Why fatal error with call awakeFromNib?

Question

wlionel OP

Created Mar ’20

Replies 7

Boosts 0

Views 1.3k

Participants 2

Hello:

I have this code and getting error:

Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value

What can I do to prevent the error? Here is the code:

class ViewController: NSViewController,NSWindowDelegate {
var window: NSWindow!
    override func viewDidLoad() {
        super.viewDidLoad()
    }
  func windowShouldClose(sender: AnyObject) -> Bool {
      NSApp.hide(nil)
      return false
  }
    override func awakeFromNib() {
        super.awakeFromNib()
        view.window!.delegate! = self //Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value
    }

Thanks for help.

Answered by Claude31 in 412309022

Did you get the clarification from Apple reviewer on the exact need ?

I understood it as a way to reopen the window once closed.

The way I would do this with a storyboard (it is really a sketch, need to be tested, probably need to keep a reference of the initial windowController when appDidfinishlaunching to avoid creating multiple instances…)

create a menuItem in File or Window menu: such as 'Reopen window'

in AppDelegate

create an IBAction to open the window

    @IBAction func reopenFirstWindow(_ sender: NSMenuItem) {
        print("Reopen me")
        let storyboard = NSStoryboard(name: "Main", bundle: nil)
        if let wc = storyboard.instantiateController(withIdentifier: "FirstWC") as? FirstWindowController {
            wc.window!.makeKeyAndOrderFront(wc.window!)
        }
    }

Connect the menuItem to the IBAction by control-drag from the menuItem to the FirstResponder (yellow) square over the mainmenubar in IB.

select the IBAction reopenFirstWindow

Give FirstWC as identifier for the windowController

Boost

Answer 1

Claude31 OP

Mar ’20

Where is window set ?

If you test you will see view.window is nil

It is defined as implicit unwrapped, but initial value is nil as long as you have not set it.

Do you use a storyboard ?

Then you should get a windowController and its ViewController, of type ViewController.

If so, why do you need awake ? Why setting the delegate ?

Or did you create a nib for the window ?

0

Answer 2

wlionel OP

Mar ’20

Hello Claude:

I do have a storyboard. I am still trying to resolve the issue of restoring a window after it has been closed. The effort here is to hide the window when the user clicks close so that the window can be restored.

Frankly I am now at my wits end!

0

Answer 3

Claude31 OP

Mar ’20

Accepted Answer

Did you get the clarification from Apple reviewer on the exact need ?

I understood it as a way to reopen the window once closed.

The way I would do this with a storyboard (it is really a sketch, need to be tested, probably need to keep a reference of the initial windowController when appDidfinishlaunching to avoid creating multiple instances…)

create a menuItem in File or Window menu: such as 'Reopen window'

in AppDelegate

create an IBAction to open the window

    @IBAction func reopenFirstWindow(_ sender: NSMenuItem) {
        print("Reopen me")
        let storyboard = NSStoryboard(name: "Main", bundle: nil)
        if let wc = storyboard.instantiateController(withIdentifier: "FirstWC") as? FirstWindowController {
            wc.window!.makeKeyAndOrderFront(wc.window!)
        }
    }

Connect the menuItem to the IBAction by control-drag from the menuItem to the FirstResponder (yellow) square over the mainmenubar in IB.

select the IBAction reopenFirstWindow

Give FirstWC as identifier for the windowController

0

Answer 4

wlionel OP

Mar ’20

Hello Claude:

I found a way to open the window after it was closed (with the red x button) using a modal storyboard segue from the menu link. To quit after it was hooked up this way I had to use an @IBOutlet as follows:

@IBActionfunc closeApplication(_ sender: NSMenuItem) {
       
        NSApplication.shared.terminate(AppDelegate.closeApplication)
        print("Stop the App")
    
    }

Without that it wouldn't close.

Thanks for your great help during this difficult journey. That was the last hurdle to jump over.

0

Answer 5

Claude31 OP

Mar ’20

Wish you the best now with the review board.

0

Answer 6

wlionel OP

Mar ’20

Hello:

As I was reviewing everything before submission I ran into an inexplicable problem:

When I Close the Main Window by clicking the red x and reopen it, then I load another window from a link on the main window and try to load another window, The Main window becomes unusable. I have to close it then reopen it to click on the links. Then when I open another window, the previous window I opened becomes unusable until I close the Main Window.

To have access to more that one window at a time I have to close the Main Window.

Have you seen anythink like this?

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Answer 7

wlionel OP

Mar ’20

After some experimenting,

I found that making the segues "show" instead of "modal" I can open all the windows initially and still access the Main Window.

However, When I close the Main Window with the close red x, and reopen it, I can launch all the windows but after launching them I have to close it to use the windows.

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