One App Delegate, Two Windows
===

I have a simple Cocoa app. It has two windows, each in a separate xib file:

 - MainMenu.xib
 - SecondaryWindow.xib

I have an AppDelegate class, which has a reference to the window in MainMenu.xib. I'm trying to make it have a reference to the window in SecondaryWindow.xib. I'm confused about how to do this. I have made an outlet, as such:

    @interface AppDelegate : NSObject <NSApplicationDelegate>
    
    @property (assign) IBOutlet NSWindow *window;
    @property (assign) IBOutlet NSWindow *secondaryWindow;
    
    @end

Here's the implementation:

    @implementation AppDelegate
    
    @synthesize window = _window;
    @synthesize secondaryWindow = _secondaryWindow;
    
    
    - (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
        NSLog(@"_window = %@", _window);
        NSLog(@"_secondaryWindow = %@", _secondaryWindow);
    }
    
    @end

_secondaryWindow is always (null)

I've add an outlet from in SecondaryWindow.xib connection the second window to the outlet in AppDelegate. What else do I need to do in SecondaryWindow.xib to make the connection complete?
