Add as SwiftUI .keyboardShortcut() helper

[nighthawk]

This adds a .keyboardShortcut(_ shortcut: KeyboardShortcuts.Name) helper function to assign a shortcut defined through this KeyboardShortcuts to a SwiftUI button. This provides a similar functionality to the existing NSMenuItem extension, but when using SwiftUI's Commands to define your menu items.

This can be used as follows:

@main
struct MyApp: App {
  
  var body: some Scene {
    WindowGroup {
      ...
    }
    .commands {
      CommandMenu("Unicorns") {
        Button("Toggle Unicorn Mode") { ... }
        .keyboardShortcut(.toggleUnicornMode)
      }
    }
  }

}

In my testing on macOS 12 this works well without having to disable the global keyboard shortcut while the menu is visible, but I'm not really sure if it's safe to do so.

[sindresorhus]

If the shortcut attached to KeyboardShortcuts.Name is changed by the user, it will not be changed here. You need to use a ViewModifier and listen to updates to the keyboard shortcut, like the NSMenuItem extension does.

[nighthawk]

I expected so, too, but that's not necessary in my testing. As soon as I assign a new keyboard shortcut using the Recorder, the .commands is re-evaluated as this method will be called again.

I'm not sure how that works though, but empirically it works.

[sindresorhus]

I think that only applies if they're in the same view. But that's not the case if they are in different windows (preferences vs main app window).

[sindresorhus]

@nighthawk Still interested in working or this or should I close?

[nighthawk]

Excuse the slow reply. I didn't yet have time to look into how to do it using a ViewModifier and haven't yet had any urgency for it as it works as is for how I use it even though I use it across different views, i.e., the app's settings view (to set it) and the app's main window's menu item (to display and trigger it).

[sindresorhus]

Closing for lack of activity. #101