On Aug 1, 2009, at 07:03, Richard Somers wrote:
It is an inspector panel. One panel for many documents.
This is a crucial piece of information which changes the nature of the problem to be solved. You gotta tell us the relevant information up front. :)
If I create the inspector panel in the document nib and bind the array controller to the File's Owner everything works great. It is when I try to create an inspector panel in a separate nib that something goes wrong. The error message "Cannot perform operation without a managed object context" indicates the binding is not working. I think this is my problem.
Er, no. You want one inspector for all documents, so loading a new panel for each document is simply not the answer.
On Aug 1, 2009, at 09:32, Richard Somers wrote:
Upon further investigation I have discovered that my window controller -document method returns nil. So as far as the binding is concerned I have no document and no managed object context. I thought the -document method would automatically return a pointer to my persistent document but that is not the case.
Yes, that's what I said earlier. Excuse me for being facetious, but when you say "automatically" you mean "magically", and there's no magic here. The "document" property of a window controller gets set to a non-nil value *because and only because* the window controller is added to the list of the document's window controllers. (See [NSDocument addWindowController:].) Otherwise, the window controller is freestanding, and if it wants some document's object pointer (or the document's managed object context pointer) it has to use a different strategy.
So how do I get my NSWindowController subclass -document method to return a pointer to my persistent document?
In your scenario, you don't. Your panel needs to switch from document to document over time, so forget about [self document] in its window controller.
What you want is for the inspector to reflect the state of the *frontmost* document window -- that is, the current "main" window. So, one strategy is to override 'windowDidBecomeMain:' and/or 'windowDidResignMain:' in your document window controller, and have the document window controller message the panel's window controller directly (which is a singleton and therefore can be referenced via a static variable, or via an instance variable of the app delegate). Another strategy is for the panel window controller to register itself as an observer of *all* NSWindowDidBecomeMain and NSWindowDidResignMain notifications, and to switch itself based on the notifying window. (You can get the window out of the NSNotification object, and use '[[[window windowController] document] isKindOfClass: [MyDocument class]]' to find out whether the window is one of your document windows.)
HTH _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
