Show NSWindow from separate nib (not modal) - objective-c

Question

How to do it? I simply want to load a window and show it in front of the main window.
NSWindowController* controller = [[NSWindowController alloc] initWithWindowNibName: #"MyWindow"];
NSWindow* myWindow = [controller window];
[myWindow makeKeyAndOrderFront: nil];
This code shows the window for one moment and then hides it. IMHO this is because I don't keep reference to the window (I use ARC). [NSApp runModalForWindow: myWindow]; works perfectly but I don't need to show it modally.

Answer 1

Yes, with ARC if you don't hold a reference to the window it will be torn down as soon you as you exit the routine you were in. You need to hold a strong reference to it in an ivar. [NSApp runModalForWindow: myWindow] is different because the NSApplication object holds a reference to the window as long as it is being run modally.

Answer 2

You should likely do something similar to the following, which creates a strong reference to the NSWindowController instance you create:
.h:
#class MDWindowController;
#interface MDAppDelegate : NSObject <NSApplicationDelegate> {
__weak IBOutlet NSWindow *window;
MDWindowController *windowController;
}
#property (weak) IBOutlet NSWindow *window;
#property (strong) MDWindowController *windowController;
- (IBAction)showSecondWindow:(id)sender;
#end
.m:
#import "MDAppDelegate.h"
#import "MDWindowController.h"
#implementation MDAppDelegate
#synthesize window;
#synthesize windowController;
- (IBAction)showSecondWindow:(id)sender {
if (windowController == nil) windowController =
[[MDWindowController alloc] init];
[windowController showWindow:nil];
}
#end
Note that rather than sending the makeKeyAndOrderFront: method directly to the NSWindowController's NSWindow, you can just use NSWindowController's built-in showWindow: method.
While the above code (and sample project below) use a custom subclass of NSWindowController, you also use a generic NSWindowController and create the instance using initWithWindowNibName: (just make sure the File's Owner of the nib file is set to NSWindowController rather than a custom subclass like MDWindowController).
Sample project:
http://www.markdouma.com/developer/MDWindowController.zip