        vm.name = "Tom"
      }
      Spacer()
    }
    .background(vm.backgroundColors[windowNumber] ?? bgColor)
    .frame(minWidth: 300, minHeight: 300, idealHeight: 400, maxHeight: .infinity, alignment: .center )
  }
}

class GlobalViewModel : NSObject, ObservableObject {
    @Published var name = "Frank"
    @Published var windows = Set<NSWindow>()
    @Published var backgroundColors : [Int:Color] = [:]
    
    func addWindow(window: NSWindow) {
        window.delegate = self
        windows.insert(window)
    }
    
    func setColor(_ color: Color, forWindowNumber windowNumber: Int) {
        backgroundColors[windowNumber] = color
    }
}

extension GlobalViewModel : NSWindowDelegate {
    func windowWillClose(_ notification: Notification) {
        if let window = notification.object as? NSWindow {
            windows = windows.filter { [=10=].windowNumber != window.windowNumber }
        }
    }
}

struct HostingWindowFinder: NSViewRepresentable {
    var callback: (NSWindow?) -> ()

    func makeNSView(context: Self.Context) -> NSView {
        let view = NSView()
        DispatchQueue.main.async { [weak view] in
            self.callback(view?.window)
        }
        return view
    }
    func updateNSView(_ nsView: NSView, context: Context) {}
}

我正在使用 https://lostmoa.com/blog/ReadingTheCurrentWindowInANewSwiftUILifecycleApp/ 中的技巧来获取对 NSWindow 的引用。它被存储在一组视图模型中。稍后，要访问关闭 windows 等内容。我通过 windowNumber.

引用 windows

当 window 出现时，它会将自己添加到视图模型的 window 列表中。然后，当视图模型作为委托获得 windowWillClose 调用时，它会将其从列表中删除。

背景颜色的设置是通过视图模型上的 backgroundColors 属性完成的。如果没有一组，它使用传入的背景颜色属性。您可以选择多种不同的方式来构建这一点。

在 MacOS SwiftUI 应用程序中列出和关闭 Windows

Listing and closing Windows in a MacOS SwiftUI App

macos

swiftui

swiftui-windowgroup