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objective-ccocoanspanel

How to avoid deallocating a NSPanel when closed by the user

I am developing a small and simple status menu application.
There is a menu and when the user clicks on it, a HUD window (NSPanel) should appear. This is how I show the panel: 

[hudWindow makeKeyAndOrderFront: self];

This is how I dismiss the window: 

[hudWindow orderOut: nil];

So that's the events chain:

  1. When the app starts I dismiss the window;
  2. Then the user (that's me :-)) clicks on the menu item and makes the panel appear;
  3. Then I click on the x and close the panel;
  4. Then I click again on the menu item and the window doesn't appear again.

It doesn't appear again probably because it gets deallocated, and I have put a weak storage, otherwise with __unsafe_unretained it would crash at the second launch.
So I'm guessing if there's a way to avoid deallocating the window when the user clicks on it.
I have tried with a strong storage but this case at the second launch I'm unable to close it again and that's a problem.
There are many menu status applications that are able to display a window without that the user can "kill" it, I would make something of similar.

Solution

  • You should uncheck the "Release When Closed" checkbox in IB (or done the equivalent in code). That box is checked by default for panels.

    Using a strong pointer probably doesn't work because the releasedWhenClosed setting overrides that. Having a strong pointer just means that the retain count will be at least one, but that doesn't prevent the system from explicitly sending a release message to the panel.