I’ve got some problem with programmatically creating a window showing a NSOutlineView object.

For some reason I do not want to use Interface Builder to create that window and view. Somehow I manage to bring the window including the outline view on screen. For that I need to use alloc-method several times. Going on in the program I want to hide only the NSOutlineView object (with NSScrollView and NSClipView) and freeing the memory. The window should stay alive. I tried to use release at appropriate times. But, PROBLEM: when I release one of the views after its retainCount is down to 1, so it should be deallocated now, my application is crashing. Error message: myApplication has exited due to signal 11 (SIGSEGV)

Can anyone please explain to me, how I can create the needed NSOutlineView and deallocate it the right way?

Strange observation: the crashing occours only when I use setDocumentView- or setContentView-method.

here is my test code that does not work:

---

MyOutlineView.h:

#import <Cocoa/Cocoa.h> @interface MyOutlineView : NSObject { NSWindow *window; NSScrollView *scrollView; }

• (IBAction)clear:(id)sender; @end

---

MyOutlineView.m:

#import “MyOutlineView.h” @implementation MyOutlineView

• (void)applicationDidFinishLaunching:(NSNotification )aNotification { / preparing some frame for window’s contentView and all other views (unimportant now) / NSRect contentRect; contentRect.size.width = 270.; contentRect.size.height = 180.; contentRect.origin.x = 0.; contentRect.origin.y = 0.; / any style for window (unimportant now) / unsigned int styleMask = NSTitledWindowMask | NSClosableWindowMask; / allocating and initializing NSOutlineView, NSClipView and NSScrollView / NSOutlineView *outlineView = [[NSOutlineView alloc] initWithFrame:contentRect]; NSClipView *clipView = [[NSClipView alloc] initWithFrame:contentRect]; scrollView = [[NSScrollView alloc] initWithFrame:contentRect]; / setting outlineView as documentView of clipView and clipView as contentView of scrollView / [clipView setDocumentView:outlineView]; [scrollView setContentView:clipView]; / allocating and initializing NSWindow / window = [[NSWindow alloc] initWithContentRect:contentRect styleMask:styleMask backing:NSBackingStoreBuffered defer:NO]; / setting scrollView as window’s contentView / window contentView] addSubview:scrollView]; / showing window */ [window makeKeyAndOrderFront:self]; }

• ([[IBAction)clear:(id)sender { /* cut connection between scrollView and window / [scrollView removeFromSuperview]; NSLog(@”[scrollView retainCount] %d”, [scrollView retainCount]); [scrollView release]; //scrollView got second retain from NSView’s addSubview-method / if you close the window before pressing command-o scrollView will be released by that ones. So at this point only one release would be enought. */ NSLog(@”[scrollView retainCount] %d”, [scrollView retainCount]); [scrollView release];//scrollView got first retain from alloc scrollView = nil; NSLog(@”[scrollView retainCount] %d”, [scrollView retainCount]); } @end