Instance method 'applicationDidFinishLaunching' nearly matches optional

Question

Created Dec ’20

Replies 6

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This is a swift project that has C bridged. As soon as the C was bridged I got the warning: Instance method 'applicationDidFinishLaunching' nearly matches optional requirement 'applicationDidFinishLaunching' of protocol 'NSApplicationDelegate'

When launched, the func applicationDidFinishLaunching is not called.

This is for MacOS 10.15. Using Xcode 12.3.

Boost

Answer 1

OOPer OP

Dec ’20

Please show your code where your applicationDidFinishLaunching exists. Something is wrong there.

0

Answer 2

Claude31 OP

Jan ’21

The func signature is:

Code Block     func applicationDidFinishLaunching(_ aNotification: Notification) { }

May be you forgot the underscore ?
If you remove the _, func which is optional, will never be called.

0

Answer 3

bluelamar OP

Jan ’21

Here is the code copy and pasted as is: p.s. it is linked with Boost lib (C++)

Code Block @main
class AppDelegate: NSObject, NSApplicationDelegate, UNUserNotificationCenterDelegate {
    var window: NSWindow!
// Xcode warning here: Instance method 'applicationDidFinishLaunching' nearly matches optional requirement 'applicationDidFinishLaunching' of protocol 'NSApplicationDelegate'
//
    func applicationDidFinishLaunching(_ aNotification: Notification) {
        // Create the SwiftUI view that provides the window contents.
        print("FIX applicationDidFinishLaunching")
        let contentView = ContentView()
        // Create the window and set the content view.
        window = NSWindow(
            contentRect: NSRect(x: 0, y: 0, width: 480, height: 300),
            styleMask: [.titled, .closable, .miniaturizable, .resizable, .fullSizeContentView],
            backing: .buffered, defer: false)
        window.isReleasedWhenClosed = false
        window.center()
        window.setFrameAutosaveName("Main Window")
        window.contentView = NSHostingView(rootView: contentView)
        window.makeKeyAndOrderFront(nil)
    }
// Xcode warning here: Instance method 'applicationWillTerminate' nearly matches optional requirement 'applicationDidFinishLaunching' of protocol 'NSApplicationDelegate'
//
    func applicationWillTerminate(_ aNotification: Notification) {
        // Insert code here to tear down your application
    }
}

0

Answer 4

Claude31 OP

Jan ’21

Signature seems OK.

Could you post the complete class AppDelegate file ?

Did you try an option-clean build folder ?

0

Answer 5

OOPer OP

Jan ’21

Accepted Answer

Here is the code copy and pasted as is: p.s. it is linked with Boost lib (C++)

Thanks for showing your code. Your method header is seemingly right.

Can you try changing the method header as follows and tell us what happens?

Code Block     func applicationDidFinishLaunching(_ aNotification: AppKit.Notification) { //<- Use `AppKit.Notification` instead of `Notification`

3

Answer 6

bluelamar OP

Jan ’21

Problem resolved. My error was I defined a "struct Notification" in the project which conflicts with Foundation "struct Notification". Thus the signature of the functions applicationDidFinishLaunching and applicationWillTerminate would not match!

3